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J Am Coll Cardiol 48: 2340-2347
Carlo Pappone, MD, PhD, FACC, Giuseppe
Augello, MD, Simone Sala, MD, Filippo Gugliotta, BEng, Gabriele Vicedomini, MD,
Simone Gulletta, MD, Gabriele Paglino, MD, Patrizio Mazzone, MD, Nicoleta Sora,
MD, Isabelle Greiss, MD, Andreina Santagostino, MD, Laura LiVolsi, MD, Nicola
Pappone, MD , Andrea Radinovic, MD, Francesco Manguso, MD, PhD and Vincenzo
Santinelli, MD
OBJECTIVES: We compared
ablation strategy with antiarrhythmic drug therapy (ADT) in patients with
paroxysmal atrial fibrillation (PAF).
BACKGROUND: Atrial fibrillation (AF) ablation strategy is superior to ADT in
patients with an initial history of PAF, but its role in patients with a long
history of AF as compared with ADT remains a challenge.
METHODS: One hundred ninety-eight patients (age, 56 ± 10 years) with PAF of 6 ±
5 years’ duration (mean AF episodes 3.4/month) who had failed ADT were
randomized to AF ablation by circumferential pulmonary vein ablation (CPVA) or
to the maximum tolerable doses of another ADT, which included flecainide,
sotalol, and amiodarone. Crossover to CPVA was allowed after 3 months of ADT.
RESULTS: By Kaplan-Meier analysis, 86% of patients in the CPVA group and 22% of
those in the ADT group who did not require a second ADT were free from recurrent
atrial tachyarrhythmias (AT) (p < 0.001); a repeat ablation was performed in 9%
of patients in the CPVA group for recurrent AF (6%) or atrial tachycardia (3%).
At 1 year, 93% and 35% of the CPVA and ADT groups, respectively, were AT-free.
Ejection fraction, hypertension, and age independently predicted AF recurrences
in the ADT group. Circumferential pulmonary vein ablation was associated with
fewer cardiovascular hospitalizations (p < 0.01). One transient ischemic attack
and 1 pericardial effusion occurred in the CPVA group; side effects of ADT were
observed in 23 patients.
CONCLUSIONS: Circumferential pulmonary vein ablation is more successful than ADT
for prevention of PAF with few complications. Atrial fibrillation ablation
warrants consideration in selected patients in whom ADT had already failed and
maintenance of sinus rhythm is desired.
J Am Coll Cardiol 48: 2243-2250
Gabe B. Bleeker, MD, Eduard R. Holman, MD,
PhD, Paul Steendijk, PhD, Eric Boersma, PhD , Ernst E. van der Wall, MD, PhD,
Martin J. Schalij, MD, PhD and Jeroen J. Bax, MD, PhD
OBJECTIVES: The purpose of
this study was to evaluate the effects of cardiac resynchronization therapy
(CRT) in heart failure patients with narrow QRS complex (<120 ms) and evidence
of left ventricular (LV) dyssynchrony on tissue Doppler imaging (TDI).
BACKGROUND: Cardiac resynchronization therapy is beneficial in selected heart
failure patients with wide QRS complex ( 120 ms). Patients with narrow QRS
complex are currently not eligible for CRT, and the potential effects of CRT are
not well studied.
METHODS: Thirty-three consecutive patients with narrow QRS complex and 33
consecutive patients with wide QRS complex (control group) were prospectively
included. All patients needed to have LV dyssynchrony 65 ms on TDI, New York
Heart Association (NYHA) functional class III/IV heart failure, and LV ejection
fraction 35%.
RESULTS: Baseline characteristics, particularly LV dyssynchrony, were comparable
between patients with narrow and wide QRS complex (110 ± 8 ms vs. 175 ± 22 ms; p
= NS). No significant relationship was observed between baseline QRS duration
and LV dyssynchrony (r = 0.21; p = NS). The improvement in clinical symptoms and
LV reverse remodeling was comparable between patients with narrow and wide QRS
complex (mean NYHA functional class reduction 0.9 ± 0.6 vs. 1.1 ± 0.6 [p = NS]
and mean LV end-systolic volume reduction 39 ± 34 ml vs. 44 ± 46 ml [p = NS]).
CONCLUSIONS: Cardiac resynchronization therapy appears to be beneficial in
patients with narrow QRS complex and severe LV dyssynchrony on TDI, with similar
improvement in symptoms and comparable LV reverse remodeling to patients with
wide QRS complex. The current results need confirmation in larger patient
cohorts.
J Am Coll Cardiol 48: 2209-2214
Joost P. van Melle, MD, PhD, Daniëlle E.P.
Verbeek, MD, Maarten P. van den Berg, MD, PhD, Johan Ormel, PhD , Marcel R. van
der Linde, MD and Peter de Jonge, PhD
OBJECTIVES: The purpose of
this research was to explore the prospective relationship between the use of
beta-blockers and depression in myocardial infarction (MI) patients.
BACKGROUND: Beta-blocker use has been reported to be associated with the
development of depression, but the methodological quality of studies in this
field is weak.
METHODS: In a multicenter study, MI patients (n = 127 non–beta-blocker users and
n = 254 beta-blocker users) were assessed for depressive symptoms (using the
Beck Depression Inventory [BDI] at baseline and t = 3, 6, and 12 months post-MI)
and International Classification of Diseases-10 depressive disorder (Composite
International Diagnostic Interview). Patients were matched using the frequency
matching procedure according to age, gender, hospital of admission, presence of
baseline depressive symptoms, and left ventricular function.
RESULTS: No significant differences were found between non–beta-blocker users
and beta-blocker users on the presence of depressive symptoms (p > 0.10 at any
of the time points) or depressive disorder (p = 0.86). Controlling for
confounders did not alter these findings. A trend toward increasing BDI scores
was seen in patients with long-term use of beta-blockers and patients with
higher beta-blocker dose.
CONCLUSIONS: In post-MI patients,
prescription of beta-blockers is not associated with an increase in depressive
symptoms or depressive disorders in the first year after MI. However,
long-term and high-dosage effects cannot be ruled out.
Europace 2006 8(12):1022-1026
Dhiraj Gupta, Rasha K. Al-Lamee, Mark J.
Earley, Peter Kistler, Stuart J. Harris, Anthony W. Nathan, Simon C. Sporton and
Richard J. Schilling
Aims The efficacy of
transvenous Cryoablation (Cryo), for the treatment of atrioventricular nodal
re-entry tachycardia (AVNRT), when compared with radiofrequency (RF) ablation,
requires further investigation.
Methods and results We sought to compare the acute- and follow-up results of 71
cases each of Cryo and RF for AVNRT using a retrospective matched case–control
study design and aimed at identifying patient and procedural factors that may
predict success with each strategy. Primary failure of Cryo (thus necessitating
RF at the same sitting) was seen in 11 (15.4%) cases, whereas there were two
(2.8%) primary failures with RF (P<0.01). Patients in the Cryo group had
significantly higher arrhythmia recurrence [14 (19.8%)] when compared with the
RF group [4 (5.6%)] (P<0.01). The incidence of recurrence following Cryo was
significantly higher if an echo beat was still inducible after ablation than if
complete slow pathway block was achieved (7/19, vs. 4/46, P<0.001). The median
number of Cryo lesions was significantly lower in patients who had recurrence
compared with those who did not (1.5 vs. 3.0, P=0.02).
Conclusion We have observed a much
higher primary failure and recurrence rate with Cryo when compared with RF for
AVNRT. It may be possible to decrease this high recurrence rate by aiming
to achieve complete slow pathway block and by increasing the number of Cryo
lesions.
PACE 2006; 29:1234–1239
MEHDI RAZAVI, M.D., JIE CHENG, M.D.,
PH.D., ABDI RASEKH, M.D., DONGHUI YANG, M.D., PH.D., SCOTT DELAPASSE, M.D.,
TOMOHIKO AI, M.D., PH.D., THOMAS MEADE, M.D., ALAN DONSKY, M.D., MARY J.
GOODMAN, R.N., and ALI MASSUMI, M.D.
Background: Studies indicate
that success of radiofrequency (RF) ablation of atrial fibrillation (AF) may be
in part due to vagal denervation. RFA of supraventricular tachycardia (SVT) has
been associated with vagal denervation. The effects of slow pathway (SP)
ablation on AF inducibility have not been studied.
Objective: To test the hypothesis that SP ablation renders AF less inducible.
Methods: Consecutive patients referred for SVT were studied. After
atrioventricular nodal reentrant tachycardia (AVNRT) was confirmed they
underwent induction of AF. After SP ablation AF induction was reattempted.
Vulnerability to AF was reassessed.
Results: Twenty-four patients were enrolled; eight were not inducible for AF in
the preablative state. Mean CL of the AVNRT was 340 ± 16 ms. The average RF
ablation time was 131 ± 42 seconds. Presence of junctional rhythm was required.
Of the 16 with inducible AF two patients had AF induced during routine invasive
electrophysiology study. None of these had inducible AF after SP ablation.
Fourteen of 16 patients required specific AF induction. Ten of these were
noninducible after SP ablation; two were inducible after SP ablation but with a
more aggressive pacing protocol (P < 0.03 compared to preablation) and two had
no change in AF vulnerability. Seven of the eight noninducible patients remained
noninducible for AF post SP ablation. In the 12 patients who were inducible
prior but noninducible after ablation the mean atrial effective refractory
period (AERP) increased for both BCL at 400 and 600 ms (400/216 ± 8 ms
preablation vs 400/248 ± 12 ms postablation, P < 0.03; 600/228 ± 8 ms
preablation vs 600/259 ± 6 ms postablation, P < 0.04). There were no significant
changes in AERP of patients who remained inducible or who were noninducible
before ablation. The average ablation time for patients who became noninducible
after ablation was significantly higher than those who had no change in
inducibility or remained inducible but at a more aggressive pacing threshold
(157 ± 24 seconds vs 35 ± 5 seconds; P < 0.005).
Conclusion: SP ablation acutely decreases vulnerability to pacing-induced AF in
patients with AVNRT. This may reflect the effect of ablation on atrial vagal
tone.
Circulation. 2006;114:2317-2324
Frédéric Sacher, MD; Vincent Probst, MD,
PhD; Yoshito Iesaka, MD; Peggy Jacon, MD; Julien Laborderie, MD; Frédérique
Mizon-Gérard, MD; Philippe Mabo, MD; Sylvain Reuter, MD; Dominique Lamaison, MD;
Yoshihide Takahashi, MD; Mark D. O’Neill, MB, BCh, DPhil; Stéphane Garrigue, MD,
PhD; Bertrand Pierre, MD; Pierre Jaïs, MD; Jean-Luc Pasquié, MD, PhD; Mélèze
Hocini, MD; Michèle Salvador-Mazenq, MD; Akihiko Nogami, MD; Alain Amiel, MD;
Pascal Defaye, MD; Pierre Bordachar, MD; Serge Boveda, MD; Philippe Maury, MD;
Didier Klug, MD, PhD; Dominique Babuty, MD, PhD; Michel Haïssaguerre, MD;
Jacques Mansourati, MD; Jacques Clémenty, MD; Hervé Le Marec, MD, PhD
Background— Brugada syndrome
is an arrhythmogenic disease characterized by an increased risk of sudden
cardiac death (SCD) by ventricular fibrillation. At present, an implantable
cardioverter-defibrillator (ICD) is the recommended therapy in high-risk
patients. This multicenter study reports the outcome of a large series of
patients implanted with an ICD for Brugada syndrome.
Methods and Results— All patients (n=220, 46±12 years, 183 male) with a type 1
Brugada ECG pattern implanted with an ICD in 14 centers between 1993 and 2005
were investigated. ICD indication was based on resuscitated SCD (18 patients,
8%), syncope (88 patients, 40%), or positive electrophysiological study in
asymptomatic patients (99 patients, 45%). The remaining 15 patients received an
ICD because of a family history of SCD or nonsustained ventricular arrhythmia.
During a mean follow-up of 38±27 months, no patient died and 18 patients (8%)
had appropriate device therapy (10±15 shocks/patient, 26±33 months after
implantation). The complication rate was 28%, including inappropriate shocks,
which occurred in 45 patients (20%, 4±3 shocks/patient, 21±20 months after
implantation). The reasons for inappropriate therapy were lead failure (19
patients), T-wave oversensing (10 patients), sinus tachycardia (10 patients),
and supraventricular tachycardia (9 patients). Among implantation parameters,
high defibrillation threshold, high pacing threshold, and low R-wave amplitude
occurred, respectively, in 12%, 27%, and 15% of cases.
Conclusion— In this large Brugada
syndrome population, a low incidence of arrhythmic events was found, with an
annual event rate of 2.6% during a follow-up of >3 years, in addition to a
significant risk of device-related complications (8.9%/year).
Inappropriate shocks were 2.5 times more frequent than appropriate ones.
PACE 2006; 29:1044–1054
JANEK SENARATNE, MARLEEN E. IRWIN, R.R.T.,
F.H.R.S., and MANOHARA P. J. SENARATNE, F.A.C.C., PH.D.
Background: Although
pacemaker manufacturers provide projections on longevity, these projections
cannot be relied upon due to the assumptions of output parameters being far in
excess of those programmed in clinical practice.
Objective: The purpose of this review was to compare the actual longevity to the
calculated longevity of pacemakers based on battery cell characteristics taking
into account individual programmed parameters, mode, degree of usage, and
percent pacing. This was also compared to the manufacturers' own projected
longevities.
Methods: Patients who had a pacemaker replaced between 1998 and 2003 were
included (n = 124). Cell characteristics were obtained from manufacturers and
programmed parameters were obtained at each visit. Stepwise calculations were
done for each visit to find current drain during each interval, and then were
used in a weighted average to find the total average lifetime current drain.
This was subsequently used to find a calculated longevity for each pacemaker to
be compared to the actual longevity observed.
Results: The pacemakers lasted 491 ± 92 days (mean ± SEM) less than calculated.
There was also a difference between dual- and single-chamber devices (though not
statistically significant). Moreover, it was found that there were significant
differences between manufacturers.
Conclusions: There appears to be a significant discrepancy between calculated
and actual longevities, confirming that battery depletion occurs earlier than
expected. This suggests that current drain expended for ancillary functions may
be considerable. Another factor may be pre-implantation drain. Vigilance with
programming of outputs, modes, sensors, heart rates, and ancillary functions
could potentially extend longevity and postpone/obviate the need for costly
repeat surgery with its attended risk of complications. Furthermore, the
differences between manufacturers seem to parallel the clinical impressions.
Eur Heart J 27: 2440-2447
Carla Giustetto, Fernando Di Monte,
Christian Wolpert, Martin Borggrefe, Rainer Schimpf, Pascal Sbragia, Gianpiero
Leone, Philippe Maury, Olli Anttonen6, Michel Haissaguerre and Fiorenzo Gaita
Aims Clinical presentation,
occurrence of sudden infant death, and results of the available therapies in the
largest group of patients with short QT syndrome (SQTS), studied so far, are
reported.
Methods and results Clinical history, physical examination, electrocardiogram
(ECG), exercise stress testing, electrophysiological study, morphological
evaluation, genetic analysis and therapy results in 29 patients with SQTS and
personal and/or familial history of cardiac arrest are reported. The median age
at diagnosis was 30 years (range 4–80). In all subjects, structural heart
disease was excluded. Eighteen patients were symptomatic (62%): 10 had cardiac
arrest (34%) and in 8 (28%) this was the first clinical presentation. Cardiac
arrest had occurred in the first months of life in two patients. Seven patients
had syncope (24%); 9 (31%) had palpitations with atrial fibrillation documented
even in young subjects. At ECG, patients exhibited a QT interval 320 ms and QTc
340 ms. Fourteen patients received an implantable cardioverter-defibrillator
(ICD) and 10 hydroquinidine prophylaxis. At a median follow-up of 23 months
(range 9–49), one patient received an appropriate shock from the ICD; no patient
on hydroquinidine had sudden death or syncope.
Conclusion SQTS carries a high risk of sudden death and may be a cause of death
in early infancy. ICD is the first choice therapy; hydroquinidine may be
proposed in children and in the patients who refuse the implant.
Circulation. 2006;114:1676-1681
Antoine Da Costa, MD, PhD; Jérôme Thévenin,
MD; Frédéric Roche, MD, PhD; Cécile Romeyer-Bouchard, MD; Loucif Abdellaoui, MD;
Marc Messier, PhD; Lucien Denis, MD; Emmanuel Faure, MD; Régis Gonthier, MD;
Georges Kruszynski, MD; J. Marie Pages, MD; Serge Bonijoly, MD; Dominique
Lamaison, MD; Pascal Defaye, MD; J. Claude Barthélemy, MD, PhD; Thierry Gouttard,
MD; Karl Isaaz, MD, FESC, for the Loire-Ardèche-Drôme-Isère-Puy-de-Dôme (LADIP)
Trial of Atrial Flutter Investigators
Background— There is no
published randomized study comparing amiodarone therapy and radiofrequency
catheter ablation (RFA) after only 1 episode of symptomatic atrial flutter
(AFL). The aim of the Loire-Ardèche-Drôme-Isère-Puy-de-Dôme (LADIP) Trial of
Atrial Flutter was 2-fold: (1) to prospectively compare first-line RFA (group I)
versus cardioversion and amiodarone therapy (group II) after only 1 AFL episode;
and (2) to determine the impact of both treatments on the long-term risk of
subsequent atrial fibrillation (AF).
Methods and Results— From October 2002 to February 2006, 104 patients (aged 78±5
years; 20 women) with AFL were included, with 52 patients in group I and 52
patients in group II. The cumulative risk of AFL or AF was interpreted with the
use of Kaplan-Meier curves and compared by the log-rank test. Clinical
presentation, echocardiographic data, and follow-up were as follows: age (78.5±5
versus 78±5 years), history of AF (27% versus 21.6%); structural heart disease
(58% versus 65%), left ventricular ejection fraction (56±14% versus 54.5±14%),
left atrial size (43±7 versus 43±6 mm), mean follow-up (13±6 versus 13±6 months;
P=NS), recurrence of AFL (3.8% versus 29.5%; P<0.0001), and occurrence of
significant AF beyond 10 minutes (25% versus 18%; P=0.3). Five complications
(10%) were noted in group II (sick sinus syndrome in 2, hyperthyroidism in 1,
and hypothyroidism in 2) and none in group I (0%) (P=0.03).
Conclusions— RFA should be considered a
first-line therapy even after the first episode of symptomatic AFL. There
is a better long-term success rate, the same risk of subsequent AF, and fewer
secondary effects.
PACE 2006; 29:1069–1074
MASAYUKI SHIMANO, M.D., YASUYA INDEN,
M.D., YUKIHIKO YOSHIDA, M.D., YUKIOMI TSUJI, M.D., NAOYA TSUBOI, M.D., TARO
OKADA, M.D., TAKUMI YAMADA, M.D., YOSHIMASA MURAKAMI, M.D., YASUNOBU TAKADA,
M.D., HARUO HIRAYAMA, M.D., and TOYOAKI MUROHARA, M.D.
Background and Objectives:
The left ventricular (LV) stimulation site is currently recommended to position
the lead at the lateral wall. However, little is known as to whether right
ventricular (RV) lead positioning is also important for cardiac
resynchronization therapy. This study compared the acute hemodynamic response to
biventricular pacing (BiV) at two different RV stimulation sites: RV high septum
(RVHS) and RV apex (RVA).
Methods and Results: Using micro-manometer-tipped catheter, LV pressure was
measured during BiV pacing at RV (RVA or RVHS) and LV free wall in 33 patients.
Changes in LV dP/dtmax and dP/dtmin from baseline were compared between RVA and
RVHS. BiV pacing increased dP/dtmax by 30.3 ± 1.2% in RVHS and by 33.3 ± 1.7% in
RVA (P = n.s.), and decreased dP/dtmin by 11.4 ± 0.7% in RVHS and by 13.0 ± 1.0%
in RVA (P = n.s.). To explore the optimal combination of RV and LV stimulation
sites, we assessed separately the role of RV positioning with LV pacing at
anterolateral (AL), lateral (LAT), or posterolateral (PL) segment. When the LV
was paced at AL or LAT, the increase in dP/dtmax with RVHS pacing was smaller
than that with RVA pacing (AL: 12.2 ± 2.2% vs 19.3 ± 2.1%, P < 0.05; LAT: 22.0 ±
2.7% vs 28.5 ± 2.2%, P < 0.05). There was no difference in dP/dtmin between RVHS-
and RVA pacing in individual LV segments.
Conclusions: RVHS stimulation has no
overall advantage as an alternative stimulation site for RVA during BiV pacing.
RVHS was equivalent with RVA in combination with the PL LV site, while RVA was
superior to RVHS in combination with AL or LAT LV site.
Europace 8: 935-942.
Isabelle C. Van Gelder, D. George Wyse,
Mary L. Chandler, Howard A. Cooper, Brian Olshansky, Vincent E. Hagens, Harry
J.G.M. Crijns, the RACE and AFFIRM Investigators
We examined whether strict
rate control offers benefit over more lenient rate control.
Methods and Results We compared the outcome of patients enrolled in the
rate-control arms of AFFIRM and RACE, using data from patients who met a
composite of overlapping inclusion and exclusion criteria. We evaluated 1091
patients, 874 from AFFIRM and 217 from RACE. In
AFFIRM, the rate-control strategy
aimed for a resting heart rate 80 bpm
and heart rate during daily activity of
110 bpm. In RACE, a more
lenient approach was taken: resting
heart rate <100 bpm. Primary endpoint was a composite of mortality,
cardiovascular hospitalization, and myocardial infarction. Mean heart rate
across all follow-up visits for patients in AF was lower in AFFIRM (76.1 vs.
83.4 bpm). Event-free survival for the occurrence of the primary endpoint did
not differ (64% in AFFIRM vs. 66% in RACE). Patients with mean heart rates
during AF within the AFFIRM ( 80) or RACE (<100) criteria had a better outcome
than patients with heart rates 100 (hazard ratios 0.69 and 0.58, respectively,
for 80 and <100 compared with 100 bpm).
Conclusion Stringency of the approach to
rate control, based on the comparison of the AFFIRM and RACE studies, was not
associated with an important difference in clinical events.
Europace 8: 855-858.
Igor Zupan, Luka Lipar1, David i ek, Wim
Boute, Ma a Vidmar, Tone Gabrijel i, Peter Rakovec and Ale Brecelj
Methods and results We
implanted single-lead VDD pacemakers in patients with isolated atrioventricular
block and performed a retrospective analysis of 307 patients who had their
devices implanted between May 1994 and September 2001. In 39 patients (12.7%),
the pacing mode had to be reprogrammed to a single-chamber ventricular pacing
mode, mostly due to permanent AT. In 16 of these patients, the atrial sensing
safety margin was less than 150%. The atrial sensing safety margin was
insufficient, i.e. less than 100% in only seven patients. Although only 12
(3.9%) of the patients had a history of paroxysmal AT at the time of pacemaker
implantation, 200 (65%) patients presented with AT during follow-up. The mean AT
burden at the last follow-up was 2.5%.
Conclusion These data illustrate that single-lead VDD pacemakers can be applied
without serious complications in a highly selected group of patients. Our main
concern is the development of AT in a large part of our population. Over a
10-year period, two thirds of our patients presented with AT.
J Am Coll Cardiol 48: 1652-1657
Nynke van Dijk, Fabio Quartieri, Jean-Jaques
Blanc, Roberto Garcia-Civera, Michele Brignole, Angel Moya, Wouter Wieling, and
on behalf of the PC-Trial Investigators
OBJECTIVES: In this study, we
assessed the effectiveness of physical counterpressure maneuvers (PCM) in daily
life.
BACKGROUND: There is presently no evidence-based therapy for vasovagal syncope.
Current treatment consists of explanation and life-style advice. Physical
counterpressure maneuvers have been shown to raise blood pressure and to control
or abort vasovagal episodes in laboratory conditions.
METHODS: We performed a multicenter, prospective, randomized clinical trial,
which included 223 patients age 38.6 (±15.4) years with recurrent vasovagal
syncope and recognizable prodromal symptoms. One hundred and seventeen patients
were randomized to standardized conventional therapy alone, and 106 patients
received conventional therapy plus training in PCM.
RESULTS: The median yearly syncope burden during follow-up was significantly
lower in the group trained in PCM than in the control group (p = 0.004). During
a mean follow-up period of 14 months, overall 50.9% of the patients with
conventional treatment and 31.6% of the patients trained in PCM experienced a
syncopal recurrence (p = 0.005). Actuarial recurrence-free survival was better
in the treatment group (log-rank p = 0.018), resulting in a relative risk
reduction of 39% (95% confidence interval, 11% to 53%). No adverse events were
reported.
CONCLUSIONS: Physical counterpressure maneuvers are a risk-free, effective, and
low-cost treatment method in patients with vasovagal syncope and recognizable
prodromal symptoms, and should be advised as first-line treatment in patients
presenting with vasovagal syncope with prodromal symptoms.
J Am Coll Cardiol 48: 1378-1384
Jiyoong Kim, MD, Akiko Ogai, MS, Satoshi
Nakatani, MD, PhD, Kazuhiko Hashimura, MD, Hideaki Kanzaki, MD, Kazuo Komamura,
MD, PhD, Masanori Asakura, MD, PhD, Hiroshi Asanuma, MD, PhD, Soichiro Kitamura,
MD, PhD, Hitonobu Tomoike, MD, PhD and Masafumi Kitakaze, MD, PhD
OBJECTIVES: The goal of this
work was to determine whether the blockade of histamine H2 receptors is
beneficial for the pathophysiology of chronic heart failure (CHF).
BACKGROUND: Because CHF is one of the major life-threatening diseases, we need
to find a novel effective therapy. Intriguingly, our previous study, which
predicts the involvement of histamine in CHF, suggests that we should test this
hypothesis in patients with CHF.
METHODS: We selected 159 patients who received famotidine among symptomatic CHF
patients for the retrospective study. We blindly selected age- and
gender-matched CHF patients receiving drugs for gastritis other than histamine
H2 receptor blockers as a control group. For the prospective study, 50
symptomatic CHF patients were randomly divided into 2 groups. One group received
famotidine of 30 mg/day for 6 months, and the other group received teprenone.
RESULTS: In the retrospective study, famotidine of 20 to 40 mg decreased both
left ventricular end-diastolic and end-systolic lengths (LVDd and LVDs,
respectively) and the plasma B-type natriuretic peptide (BNP) levels (182 ± 21
vs. 259 ± 25 pg/ml, p < 0.05) with unaltered fractional shortening (FS). In a
randomized, open-label study, compared with teprenone, famotidine of 30 mg
prospectively decreased both New York Heart Association functional class (p <
0.05) and plasma BNP levels (183 ± 26 pg/ml vs. 285 ± 41 pg/ml, p < 0.05); this
corresponded to decreasing both LVDd (57 ± 2 mm vs. 64 ± 2 mm, p < 0.05) and
LVDs (47 ± 2 mm vs. 55 ± 2 mm, p < 0.05) with unaltered FS (15 ± 1% vs. 17 ±
1%). The frequency of readmission because of worsening of CHF was lower in the
famotidine group (4% and 24%, p < 0.05). On the other hand, teprenone had no
effects on CHF.
CONCLUSIONS: Famotidine improved both
cardiac symptoms and ventricular remodeling associated with CHF.
Histamine H2 receptor blockers may have therapeutic benefits for CHF.
Circulation. 2006;114:1829-1837
Ewa A. Jankowska, MD, PhD; Bartosz Biel,
MD; Jacek Majda, PhD; Alicja Szklarska, PhD; Monika Lopuszanska, MSc; Marek
Medras, MD, PhD; Stefan D. Anker, MD, PhD; Waldemar Banasiak, MD, PhD; Philip A.
Poole-Wilson, MD, FRCP; Piotr Ponikowski, MD, PhD
Background— The age-related
decline of circulating anabolic hormones in men is associated with increased
morbidity and mortality. We studied the prevalence and prognostic consequences
of deficiencies in circulating total testosterone (TT) and free testosterone,
dehydroepiandrosterone sulfate (DHEAS), and insulin-like growth factor-1 (IGF-1)
in men with chronic heart failure (CHF).
Methods and Results— Serum levels of TT, DHEAS, and IGF-1 were measured with
immunoassays in 208 men with CHF (median age 63 years; median left ventricular
ejection fraction 33%; New York Heart Association class I/II/III/IV,
19/102/70/17) and in 366 healthy men. Serum levels of free testosterone were
estimated (eFT) from levels of TT and sex hormone binding globulin. Deficiencies
in DHEAS, TT, eFT, and IGF-1, defined as serum levels at or below the 10th
percentile of healthy peers, were seen across all age categories in men with
CHF. DHEAS, TT, and eFT were inversely related to New York Heart Association
class irrespective of cause (all P<0.01). DHEAS correlated positively with left
ventricular ejection fraction and inversely with N-terminal pro-brain
natriuretic peptide (both P<0.01). Circulating TT, eFT, DHEAS, and IGF-1 levels
were prognostic markers in multivariable models when adjusted for established
prognostic factors (all P<0.05). Men with CHF and normal levels of all anabolic
hormones had the best 3-year survival rate (83%, 95% CI 67% to 98%) compared
with those with deficiencies in 1 (74% survival rate, 95% CI 65% to 84%), 2 (55%
survival rate, 95% CI 45% to 66%), or all 3 (27% survival rate, 95% CI 5% to
49%) anabolic endocrine axes (P<0.0001).
Conclusions— In male CHF patients,
anabolic hormone depletion is common, and a deficiency of each anabolic
hormone is an independent marker of poor
prognosis. Deficiency of >1 anabolic hormone identifies groups with a
higher mortality.
Circulation 2006, Circulation
2006;114 1455-1461
Giuseppe Patti MD, Massimo Chello MD,
Dario Candura MD, Vincenzo Pasceri MD, Andrea D’Ambrosio MD, Elvio Covino MD,
and Germano Di Sciascio MD
Background--Atrial
fibrillation (AF) after cardiac surgery is associated with increased risk of
complications, length of stay, and cost of care. Observational evidence suggests
that patients who have undergone previous statin therapy have a lower incidence
of postoperative AF. We tested this observation in a randomized, controlled
trial.
Methods and Results--Two hundred patients undergoing elective cardiac surgery
with cardiopulmonary bypass, without previous statin treatment or history of AF,
were enrolled. Patients were randomized to atorvastatin (40 mg/d, n=101) or
placebo (n=99) starting 7 days before operation. The primary end point was
incidence of postoperative AF; secondary end points were length of stay, 30-day
major adverse cardiac and cerebrovascular events, and postoperative C-reactive
protein (CRP) variations. Atorvastatin significantly reduced the incidence of AF
versus placebo (35% versus 57%, P=0.003). Accordingly, length of stay was longer
in the placebo versus atorvastatin arm (6.9±1.4 versus 6.3±1.2 days, P=0.001).
Peak CRP levels were lower in patients without AF (P=0.01), irrespective of
randomization assignment. Multivariable analysis showed that atorvastatin
treatment conferred a 61% reduction in
risk of AF (odds ratio 0.39, 95% confidence interval 0.18 to 0.85,
P=0.017), whereas high postoperative CRP levels were associated with increased
risk (odds ratio 2.0, 95% confidence interval 1.2 to 7.0, P=0.01). The incidence
of major adverse cardiac and cerebrovascular events at 30 days was similar in
the 2 arms.
Conclusions--Treatment with atorvastatin 40 mg/d, initiated 7 days before
surgery, significantly reduces the incidence of postoperative AF after elective
cardiac surgery with cardiopulmonary bypass and shortens hospital stay. These
results may influence practice patterns with regard to adjuvant pharmacological
therapy before cardiac surgery.
J Am Coll Cardiol 48: 1228-1233
Jeffrey J. Goldberger, MD, FACC, Haris
Subacius, MA, Andi Schaechter, RN, Adam Howard, BA, Ronald Berger, MD, PhD, FACC
, Alaa Shalaby, MD, FACC , Joseph Levine, MD , Alan H. Kadish, MD, FACC for the
DEFINITE Investigators
OBJECTIVES: We sought to
evaluate whether statins were associated with a survival benefit and significant
attenuation in life-threatening arrhythmias in patients with nonischemic dilated
cardiomyopathy.
BACKGROUND: Statins are associated with a reduction in appropriate implantable
cardioverter-defibrillator (ICD) therapy in patients with coronary artery
disease and improved clinical status in nonischemic dilated cardiomyopathy.
METHODS: The effect of statin use on time to death or resuscitated cardiac
arrest and time to arrhythmic sudden death was evaluated in 458 patients
enrolled in the DEFINITE (DEFIbrillators in Non-Ischemic cardiomyopathy
Treatment Evaluation) study. The effect of statin use on time to first
appropriate shock was analyzed only in the 229 patients who were randomized to
ICD therapy.
RESULTS: The unadjusted hazard ratio (HR) for death among patients on versus
those not on statin therapy was 0.22 (95% confidence interval [CI] 0.09 to 0.55;
p = 0.001). When controlled for statin effects, ICD therapy was associated with
improved survival (HR 0.61; 95% CI 0.38 to 0.99; p = 0.04). There was one
arrhythmic sudden death in the 110 patients receiving statin therapy (0.9%)
versus 18 of 348 patients not receiving statins (5.2%; p = 0.04). The unadjusted
HR for arrhythmic sudden death among patients on versus those not on statin
therapy was 0.16 (95% CI 0.022 to 1.21; p = 0.08). The HR for appropriate shocks
among patients on versus those not on statin therapy was 0.78 (95% CI 0.34 to
1.82) after adjustment for baseline differences in the two groups.
CONCLUSIONS: Statin use in the DEFINITE study was associated with a
78% reduction in mortality. This
reduction was caused, in part, by a reduction in arrhythmic sudden death. These
findings should be confirmed in a prospective, randomized clinical trial.
Heart Rhythm Volume 3, Issue 9,
Pages 1010-1016 (September 2006)
Sumeet K. Mainigi, MD, Joshua M. Cooper,
MD, Andrea M. Russo, MD, Hemal M. Nayak, MD, David Lin, MD, Sanjay Dixit, MD,
Edward P. Gerstenfeld, MD, Henry H. Hsia, MD, David J. Callans, MD, Francis E.
Marchlinski, MD, Ralph J. Verdino, MD
Background
The biventricular implantable cardioverter-defibrillator (ICD) is an important
therapy for select patients with severe heart failure. Given reported risk
factors for elevated defibrillation thresholds (DFTs), patients undergoing
biventricular ICD placement would be suspected of having a higher incidence of
elevated DFT.
Objectives
The purpose of this study was to examine the clinical predictors and mortality
risk of elevated DFTs in patients receiving a biventricular ICD.
Methods
Characteristics of patients undergoing biventricular ICD placement with an
elevated DFT were compared to those without an elevated DFT.
Results
An elevated DFT was found in 14 (12%) of 121 patients. Mean QRS duration was 210
± 50 ms in the elevated DFT group and 171 ± 36 ms in the normal DFT group (P =
.01). Patients with a QRS duration ≥200 ms were more likely to have an elevated
DFT than those with a duration <200 ms (odds ratio 13.4, 95% confidence interval
3.1–66.7, P <.01). No other clinical characteristics were associated with an
elevated DFT. More than 90% of patients with an elevated DFT achieved an
adequate safety margin through system modification or manipulation of their drug
regimen. An elevated DFT did not have an impact on 2-year mortality.
Conclusion
Patients with a biventricular ICD had a
12% incidence of elevated DFT in our sequential patient cohort.
QRS duration prior to biventricular ICD
placement is the most powerful predictor of patients at risk for an elevated DFT.
An elevated DFT does not have an impact on mortality, perhaps because of
successful implementation of system modifications to ensure an adequate
defibrillation safety margin.
J Cardiovasc Electrophysiol, Vol.
17, pp. 1080-1085, October 2006
AAMIR CHEEMA, M.D., JUN DONG, M.D., PH.D.,
DARSHAN DALAL, M.D., M.P.H., CHANDRASEKHAR R. VASAMREDDY, M.D., JOSEPH E.
MARINE, M.D., CHARLES A. HENRIKSON, M.D.* DAVID SPRAGG, M.D., ALAN CHENG, M.D.,
SAMAN NAZARIAN, M.D., SUNIL SINHA, M.D., HENRY HALPERIN, M.D., M.A., RONALD
BERGER, M.D., PH.D., and HUGH CALKINS, M.D.
Background: Each of the two
main approaches to catheter ablation of atrial fibrillation (AF, segmental and
circumferential) is associated with moderate long-term efficacy.
Objective: To report the long-term outcomes of a modified technique that
combines circumferential ablation with pulmonary vein (PV) isolation, determined
by a circular mapping catheter and to determine the relationship between
complete PV isolation and long-term efficacy.
Methods: The patient population was composed of 64 consecutive patients (47 men
[73%]; age 59 ± 11 years) with AF who underwent catheter ablation. AF was
paroxysmal in 29 (45%) and nonparoxysmal in 35 (55%). Each patient was followed
for a minimum of 12 months.
Results: After a mean follow-up of 13 ± 1 months, the long-term single-procedure
success rate was 45% (n = 29) with an additional 4% (n = 3) of patients
demonstrating improvement. With repeat procedures in 19 patients, the overall
long-term success rate was 62% (n = 40) with 9% (n = 6) demonstrating
improvement. All the patients who underwent repeat ablations had recovered PV
conduction. Incomplete PV isolation was the only independent predictor of
failure. A major complication occurred in four (6%) patients, including three
patients with vascular complications and one with cardiac tamponade.
Conclusion: Our results suggest that the
long-term single-procedure efficacy of circumferential ablation with PV
isolation in a cohort of patients with predominantly nonparoxysmal AF approaches
50%. Repeat procedures involving re-isolation of the PVs result in a
significant improvement in outcomes. Complete electrical isolation of the PVs
has a significant impact on the long-term efficacy of the procedure.
J Am Coll Cardiol 48: 1198-1205
Arthur M. Feldman, MD, PhD, FACC, Marc A.
Silver, MD, FACC , Gary S. Francis, MD, FACC , Charles W. Abbottsmith, MD, FACC
, Bruce L. Fleishman, MD, FACC, Ozlem Soran, MD, MPH, FACC, FESC, Paul-Andre de
Lame, MD, Thomas Varricchione, MBA, RRT for the PEECH Investigators
OBJECTIVES: The PEECH
(Prospective Evaluation of Enhanced External Counterpulsation in Congestive
Heart Failure) study assessed the benefits of enhanced external counterpulsation
(EECP) in the treatment of patients with mild-to-moderate heart failure (HF).
BACKGROUND: Enhanced external counterpulsation reduced angina symptoms and
extended time to exercise-induced ischemia in patients with coronary artery
disease, angina, and normal left ventricular function. A small pilot study and
registry analysis suggested benefits in patients with HF.
METHODS: We randomized 187 subjects with mild-to-moderate symptoms of HF to
either EECP and protocol-defined pharmacologic therapy (PT) or PT alone. Two
co-primary end points were pre-defined: the percentage of subjects with a 60 s
or more increase in exercise duration and the percentage of subjects with at
least 1.25 ml/min/kg increase in peak volume of oxygen uptake (VO2) at 6 months.
RESULTS: By the primary intent-to-treat analysis, 35% of subjects in the EECP
group and 25% of control subjects increased exercise time by at least 60 s (p =
0.016) at 6 months. However, there was no between-group difference in peak VO2
changes. New York Heart Association (NYHA) functional class improved in the
active treatment group at 1 week (p < 0.01), 3 months (p < 0.02), and 6 months
(p < 0.01). The Minnesota Living with Heart Failure score improved significantly
1 week (p < 0.02) and 3 months after treatment (p = 0.01).
CONCLUSIONS: In this randomized, single-blinded study, EECP improved exercise
tolerance, quality of life, and NYHA functional classification without an
accompanying increase in peak VO2.
PACE 2006; 29:946–952
CHRISTOF KOLB, ISABEL DEISENHOFER,
SEBASTIAN SCHMIEDER, PETRA BARTHEL, BERNHARD ZRENNER, MARTIN R. KARCH, and CLAUS
SCHMITT
Introduction: In patients who
have an indication for an implantable cardioverter defibrillator (ICD) a
dual-chamber device is indicated in the case of concomitant significant sinus
node disease or atrioventricular block. It is a matter of debate whether
dual-chamber ICD may be beneficial for patients with preserved sinus and
atrioventricular nodal function as data from prospective randomized trials are
limited. Mid- or long-term follow-up data are unavailable.
Methods and Results: One hundred patients (age 60 ± 12 years, 11 women) with the
indication for the implantation of an ICD and without antibradycardia pacing
indication were randomly assigned to either receive a dual-chamber ICD (n = 52)
or a single-chamber ICD (n = 48). Patients were followed-up for a mean of 52 ±
14 months. Mortality and arrhythmogenic morbidity were assessed.
All-cause mortality was 21% for single-chamber and 31% for dual-chamber ICD
recipients, respectively (P = 0.26). Cardiovascular mortality was 13% for
single-chamber ICD recipients versus 21% in the dual-chamber group (P = 0.25).
Subgroup analysis using 35% of ventricular paced beats as cutoff value in the
dual-chamber ICD group revealed a 42% mortality rate for the patients with
frequent ventricular pacing compared to 10% of patients with a low rate of
ventricular pacing (P = 0.05, relative risk 4.21, 95% confidence interval:
0.9–19.8). As for arrhythmogenic morbidity, the difference in the ventricular
tachyarrhythmia load was not different in both groups (single chamber: 23 ± 74
VT episodes, dual chamber: 54 ± 134 VT episodes, P = 0.17).
Conclusion: In ICD recipients without conventional indication for dual-chamber
pacing, dual chamber compared to single-chamber ICD has
no advantage concerning mortality and
arrhythmogenic morbidity in a long-term follow-up. In these patients the
implantation of a single-chamber device is sufficient.
J Am Coll Cardiol 48: 1225-1227
Aidan P. Bolger, BSc, MRCP, Frederick R.
Bartlett, MBBS , Helen S. Penston, SRN , Justin O’Leary, BSc, DMU, Noel Pollock,
MBBS , Raffi Kaprielian, MD, MRCP and Callum M. Chapman, MRCP
OBJECTIVES: This study was
undertaken to assess the hematologic, clinical, and biochemical response to
intravenous iron in patients with chronic heart failure (CHF) and anemia.
BACKGROUND: Anemia is common in patients with CHF and is associated with higher
morbidity and mortality. The combination of erythropoietin (EPO) and iron
increases hemoglobin (Hb) and improves symptoms and exercise capacity in anemic
CHF patients. It is not known whether intravenous iron alone is an effective
treatment for anemia associated with CHF.
METHODS: Sixteen anemic patients (Hb 12 g/dl) with stable CHF (age 68.3 ± 11.5
years, 12 men, 9 participants New York Heart Association [NYHA] functional class
II and the remainder class III, left ventricular ejection fraction 26 ± 13%)
received a maximum of 1 g of iron sucrose by bolus intravenous injections over a
12-day treatment phase in an outpatient setting. Mean follow-up was 92 ± 6 days.
RESULTS: Hemoglobin rose from 11.2 ± 0.7 to 12.6 ± 1.2 g/dl (p = 0.0007),
Minnesota Living with Heart Failure (MLHF) score fell (denoting improvement)
from 33 ± 19 to 19 ± 14 (p = 0.02), 6-min walk distance increased from 242 ± 78
m to 286 ± 72 m (p = 0.01), and all patients recorded NYHA class II at study end
(p < 0.02). Changes in MLHF score and 6-min walk distance related closely to
changes in Hb (r = 0.76, p = 0.002; r = 0.56, p = 0.03, respectively). Of all
baseline measurements, only iron and transferrin saturation correlated with
increases in Hb (r = 0.60, p = 0.02; r = 0.60, p = 0.01, respectively). There
were no adverse events relating to drug administration or during follow-up.
CONCLUSIONS: Intravenous iron sucrose, when used without concomitant EPO, is a
simple and safe therapy that increases Hb, reduces symptoms, and improves
exercise capacity in anemic patients with CHF. Further assessment of its
efficacy should be made in a multicenter, randomized,
placebo-controlled trial.
Circulation. 2006;114:1140-1145
Lukas R.C. Dekker, MD, PhD; Connie R.
Bezzina, PhD; José P.S. Henriques, MD, PhD; Michael W. Tanck, PhD; Karel T.
Koch, MD, PhD; Marco W. Alings, MD, PhD; Alfred E.R. Arnold, MD, PhD; Menko-Jan
de Boer, MD, PhD; Anton P.M. Gorgels, MD, PhD; H. Rolf Michels, MD, PhD; Agnes
Verkerk, BSc; Freek W.A. Verheugt, MD, PhD; Felix Zijlstra, MD, PhD; Arthur A.M.
Wilde, MD, PhD
Background— Primary
ventricular fibrillation (VF) accounts for the majority of deaths during the
acute phase of myocardial infarction. Identification of patients at risk for
primary VF remains very poor.
Methods and Results— We performed a case-control study in patients with a first
ST-elevation myocardial infarction (STEMI) to identify independent risk factors
for primary VF. A total of 330 primary VF survivors (cases) and 372 controls
were included; patients with earlier infarcts or signs of structural heart
disease were excluded. Baseline characteristics, including age, gender, drug
use, and ECG parameters registered well before the index infarction, as well as
medical history, were not different. Infarct size and location, culprit coronary
artery, and presence of multivessel disease were similar between groups.
Analysis of ECGs performed at hospital admission for the index STEMI revealed
that cumulative ST deviation was significantly higher among cases (OR per 10-mm
ST deviation 1.59, 95% CI 1.25 to 2.02). Analysis of medical histories among
parents and siblings showed that the prevalence of cardiovascular disease was
similar between cases and controls (73.1% and 73.0%, respectively); however,
familial sudden death occurred significantly more frequently among cases than
controls (43.1% and 25.1%, respectively; OR 2.72, 95% CI 1.84 to 4.03).
Conclusions— In a population of STEMI patients, the risk of primary VF is
determined by cumulative ST deviation and family history of sudden death.
Journal of Cardiovascular
Electrophysiology Volume 17 Page 931 - September 2006
ILAN GOLDENBERG, M.D., ARTHUR J. MOSS,
M.D., SCOTT MCNITT, M.S., WOJCIECH ZAREBA, M.D., PH.D., JAMES P. DAUBERT, M.D.,
W. JACKSON HALL, PH.D., and MARK L. ANDREWS, B.B.S. for the Multicenter
Automatic Defibrillator Implantation Trial-II Investigators
Introduction: Nicotine
elevates serum catecholamine concentration and is therefore potentially
arrhythmogenic. However, the effect of cigarette smoking on arrhythmic risk in
coronary heart disease patients is not well established.
Methods and Results: The risk of appropriate and inappropriate defibrillator
therapy by smoking status was analyzed in 717 patients who received an
implantable cardioverter defibrillator (ICD) in the Multicenter Automatic
Defibrillator Implantation Trial-II. Compared with patients who had quit smoking
before study entry (past smokers) and patients who had never smoked (never
smokers), patients who continued smoking (current smokers) were significantly
younger and generally had more favorable baseline clinical characteristics.
Despite this, the adjusted hazard ratio (HR) for appropriate ICD therapy for
fast ventricular tachycardia (at heart rates ≥180 b.p.m) or ventricular
fibrillation was highest among current smokers (HR = 2.11 [95% CI 1.11–3.99])
and intermediate among past smokers (HR = 1.57 [95% CI 0.95–2.58]), as compared
with never smokers (P for trend = 0.02). Current smokers also exhibited a higher
risk of inappropriate ICD shocks (HR = 2.93 [95% CI 1.30–6.63]) than past (HR =
1.91 [95% CI 0.97–3.77]) and never smokers (P for trend = 0.008).
Conclusions: In patients with ischemic left ventricular dysfunction, continued
cigarette smoking is associated with a significant increase in the risk of
life-threatening ventricular tachyarrhythmias and inappropriate ICD shocks
induced by rapid supraventricular arrhythmias. Our findings stress the
importance of complete smoking cessation in this high-risk population.
Pacing and Clinical
Electrophysiology Volume 29 Page 880 - August 2006
IBRAHIM MARAI, OSNAT GUREVITZ, SHEMY
CARASSO, EYAL NOF, DAVID BAR-LEV, DAVID LURIA, YARON ARBEL, DOV FREIMARK, MICHA
S. FEINBERG, MICHAEL ELDAR, and MICHAEL GLIKSON
Aims: To compare the clinical
response of patients with right ventricular apical pacing (RVAP) upgraded to
cardiac resynchronization therapy (CRT) to that of previously nonpaced heart
failure (HF) patients who had de novo CRT implantation.
Background: The role of CRT in patients with wide QRS and HF due to RVAP is less
well established than in other CRT candidates.
Methods: Ninety-eight consecutive patients with CRT were studied (mean age 70,
mean ejection fraction 0.23). Group A: patients having RVAP prior to CRT
implantation (n = 25), group B: patients without prior RVAP (n = 73). Clinical
and echocardiographic parameters were recorded prior to, and 3 months after, CRT
implantation.
Results: Group A patients had a wider QRS at baseline compared to group B (203 ±
32 ms vs 163 ± 30 ms respectively, P < 0.001), and a shorter 6-minute walking
distance (222 ± 118 m vs 362 ± 119 m, respectively, P < 0.005). Otherwise,
clinical and echocardiographic parameters were not different. At follow up,
group A patients had an average 0.7 ± 0.5 decrease in their NYHA functional
class, compared to 0.3 ± 0.7 in group B patients (P < 0.05). Six-minute walking
distance increased by 93 ± 113 m in group A, versus 36 ± 120 m in group B (P =
0.22). There was no difference in echocardiographic response to CRT between the
groups.
Conclusions: HF patients with prior RVAP demonstrate clinical improvement after
upgrading to CRT that is comparable, and in some aspects, even better than that
observed in HF patients with native conduction delay who undergo de novo CRT
implantation.
Pacing and Clinical
Electrophysiology Volume 29 Page 875 - August 2006
MARTIN U. BRAUN, THOMAS RAUWOLF, MANIA
BOCK, UTZ KAPPERT, ALESSANDRA BOSCHERI, ANDREAS SCHNABEL, and RUTH H. STRASSER
Background: Permanent
pacemaker implantation usually is contraindicated in patients with systemic
infection. The aim of the present study was to compare two different techniques
of transvenous temporary pacing to bridge the infectious situation until
permanent pacemaker implantation under infection-free conditions is possible.
Methods and Results: Forty-nine patients with systemic infection and
hemodynamic-relevant bradyarrhythmia/asystole were temporarily paced using
either a conventional pacing wire/catheter (n = 26, reference group) or a
permanent bipolar active pacing lead, which was placed transcutaneously in the
right ventricle and connected to an external pacing generator (n = 23, external
lead group). In both groups, there were no significant differences in patient
characteristics. Whereas the sensing values were almost identical, the median
pacing threshold was significantly higher in the reference group (1.0 V vs 0.6
V, P < 0.05). Within comparable duration of pacing (median: 8.2 vs 7.7 days),
there were 24 pacing-related adverse events (including dislocation,
resuscitation due to severe bradycardia, or local infection) in the reference
group as compared to one event in the external lead group (P < 0.01). None of
these complications resulted in cardiac death.
Conclusion: Thus, transvenous pacing with active fixation is safe and associated
with a significantly lower rate of pacing-related adverse events as compared to
the standard technique of transvenous pacing using a passive external pacing
catheter.
Pacing and Clinical
Electrophysiology Volume 29 Page 810 - August 2006
DWARAKRAJ SOUNDARRAJ, RANJAN K. THAKUR,
JOSEPH C. GARDINER, ATUL KHASNIS, and KRIT JONGNARANGSIN
Introduction: Inappropriate
implantable cardioverter defibrillator (ICD) therapy (IT) is a common
complication in patients with ICD. IT is commonly triggered by supraventricular
tachycardias (SVT). Dual chamber ICDs (D-ICDs) may distinguish SVT from
ventricular tachycardia/ventricular fibrillation better than single chamber ICDs
(S-ICDs) and may be associated with a smaller incidence of IT.
Methods: We reviewed the charts of 386 patients who had an ICD implanted for an
AHA class I indication. Intracardiac electrograms were used to classify shocks
as either appropriate or inappropriate.
Results: Of 295 patients with an S-ICD, 66 (22.3%) received IT, compared to 5
(5.4%) of 91 patients with a D-ICD. The likelihood of being event-free at 1, 2,
3, and 4 years was 96.1%, 96.1%, 96.1%, and 89% for patients with D-ICD and
80.7%, 72.7%, 69.6%, and 66.4%, respectively, for patients with S-ICD (P <
0.001). Multivariate analysis showed no significant association with age, sex,
history of atrial fibrillation, history of hypertension, or ejection fraction.
SVTs were the commonest cause of IT in our patients.
Conclusion: Patients with D-ICD are less
likely to receive IT as compared to patients with S-ICD.
Journal of Cardiovascular
Electrophysiology Volume 17 Page 973 - September 2006
CHRISTOPHER REITHMANN, M.D., THOMAS REMP,
M.D., NICO OVERSOHL, M.D., and GERHARD STEINBECK, M.D.
Introduction: Delayed
higher-degree atrioventricular (AV) block can develop after slow pathway
ablation for AV nodal reentrant tachycardia with a preexisting first-degree AV
block. Retrograde fast pathway ablation is considered as an alternative approach
for patients with a markedly prolonged PR interval and no demonstrable
anterograde fast pathway function at baseline. This study aimed to determine the
long-term reliability of AV conduction after retrograde fast pathway ablation in
comparison to slow pathway ablation in patients with AV nodal reentrant
tachycardia and a first-degree AV block at baseline.
Methods and Results: Among 43 patients with AV nodal reentrant tachycardia and a
prolonged PR interval (defined as ≥200 msec), 10 patients without demonstrable
dual pathway physiology underwent ablation of the retrograde fast pathway, and
33 patients with dual pathway physiology underwent slow pathway ablation.
Persisting intraprocedural second- or third-degree AV block requiring pacemaker
implantation occurred in one patient (10%) after retrograde fast pathway
ablation and in one patient (3%) after slow pathway ablation. During the
long-term follow-up of 61 ± 39 months after retrograde fast pathway ablation, no
delayed second- or third-degree AV block occurred, and the PR interval remained
unchanged (308 ± 60 msec vs 304 ± 52 msec). During the follow-up of 37 ± 25
months after slow pathway ablation, a delayed complete heart block developed in
two patients, and a second-degree AV block developed in two patients. Three
patients aged 66, 75, and 76 years died suddenly of unknown cause 4, 16, and 48
months following slow pathway ablation, respectively.
Conclusions: Slow pathway ablation was associated with a significant risk of a
delayed higher-degree AV block in patients with AV nodal reentrant tachycardia
and a prolonged PR interval at baseline.
Retrograde fast pathway ablation for patients with a first-degree AV block and
no demonstrable dual pathway physiology was associated with a higher
intraprocedural risk of complete AV block but did not result in the development
of higher-degree AV block during the long-term follow-up of up to 9 years.
Pacing and Clinical
Electrophysiology Volume 29 Page 858 - August 2006
MICHAEL D. GAMMAGE, RANDY A. LIEBERMAN,
RAYMOND YEE, ANTONIS S. MANOLIS, STEVEN J. COMPTON, CÉSAR KHAZEN, KATIE SCHAAF,
KIMBERLY A. OLESON, and GEORGE H. CROSSLEY FOR THE WORLDWIDE SELECTSECURE
CLINICAL INVESTIGATORS
Purpose: Reduced lead
diameter and reliability can be designed into transvenous permanent pacing leads
through use of redundant insulation and removal of the stylet lumen. The model
3830 lead (Medtronic Inc., Minneapolis, MN, USA) is a bipolar, fixed-screw,
steroid-eluting, lumenless, 4.1-Fr pacing lead. Implantation can be performed in
a variety of right heart sites using a deflectable catheter (Model 10600,
Medtronic). Lead performance and safety were studied.
Methods: Two prospective trials of 338 implanted subjects from 56 global sites
were conducted. Electrical and safety data were obtained at implant,
pre-discharge, and up to 18 months post-implant. Leads were implanted at
traditional and alternate right heart sites.
Results: The study enrolled 338 subjects (204 males, 70.6 ± 11.6 years)
followed-up for a mean of 10.2 months (range, 0–21.6). Mean P-wave amplitudes
ranged from 3.2 mV at 3 months to 2.9 mV at 18 months, while mean atrial pulse
width thresholds at 2.5 V ranged from 0.07 ms at 3 months to 0.09 ms at 18
months. Mean R-wave amplitudes ranged from 11.3 mV to 11.1 mV and mean
ventricular pulse width thresholds at 2.5 V ranged from 0.10 ms to 0.14 ms.
There were 22 ventricular and 12 atrial lead complications within 3 months
post-implant. Survival from lead-related complications improved to a clinically
acceptable rate in the cohort of patients when revised implant techniques were
employed.
Conclusions: With the use of recommended implant techniques, the study results
support the electrical efficacy and safety of a catheter-delivered, lumenless
lead in traditional or alternate right atrium or right ventricle sites through
18 months post-implant.
Journal of Cardiovascular
Electrophysiology Volume 17 Page 992 - September 2006
CHRISTOF KOLB, M.D., BERND WILLE, M.D.,
DOMINIK MAURER, M.D., ANDREAS SCHUCHERT, M.D., RALF WEBER, M.D., VOLKER
SCHIBGILLA, M.D., NORBERT KLEIN, M.D., ALEXANDER HÜMMER, CLAUS SCHMITT, M.D.,
and BERNHARD ZRENNER, M.D., on behalf of the FFS-Test Study Group
Background and Objective:
Far-field R wave sensing (FFS) in the atrial channel of dual chamber pacemakers
is a relevant source for inappropriate mode switch from the DDD mode to the DDI
or VDI mode. Inappropriate loss of atrioventricular synchrony due to false
positive mode switch is hemodynamically disadvantageous, may induce atrial
tachyarrhythmias, can lead to pacemaker syndrome, and impairs the reliability of
pacemaker Holter data. The aim of the study was to determine whether individual
adjustment of the postventricular atrial blanking period (PVAB) based on an
additional test is effective in avoiding inappropriate mode switch due to FFS
when compared with standard programming of the PVAB.
Methods: A total of 207 patients were supplied with a St. Jude Medical Identity
DR® or Identity ADx DR® dual chamber pacemaker for sinus nodal disease (n = 84),
atrioventricular block (n = 79), binodal disease (n = 35), or other indications
(n = 9). At hospital discharge, they were randomized to an individually
optimized PVAB (n = 100) or to a control group with the PVAB left at the nominal
of 100 msec (n = 107). Primary endpoint was the occurrence of inappropriate mode
switch due to FFS within 3 months after pacemaker implantation assessed by
stored electrograms of the pacemaker.
Results: At the 3-month follow-up, 28/107 (26%) patients with the standard
programming of the PVAB showed at least one episode of inappropriate mode switch
due to FFS versus 10/100 (10%) patients with optimized PVAB (P < 0.01). The
optimized PVAB was shorter than the nominal PVAB in about one-third of patients
and longer in about two-third of patients. Different atrial lead localizations
were not associated with the occurrence of inappropriate mode switch.
Conclusions: Individual adjustment of the PVAB significantly reduces the
incidence of inappropriate mode switch due to FFS.
Journal of Cardiovascular
Electrophysiology Volume 17 Page 944 - September 2006
RONG BAI, M.D., DIMPI PATEL, M.D., LUIGI
DI BIASE, M.D., TAMER S. FAHMY, M.D., MARKETA KOZELUHOVA, M.D., SUBRAMANYA
PRASAD, M.D., ROBERT SCHWEIKERT, M.D., JENNIFER CUMMINGS, M.D., WALID SALIBA,
M.D., MICHELLE ANDREWS-WILLIAMS, R.N., B.S.N., SAKIS THEMISTOCLAKIS, M.D., ALDO
BONSO, M.D., ANTONIO ROSSILLO, M.D., ANTONIO RAVIELE, M.D., CLAUS SCHMITT, M.D.,
MARTIN KARCH, M.D., JORGE A. SALERNO URIARTE, M.D., PATRICK TCHOU, M.D.,
MAURICIO ARRUDA, M.D., and ANDREA NATALE, M.D.
Introduction: Phrenic nerve
injury (PNI) is a complication that can occur with catheter ablation.
Methods: Data from 17 patients with PNI following different catheter ablation
techniques were reviewed. PNI was defined as decreased motility (transient) or
paralysis (persistent) of the hemi-diaphragm on fluoroscopy or chest X-ray.
Patient's recovery was monitored. Normalization of chest images and sniff test
would be considered as complete clinical recovery.
Results: Out of the 17 PNI patients (16 right, 1 left), 13 (11 persistent, 2
transient) occurred after pulmonary veins isolation with or without superior
vena cava ablation. Three patients had persistent PNI after sinus node
modification and one other patient experienced PNI after epicardial ventricular
tachycardia ablation. Ablation was performed with different energy source
including radiofrequency (n = 13), cryothermal (n = 1), ultrasound (n = 2) and
laser (n = 1). Patient's symptoms varied broadly from asymptomatic to dyspnea,
and even to respiratory insufficiency that required temporary mechanical
ventilation support. Two patients with transient PNI resolved immediately after
the procedure and the other 15 persistent PNI patients resolved within a mean
time of 8.3 ± 6.6 months.
Conclusions: PNI caused by catheter
ablation appears to functionally recover over time regardless of the energy
sources used for the procedure.
Circulation. 2006;114:591-596
Samuel V. Lichtenstein, MD, PhD; Anson
Cheung, MD; Jian Ye, MD; Christopher R. Thompson, MD; Ronald G. Carere, MD;
Sanjeevan Pasupati, MD; John G. Webb, MD
Background— Aortic valve
replacement with cardiopulmonary bypass is currently the treatment of choice for
symptomatic aortic stenosis but carries a significant risk of morbidity and
mortality, particularly in patients with comorbidities. Recently, percutaneous
transfemoral aortic valve implantation has been proposed as a viable alternative
in selected patients. We describe our experience with a new, minimally invasive,
catheter-based approach to aortic valve implantation via left ventricular apical
puncture without cardiopulmonary bypass or sternotomy.
Methods and Results— A left anterolateral intercostal incision is used to expose
the left ventricular apex. Direct needle puncture of the apex allows
introduction of a hemostatic sheath into the left ventricle. The valve
prosthesis, constructed from a stainless steel stent with an attached trileaflet
equine pericardial valve, is crimped onto a valvuloplasty balloon. The
prosthetic valve and balloon catheter are passed over a wire into the left
ventricle. Positioning within the aortic annulus is confirmed by fluoroscopy,
aortography, and echocardiography. Rapid ventricular pacing is used to reduce
cardiac output while the balloon is inflated, deploying the prosthesis within
the annulus. Transapical aortic valve implantation was successfully performed in
7 patients in whom surgical risk was deemed excessive because of comorbidities.
Echocardiographic median aortic valve area increased from 0.7±0.1 cm2 (interquartile
range) to 1.8±0.8 cm2 (interquartile range). There were no intraprocedural
deaths. At a follow up of 87±56 days, 6 of 7 patients remain alive and well.
Conclusions— This initial experience suggests that transapical aortic valve
implantation without cardiopulmonary bypass is feasible in selected patients
with aortic stenosis.
Eur Heart J 27: 1824-1832
Silvana Quaglini, Carla Rognoni, Carla
Spazzolini, Silvia G. Priori, Savina Mannarino and Peter J. Schwartz
Aims A significant number of
preventable cardiac deaths in infancy and childhood are due to long QT syndrome
(LQTS) and to unrecognized neonatal congenital heart diseases (CHDs). Both carry
a serious risk for avoidable mortality and morbidity but effective treatments
exist to prevent lethal arrhythmias or to allow early surgical correction before
death or irreversible cardiac damage. As an electrocardiogram (ECG) allows
recognition of LQTS and of some of the CHDs that have escaped medical diagnosis,
and as LQTS also contributes to sudden infant death syndrome, we have analysed
the cost-effectiveness of a nationwide programme of neonatal ECG screening. Our
primary analysis focused on LQTS alone; a secondary analysis focused on the
possibility of identifying some CHDs also.
Methods and results A decision analysis approach was used, building a decision
tree for the strategies ‘screening’–‘no screening’. Markov processes were used
to simulate the natural or clinical histories of the patients. To assess the
impact of potential errors in the estimates of the model parameters, a Monte
Carlo sensitivity analysis was performed by varying all baseline values by ±30%.
Incremental cost-effectiveness analysis for the primary analysis shows that with
the screening programme, the cost per year of life saved is very low: 11 740.
The cost for saving one entire life of 70 years would be 820 000. Even by
varying model parameters by ±30%, the cost per year of life saved remains
between 7400 and 20 400. These figures define ‘highly cost-effective’ screening
programmes. The secondary analysis provides even more cost-effective results.
Conclusion A programme of neonatal ECG screening performed in a large European
country is cost-effective. An ECG performed in the first month of life will
allow the early identification of still asymptomatic infants with LQTS and also
of infants with some correctable CHDs not recognized by routine neonatal
examinations. Appropriate therapy will prevent unnecessary deaths in infants,
children, and young adults.
New Engl J Med Volume 355:549-559
August 10, 2006
The Stroke Prevention by Aggressive
Reduction in Cholesterol Levels (SPARCL) Investigators
Background Statins reduce the
incidence of strokes among patients at increased risk for cardiovascular
disease; whether they reduce the risk of stroke after a recent stroke or
transient ischemic attack (TIA) remains to be established.
Methods We randomly assigned 4731 patients who had had a stroke or TIA within
one to six months before study entry, had low-density lipoprotein (LDL)
cholesterol levels of 100 to 190 mg per deciliter (2.6 to 4.9 mmol per liter),
and had no known coronary heart disease to double-blind treatment with 80 mg of
atorvastatin per day or placebo. The primary end point was a first nonfatal or
fatal stroke.
Results The mean LDL cholesterol level during the trial was 73 mg per deciliter
(1.9 mmol per liter) among patients receiving atorvastatin and 129 mg per
deciliter (3.3 mmol per liter) among patients receiving placebo. During a median
follow-up of 4.9 years, 265 patients (11.2 percent) receiving atorvastatin and
311 patients (13.1 percent) receiving placebo had a fatal or nonfatal stroke
(5-year absolute reduction in risk, 2.2 percent; adjusted hazard ratio, 0.84; 95
percent confidence interval, 0.71 to 0.99; P=0.03; unadjusted P=0.05). The
atorvastatin group had 218 ischemic strokes and 55 hemorrhagic strokes, whereas
the placebo group had 274 ischemic strokes and 33 hemorrhagic strokes. The
five-year absolute reduction in the risk of major cardiovascular events was 3.5
percent (hazard ratio, 0.80; 95 percent confidence interval, 0.69 to 0.92;
P=0.002). The overall mortality rate was similar, with 216 deaths in the
atorvastatin group and 211 deaths in the placebo group (P=0.98), as were the
rates of serious adverse events. Elevated liver enzyme values were more common
in patients taking atorvastatin.
Conclusions In patients with recent stroke or TIA and without known coronary
heart disease, 80 mg of atorvastatin per day reduced the overall incidence of
strokes and of cardiovascular events, despite a small increase in the incidence
of hemorrhagic stroke.
Europace 8: 416-420
Jalila Kihel1, Antoine Da Costa, Abdel
Kihel, Cécile Roméyer-Bouchard, Jérôme Thévenin, Régis Gonthier, Bernard Samuel
and Karl Isaaz
Aims The purpose of this
study was to evaluate the efficacy, risks, safety, and follow-up of
radiofrequency (RF) catheter ablation of atrioventricular nodal re-entrant
tachycardia (AVRNT) in patients (pts) 75 years old (n=42) (GpI) compared with
pts younger than 75 years (n=234) (GpII).
Methods and results The study population consisted of 276 consecutive pts (39.5%
men/60.5% women), from 15 to 98-year-old (average 56±17 years) with AVRNT
referred for RF ablation (RFA) from October 1997 to January 2004. Combined
anatomical and electrogram approaches were used to guide RFA. The cumulative
risk of AVRNT recurrence was analysed by the Kaplan–Meier method and log-rank
test. The average follow-up was 34±18 months. GpI (80±4 years) differed
significantly from GpII (51±14 years) regarding: heart rate tachycardia (160±20
vs. 180±30 bpm; P=0.0001), the slow pathway antegrade refractory period (370±70
vs. 340±60 ms; P=0.01), the fast pathway antegrade refractory period (360±60 vs.
330±60 ms; P=0.003), retrograde refractory period (360±60 vs. 330±60 ms;
P=0.0007), left ventricular ejection fraction (60±12 vs. 65±7%; P=0.0009), and
ischaemic ECG signs during tachycardia (76.2% vs. 61%; P=0.09). RFA was
successfully obtained in 275/276 (99.6%), 42/42 in GpI (100%), and 233/234
(99.6%) in GpII. Five complications occurred (1.8%): major complications in two
pts (0.7%) and minor complications in three pts (1.1%). Major complications were
deep venous thrombosis with pulmonary embolus (n=1) and pericardial effusion
(n=1), minor complications were groin haematoma (n=3). One complication was
observed in GpI (groin haematoma) (2.4%) and four in GpII (deep venous
thrombosis with pulmonary embolus in one, groin haematoma in two, and
pericardial effusion in one) (1.7%). The number of recurrences was not
statistically different between the two groups (0 vs. 3.4%; P=0.5) with a
respective average follow-up of 28±18 and 35±18 months, respectively.
Conclusion Catheter ablation of AVRNT in elderly and very elderly pts appears to
be a reasonable approach regarding feasibility and effectiveness without
increasing the risk of AV block.
PACE 2006; 29:759–764
WOLFRAM GRIMM, EVELINE PLACHTA, and
BERNHARD MAISCH
Aims: Antitachycardia pacing
(ATP) has not routinely been used in patients who received implantable
cardioverter defibrillators (ICDs) for primary prevention of sudden death. This
study investigated the efficacy of empirical ATP to terminate rapid ventricular
tachycardia (VT) in heart failure patients with prophylactic ICD therapy.
Methods and Results: Ninety-three patients with a mean left ventricular ejection
fraction of 22 ± 7% (range: 9–35%) due to nonischemic or ischemic cardiomyopathy
received prophylactic ICDs with empiric ATP. At least 2 ATP sequences with
6-pulse burst pacing trains at 81% of VT cycle length (CL) were programmed in
one or two VT zones for CL below 335 ± 23 ms and above 253 ± 18 ms. Ventricular
flutter and fibrillation (VF) with CL below 253 ± 18 ms were treated in a
separate VF zone with ICD shocks without preceding ATP attempts. During 38 ± 27
months follow-up, 339 spontaneous ventricular tachyarrhythmias occurred in 36 of
93 study patients (39%). A total of 232 VT episodes, mean CL 293 ± 22 ms,
triggered ATP in 25 of 36 patients with ICD interventions (69%). ATP terminated
199 of 232 VT episodes (86%) with a mean CL of 294 ± 23 ms in 23 of 25 patients
(88%) who received ATP therapy. ATP failed to terminate or accelerated 33 of 232
VT episodes (14%) with a mean CL of 287 ± 19 ms in 12 of 25 patients (48%) who
received ATP therapy.
Conclusions: Painfree termination of rapid VT with empirical ATP is common in
heart failure patients with prophylactic ICD therapy. The occasional inability
of empiric ATP to terminate rapid VT in almost 50% of patients who receive ATP
for rapid VT warrants restrictive ICD programming with regard to the number of
ATP attempts in order to avoid syncope before VT termination occurs.
Europace 8: 403-407
Jan Wilko Schrickel, Joerg O. Schwab,
Alexander Yang, Helga Bielik, Alexander Bitzen, Berndt Lüderitz and Thorsten
Lewalter
Aims Amiodarone is one of the
most efficient and safe antiarrhythmic drugs in the treatment of atrial
fibrillation (AF). Although pro-arrhythmic effects of amiodarone therapy are
rare, the aim of the present study was to identify clinical constellations which
may lead to amiodarone-associated pro-arrhythmia.
Methods and results Sixty-three consecutive patients (pts) (49 males; 64±10.3
years; 35 with coronary heart disease, 17 with lone AF) were retrospectively
included in this study. All received an oral (92.1%) or iv (7.9%) loading dose
of amiodarone for the treatment of AF. Cardiac diseases, concomitant medical
treatment, and incidence of pro-arrhythmic effects were analysed. Three pts
(4.8% of the total population) developed a clinical relevant, polymorphic
ventricular tachyarrhythmia, 3–48 h after initiation of amiodarone loading.
Coronary heart disease was present in all of these pts, and in two of them left
ventricular ejection fraction was severely reduced. The mean QTc in these pts
was only slightly prolonged; mean heart rate was significantly decreased
compared with the total study population (61.0±7.5 vs. 74.5±24.1 bpm; P 0.05).
In all pts with pro-arrhythmia, amiodarone (two pts iv, one patient oral) was
initiated during concomitant beta-blocker/digitalis therapy. Twenty-five per
cent of the patients receiving this ‘triple’ therapy developed ventricular
arrhythmia.
Conclusion The present study implies that initiation of amiodarone therapy in
pts with structural heart disease and AF that are concomitantly treated with
beta-blockers and digitalis may have an increased risk of amiodarone-associated
pro-arrhythmia.
Europace 8: 530-536
Massimo Stefano Silvetti, Fabrizio Drago,
Giorgia Grutter, Antonella De Santis, Vincenzo Di Ciommo and Lucilla Ravà
Aims The aim of this study
was to evaluate long-term outcome of pacemakers (PMs) in paediatric patients.
Methods and results Patients' data were retrospectively reviewed. We recorded
the techniques and systems used, any complication, and outcome. Endocardial
leads were inserted by transcutaneous puncture of subclavian vein and fixed with
a non-absorbable ligature, and epicardial leads by standard surgical technique.
Lead survival was calculated and plotted with the product limit method of
Kaplan–Meier. Between 1982 and 2002, 292 patients, aged 8±7 years (range 1
day–18 years), underwent PM implantation: the first PM had endocardial leads in
165 patients and epicardial in 127 patients. Structural heart disease (HD) was
present in 239 patients. Follow-up was 5±4 (range 0.1–18) years. There were no
pacing-related deaths. In total, 211 endocardial implantation procedures with 90
atrial and 165 ventricular leads and 145 epicardial procedures with 103 atrial
and 123 ventricular leads were performed. Early (<3 months) complications:
haemothorax occurred in 3.5% of endocardial leads and dislodgement was not
significantly different for atrial and ventricular endocardial leads. Late
complications: 63 leads failed (48 epicardial), with the worst outcome for
conventional epicardial leads (31 vs. 9% endocardial, P<0.05; steroid eluting 8%
epicardial vs. 5% endocardial, P=NS). Endocardial atrial leads failed (7%) in
operated HD and ventricular leads failed (6%) after body growth, without
difference in estimated mean survival time (11 years). Early and late PM
infection/erosion was 2% in all patients.
Conclusion Pacing in children shows good results, but complications are frequent
and related to leads. Endocardial pacing showed better long-term outcome.
Europace 8: 601-606
Rungroj Krittayaphong, Charn
Sriratanasathavorn, Chatkanok Dumavibhat, Sachana Pumprueg, Warangkana
Boonyapisit, Sukanya Pooranawattanakul, Suteera Phrudprisan and Charuwan
Kangkagate
Aims The objectives of this
study were to identify electrocardiographic (ECG) predictors of long-term
outcomes after radiofrequency (RF) ablation in patients with right-ventricular
outflow tract (RVOT) tachycardia.
Methods and results We correlated ECG characteristics with RF ablation outcomes
in 144 patients with RVOT tachycardia who underwent RF ablation for >1 year.
Unfavourable RF ablation outcomes were predefined as unsuccessful RF ablation or
recurrence of tachycardia requiring repeated ablation. RF ablation was not
successful in 11 (7.6%) patients and 16 (12%) patients had arrhythmia recurrence
requiring repeated ablation. Average follow-up time was 72.2±28.4 months.
Selected parameters from univariate analysis included number of RF applications,
pacemapping, application of bonus burn, procedure time, monophasic R-wave in
lead I, QS pattern in leads I and aVL, QRS duration in leads II and V2, and
right axis deviation, in ventricular tachycardia. From logistic regression
analysis, only monophasic R-wave in lead I remained in the final equation
(P=0.004, odds ratio 12.9).
Conclusion Monophasic R-wave in lead I
during RVOT tachycardia is associated with unfavourable outcomes after RF
ablation. This finding may help clinicians in the selection of patients
for RF ablation and for the prediction of RF ablation outcome.
Heart Rhythm Volume 3, Issue 7,
Pages 762-768 (July 2006)
Harikrishna Tandri, MD, Lawrence S.
Griffith, MD, Tania Tang, MD, Khurram Nasir, MD, Omeed Zardkoohi, MD,
Chandrasekhar Vasam Reddy, MD, Melissa Capps, RN, Hugh Calkins, MD, J. Kevin
Donahue, MD
Background
Implantable cardioverter-defibrillators (ICDs) are increasingly used for primary
and secondary prevention of sudden cardiac death. Defibrillators were introduced
into clinical practice in 1980. Since that time, factors affecting long-term
survival and the natural history of defibrillator patients have not been
described.
Objectives
The purpose of this study was to identify clinical predictors of long-term
survival in patients receiving ICDs.
Methods
The prognostic value of several clinical variables on the likelihood of survival
or appropriate ICD therapy in 1,382 consecutive patients receiving ICDs from
1980 to 2003 were evaluated. Data were collected at the time of device
implantation, and follow-up was completed through March 2005.
Results
In 70 ± 51 months of follow-up (range 0–282 months), 792 patients died and 421
patients received appropriate ICD therapy at least once. Age, left ventricular
ejection fraction, New York Heart Association (NYHA) functional class, Charlson
comorbidity index, and antiarrhythmic drug use correlated with mortality.
β-Blocker and angiotensin-converting enzyme inhibitor use was associated with
improved survival. Only NYHA functional class correlated with ICD therapy.
Patients free of shocks for the first 5 years after ICD implantation had
continued risk of arrhythmia recurrence.
Conclusion
The heart failure characteristics of
patients predicted ICD shock probability and survival better than the arrhythmia
characteristics or the underlying heart disease. Antiarrhythmic drug use
was associated with increased mortality. Beta-blocker and angiotensin-converting
enzyme inhibitor use was associated with improved survival. A measurable
arrhythmic risk even after prolonged shock-free intervals indicates the need for
continued ICD therapy in all patients with appropriate ICD indications.
Europace 8: 588-591
Z. Iakobishvili, J. Kusniec, R.
Shohat-Zabarsky, A. Mazur, A. Battler and B. Strasberg
Aim The occurrence of
accelerated junctional rhythm during radiofrequency energy delivery at the
region of the slow pathway is a well-recognized marker of successful treatment
of atrioventricular nodal re-entry tachycardia (AVNRT). Our aim was to evaluate
if the quantity and duration of accelerated junctional rhythm during
radiofrequency ablation of the slow pathway is correlated with residual slow
pathway conduction.
Methods and results Forty consecutive patients with AVNRT undergoing
radiofrequency ablation of slow pathway who developed accelerated junctional
rhythm during ablation were included. We compared accelerated junctional rhythm
quantity and duration between two groups: group A, without echo beats and group
B, with echo beats on post-ablation electrophysiology study. The total amount of
accelerated junctional rhythm was significantly greater in group A than in group
B [75.0 (63.5–165.0) vs. 36.0 (24.0–65.0), P=0.006], as well as total duration
of accelerated junctional rhythm [47.0(33.5–81.0) s vs. 23.0 (16.0–42.0) s,
P=0.006]. The cycle length of accelerated junctional rhythm did not differ
between the two groups [510.0 (445.0–545.0) ms vs. 500.0 (450.0–585.0) ms,
P=0.5).
Conclusions The amount and duration of accelerated junctional rhythm is
correlated with the total abolishment abolition of slow pathway conduction. A
higher amount and duration of accelerated junctional rhythm during
radiofrequency applications may be an additional marker of successful ablation.
Europace 8: 607-612
Matthias Paul, Michael Schäfers, Matthias
Grude, Florian Reinke, Kai Uwe Juergens, Roman Fischbach, Otmar Schober, Günter
Breithardt and Thomas Wichter
Aims We report three young
patients presenting with life-threatening ventricular tachycardia (VT) or
ventricular fibrillation (VF) and/or survived sudden cardiac arrest, who were
admitted to our institution for further diagnostic evaluation.
Methods and results In all patients, idiopathic left ventricular (LV) aneurysms
were identified after a detailed non-invasive and invasive evaluation. Sustained
VT/VF was inducible during programmed ventricular stimulation in two of the
three patients. Left ventricular aneurysms were depicted and characterized by
various imaging modalities (echocardiography, magnetic resonance imaging, LV
angiography). To elucidate the pathogenesis further, both myocardial viability
and regional sympathetic innervation were assessed by radionuclide imaging
techniques. Defects of innervation and metabolism were documented in the area of
the aneurysm but distal to the aneurysm there were no signs of downstream
denervation.
Conclusion Life-threatening arrhythmias
may be the first manifestation of an idiopathic LV aneurysm, which can be
reliably diagnosed with modern imaging techniques. Radionuclide imaging may
yield additional information as to the involvement of the autonomic nervous
system potentially associated with arrhythmogenesis. Management strategies in
patients with an idiopathic LV aneurysm range from antiarrhythmic drug
treatment, implantation of an automatic cardioverter–defibrillator to surgical
aneurysmectomy.
J Cardiovasc Electrophysiol, Vol.
17, pp. 602-607, June 2006
TAKANORI IKEDA, M.D., PH.D., F.A.C.C.,
ATSUKO ABE, M.D., SATORU YUSU, M.D., KENTARO NAKAMURA, M.D., HARUHISA ISHIGURO,
M.D., HISAAKI MERA, M.D., MASAYUKI YOTSUKURA, M.D., HIDEAKI YOSHINO, M.D.
Introduction: Autonomic
modulation, particularly high vagal tone, plays an important role in the
occurrence of ventricular tachyarrhythmias in the Brugada syndrome. Food intake
modulates vagal activity. We assessed the usefulness of a novel diagnostic
technique, the "full stomach test," for identifying a high-risk group in
patients with a Brugada-type electrocardiogram (ECG).
Methods and Results: In 35 patients with a Brugada-type ECG, we assessed 12-lead
ECGs before and after a large meal, a pilsicainide pharmacological test,
spontaneous ST-segment change, late potentials by signal-averaged ECG, microvolt
T-wave alternans, and four other ECG parameters. These patients were divided
into two groups (i.e., high-risk group [n = 17] and indeterminate risk group [n
= 18]). The full stomach test was defined as positive when augmentation of
characteristic ECG abnormalities was observed after meals. Thirteen patients had
a prior history of life-threatening events such as aborted sudden death and
syncope, with a total of 30 episodes. These episodes had a circadian pattern, at
night and after meals. The full stomach test was positive in 17 of the study
patients (49%). A positive test outcome was characterized by a higher incidence
of a history of life-threatening events than a negative test outcome (P = 0.015,
odds ratio = 7.1). In comparison between the two groups, the incidence (82%) of
positive outcomes in the high-risk group was significantly higher than that
(17%) in the indeterminate risk group (P = 0.0002).
Conclusions: Characteristic ECG changes diagnostic of Brugada syndrome are
augmented by a large meal. These data are associated with a history of
life-threatening events in Brugada syndrome.
Circulation 2006, Published
Online early
Stefan H. Hohnloser MD, Paul Dorian MD,
Robin Roberts MTech, Michael Gent MSc, Carsten W. Israel MD, Eric Fain MD, Jean
Champagne MD, and Stuart J. Connolly MD
Background--Many patients
with implanted cardioverter defibrillators (ICDs) receive adjunctive
antiarrhythmic drug therapy, most commonly amiodarone or sotalol. The effects of
these drugs on defibrillation energy requirements have not been previously
assessed in a randomized controlled trial.
Methods and Results--The Optimal Pharmacological Therapy in Cardioverter
Defibrillator Patients (OPTIC) trial was a randomized clinical trial evaluating
the efficacy of amiodarone plus -blocker and sotalol versus -blocker alone for
reduction of ICD shocks. Within OPTIC, a prospectively designed substudy
evaluated the effects of the 3 treatment arms on defibrillation energy
requirements. Defibrillation thresholds (DFTs) were measured (binary step-down
protocol) at baseline and again after 8 to 12 weeks of therapy in 94 patients,
of whom 29 were randomized to receive -blocker therapy (control group), 35 to
amiodarone plus -blocker, and 30 to sotalol. In the control group, the mean DFT
decreased from 8.77±5.15 J at baseline to 7.13±3.43 J (P=0.027); in the
amiodarone group, DFT increased from 8.53±4.29 to 9.82±5.84 J (P=0.091). In the
sotalol group, DFT decreased from 8.09±4.81 to 7.20±5.30 J (P=0.21). DFT changes
in the -blocker and the amiodarone group were significantly different (P=0.006).
In all patients, adequate safety margins for defibrillation were maintained. No
clinical variable predicted baseline DFT or changes in DFT on therapy.
Conclusion--Although amiodarone
increased DFT, the effect size with modern ICD systems is very small. Therefore,
DFT reassessment after the institution of antiarrhythmic drug therapy with
amiodarone or sotalol is not routinely required.
J Cardiovasc Electrophysiol, Vol.
17, pp. 586-593, June 2006
PHILIPPINE KIÈS, M.D., MARIANNE BOOTSMA,
M.D., PH.D., JEROEN J. BAX, M.D., PH.D., KATJA ZEPPENFELD, M.D., PH.D., LIESELOT
VAN ERVEN, M.D., PH.D., MAURITS C. WIJFFELS, M.D., PH.D., ERNST E. VAN DER WALL,
M.D., PH.D., and MARTIN J. SCHALIJ, M.D., PH.D.
Introduction: Diagnosis of
arrhythmogenic right ventricular dysplasia/cardiomyopathy (ARVD/C) is based on a
set of criteria proposed by the International Task Force (TF) for
Cardiomyopathies in 1994. To fulfill these criteria, presence of both
electrocardiographic and anatomical abnormalities must be assessed with ECG and
imaging techniques, respectively. This may be difficult in patients with
early/mild forms of the disease as detectable structural abnormalities may still
be absent. We evaluated in which patients presenting with right ventricular
tachycardia (VT) serial reevaluation for ARVD/C is indicated.
Methods and Results: Sixty consecutive patients (41 men, mean age 40±15 years)
were evaluated by the TF criteria for possible ARVD/C because of presentation
with a left bundle branch block (LBBB) VT, representing 1 minor criterion. The
presence on the ECG of a T-wave inversion beyond lead V2 (1 minor), right
precordial QRS prolongation (1 major), or an epsilon wave (1 major) was assessed
together with the visualization of severe regional/global right ventricle
dysfunction (1 major) or mild segmental dilatation/regional hypokinesia (1
minor) by standard imaging techniques. Initially, 22 (37%) patients were
diagnosed as having ARVD/C. After 47±39 (range 6–146) months, 23 initially TF-negative
patients were reevaluated because of recurrent symptoms, with 12 (52%)
additional patients now meeting the TF criteria. Eleven of these 12 (92%)
patients presented initially with ECG abnormalities only, but developed
structural abnormalities on imaging at follow-up.
Conclusion: ECG abnormalities may precede structural abnormalities warranting
serial reevaluation for ARVD/C in initially TF-negative patients presenting with
LBBB VT with only ECG abnormalities.
J Cardiovasc Electrophysiol, Vol.
17, pp. 754-759, July 2006
YANIV BAR-COHEN, M.D., CHARLES I. BERUL,
M.D., MARK E. ALEXANDER, M.D., ELIZABETH B. FORTESCUE, M.D., EDWARD P. WALSH,
M.D., JOHN K. TRIEDMAN, M.D., and FRANK CECCHIN, M.D.
Background: Venous occlusion
is a recognized complication of transvenous pacing, and lead cross-sectional
area indexed to body surface area (BSA) has been used to predict venous
obstruction in children.
Objective: The aim of this study was to identify the risk factors and incidence
of angiographic venous obstruction after transvenous lead implantation in both
children and young adults.
Methods: Contrast venography was obtained in 85 of 90 consecutive patients
undergoing repeat pacemaker or ICD procedures from 2002 to 2004 at a single
cardiac center. Venograms were graded as complete venous obstruction,
significant partial obstruction (>70% with collaterals), or patent.
Results: The cohort had a median age of 15.0 years at implant and was divided
into two age groups: 3–12 years (n = 35) and 13 years and over (n = 50). After a
median interval of 6.5 years, complete obstruction was seen in 11 of 85 patients
(13%) and partial obstruction in another 10 patients (12%). No significant
differences were seen in the incidence of obstruction between the two age groups
although younger patients had a larger lead indexed to BSA ratio (6.82 vs 5.05,
P = 0.005). There were no significant differences between obstructed and
nonobstructed patients in relation to age, size, growth, or lead factors.
Conclusion: Transvenous lead systems
implanted in young children have a similar incidence of venous occlusion
compared to older patients. Furthermore, patient age, body size, and lead
characteristics at implant do not clearly predict venous occlusion.
Circulation 2006, Published early
online
Daniel B. Mark MD, MPH*, Charlotte L.
Nelson MS, Kevin J. Anstrom PhD, Sana M. Al-Khatib MD, Anastasios A. Tsiatis
PhD, Patricia A. Cowper PhD, Nancy E. Clapp-Channing RN, MPH, Linda Davidson-Ray
MA, Jeanne E. Poole MD, George Johnson BSEE, Jill Anderson RN, Kerry L. Lee PhD,
Gust H. Bardy MD, for the SCD-HeFT Investigators
Background--In the Sudden
Cardiac Death in Heart Failure Trial (SCD-HeFT), implantable
cardioverter-defibrillator (ICD) therapy significantly reduced all-cause
mortality rates compared with medical therapy alone in patients with stable,
moderately symptomatic heart failure, whereas amiodarone had no benefit on
mortality rates. We examined long-term economic implications of these results.
Methods and Results--Medical costs were estimated by using hospital billing data
and the Medicare Fee Schedule. Our base case cost-effectiveness analysis used
empirical clinical and cost data to estimate the lifetime incremental cost of
saving an extra life-year with ICD therapy relative to medical therapy alone. At
5 years, the amiodarone arm had a survival rate equivalent to that of the
placebo arm and higher costs than the placebo arm.
For ICD relative to medical therapy
alone, the base case lifetime cost-effectiveness and cost-utility ratios
(discounted at 3%) were $38 389 per life-year saved (LYS) and $41 530 per
quality-adjusted LYS, respectively. A cost-effectiveness ratio <$100 000
was obtained in 99% of 1000 bootstrap repetitions. The cost-effectiveness ratio
was sensitive to the amount of extrapolation beyond the empirical 5-year trial
data: $127 503 per LYS at 5 years, $88 657 per LYS at 8 years, and $58 510 per
LYS at 12 years. Because of a significant interaction between ICD treatment and
New York Heart Association class, the cost-effectiveness ratio was $29 872 per
LYS for class II, whereas there was incremental cost but no incremental benefit
in class III.
Conclusions--Prophylactic use of single-lead, shock-only ICD therapy is
economically attractive in patients with stable, moderately symptomatic heart
failure with an ejection fraction 35%, particularly those in NYHA class II, as
long as the benefits of ICD therapy observed in the SCD-HeFT persist for at
least 8 years.
Circulation 2006, Published early
online
William H. Sauer MD, Concepcion Alonso MD,
Erica Zado PA-C, Joshua M. Cooper MD, David Lin MD, Sanjay Dixit MD, Andrea
Russo MD, Ralph Verdino MD, Sen Ji MD, Edward P. Gerstenfeld MD, David J.
Callans MD, and Francis E. Marchlinski MD
Background--Although the most
common sites of atrial ectopy that trigger atrial fibrillation (AF) are in or
around the pulmonary veins (PVs), atrioventricular nodal reentrant tachycardia
(AVNRT) can also cause or coexist with AF. We sought to characterize patients
with AF and AVNRT and assess clinical outcomes after ablation.
Methods and Results--To determine the prevalence of concomitant AVNRT and AF,
629 consecutive patients referred for catheter ablation between November 1998
and March 2005 were studied. Electrophysiological studies with programmed
stimulation during isoproterenol infusion identified atrial ectopy that
initiated AF and the presence of inducible AVNRT. AF ablation consisted of
proximal isolation of PVs and elimination of any non-PV trigger of AF, including
AVNRT. There were 27 patients (4.3%) who had inducible AVNRT at the time of AF
ablation. Of these, 13 underwent AVNRT ablation without PV isolation. Compared
with the rest of the cohort, patients with AVNRT and AF were younger at the time
of symptom onset (age 36.8±13.8 versus 48.2±11.7 years; P<0.01). Freedom from AF
with or without previously ineffective antiarrhythmic medication was similar in
both groups (96.3% versus 90.7%; mean follow-up 21.4±9.4 months); however,
patients with AVNRT targeted for ablation were more likely to be AF free while
not taking any antiarrhythmic medication after a single procedure during the
follow-up period (87.5% versus 54.7%; P<0.01) and had fewer complications (0%
versus 2.5%; P=0.30). Twelve of the 13
patients who underwent slow-pathway ablation without left atrial ablation
remained AF free without the need for antiarrhythmic medication after a single
procedure.
Conclusions--AVNRT is an uncommon AF trigger seen more frequently in younger
patients. Ablation of AVNRT in patients with AF was associated with improved
outcomes compared with those with other triggers of AF.
Circulation. 2006;114:I-1 – I-4
Jari Halonen, MD; Tapio Hakala, MD, PhD;
Tommi Auvinen, MD; Jari Karjalainen, MD, PhD; Anu Turpeinen, MD, PhD; Ari Uusaro,
MD, PhD; Pirjo Halonen, PhD; Juha Hartikainen, MD, PhD; Mikko Hippeläinen, MD,
PhD
Background— Atrial
fibrillation (AF) is the most common arrhythmia to occur after cardiac surgery,
with an incidence of 20% to 40%. AF is associated with postoperative
complications, including increased risk of stroke and need of additional
treatment, as well as prolonged hospital stay and increased costs. It has been
shown that prophylactic oral administration of ß-blocker therapy reduces the
incidence of postoperative AF after cardiac surgery. However, it is possible
that absorption of drugs is impaired after cardiopulmonary perfusion associated
with cardiac surgery. The purpose of this prospective, controlled, randomized
trial was to study compare intravenous and per oral metoprolol administration in
the prevention of AF after cardiac surgery.
Methods and Results— 240 consecutive patients who were scheduled to undergo
their first on-pump coronary artery bypass graft (CABG), aortic valve
replacement, or combined aortic valve replacement and CABG were randomized to
receive 48-hour infusion of metoprolol or oral metoprolol starting on the first
postoperative morning. Patients were excluded if they had contraindications for
ß-blocker or had to stay >1 day in the intensive care unit. Dosage of metoprolol
was adjusted according to heart rate. The dosage was 1 to 3 mg/h in the
intravenous group and from 25 mg twice per day to 50 mg 3 times per day in the
oral group. The incidence of postoperative AF was significantly lower in the
intravenous group than in the oral group (16.8% versus 28.1%, P=0.036). No
serious adverse effects were associated with intravenous metoprolol therapy.
Conclusions— Our study suggests that intravenous metoprolol is well-tolerated
and more effective than oral metoprolol in the prevention of AF after cardiac
surgery.
J Cardiovasc Electrophysiol, Vol.
17, pp. 741-746, July 2006
ATUL VERMA, M.D., FETHI KILICASLAN, M.D.,
JAMES R. ADAMS, M.D., STEVEN HAO, M.D., SALWA BEHEIRY, R.N., STEPHEN MINOR,
M.D., VOLKAN OZDURAN, M.D., SAMY CLAUDE ELAYI, M.D., DAVID O. MARTIN, M.D.,
ROBERT A. SCHWEIKERT, M.D., WALID SALIBA, M.D., JAMES D. THOMAS, M.D., MARIO
GARCIA, M.D., ALLAN KLEIN, M.D., and ANDREA NATALE, M.D.
Background: Although
pulmonary vein antrum isolation (PVAI) may cure atrial fibrillation (AF) and
improve left atrial (LA) function, the effect of extensive LA ablation on LA
function is not well known.
Objective: To assess the impact of PVAI on LA function remotely postablation.
Methods: Consecutive patients undergoing PVAI had either transthoracic (TTE) and
transesophageal (TEE) echocardiography (n = 41) or cine EBCT (n = 26) performed
preablation and 6 months postablation. Only patients with paroxysmal and
persistent, but not permanent, AF were included. Imaging was done in sinus
rhythm for all patients. LA diameter (LAD), LA systolic and diastolic areas, and
left atrial fractional area change (LFAC) were assessed by TTE. Transmitral (TMF),
left atrial appendage (LAA), and pulmonary venous (PVF) Doppler flows were
measured by TEE. Peak A on TMF, LAA peak emptying velocity (LAAF), and peak A
reversal (AR) on PVF were used as surrogates of LA contractile function. Peak S
on PV flow was used as a surrogate of reservoir function. LA areas, volumes, and
LA ejection fraction (LAEF) were measured from cine EBCT.
Results: Mean radiofrequency ablation time was 45 ± 21 minutes. All four PVs
were isolated for all patients; there were no cases of PV stenosis.
Echocardiography revealed a significant reduction in LAD and LA areas post-PVAI.
Both peak A and peak AR were also higher post, while other variables showed
strong trends toward improvement. In the subset of patients with persistent AF,
post-PVAI improvements were seen in LA size, peak A, and even peak S (P = 0.04).
Cine EBCT showed a significant decrease in both LA areas and volumes post-PVAI.
There was also a significant improvement in LAEF post-PVAI from 17 ± 6% to 22 ±
5% (P = 0.01).
Conclusion: Extensive ablation during PVAI does not cause deterioration in LA
function, and may cause long-term improvement, especially in patients with
higher AF burden.
J Cardiovasc Electrophysiol, Vol.
17, pp. 577-583, June 2006
ANIL K. GEHI, M.D., TRUONG D. DUONG, M.D.,
LOUISE D. METZ, M.D., J. ANTHONY GOMES, M.D., and DAVENDRA MEHTA, M.D., PH.D.
Background: The Brugada
syndrome is an increasingly recognized cause of idiopathic ventricular
fibrillation; however, there is wide variation in the prognosis of patients with
the Brugada ECG.
Methods and Results: We retrieved 30 prospective studies of patients with the
Brugada ECG, accumulating data on 1,545 patients. Summary estimates of the
relative risk (RR) of events (sudden cardiac death [SCD], syncope, or internal
defibrillator shock) for a variety of potential predictors were made using a
random-effects model. The overall event rate at an average of 32 months
follow-up was 10.0% (95% CI 8.5%, 11.5%). The RR of an event was increased (P <
0.001) among patients with a history of syncope or SCD (RR 3.24 [95% CI 2.13,
4.93]), men compared with women (RR 3.47 [95% CI 1.58, 7.63]), and patients with
a spontaneous compared with sodium-channel blocker induced Type I Brugada ECG
(RR 4.65 [95% CI 2.25, 9.58]). The RR of events was not significantly increased
in patients with a family history of SCD (P = 0.97) or a mutation of the SCN5A
gene (P = 0.18). The RR of events was also not significantly increased in
patients inducible compared with noninducible by electrophysiologic study (EPS)
(RR 1.88 [95% CI 0.62, 5.73], P = 0.27); however, there was significant
heterogeneity of the studies included.
Conclusions: Our findings suggest that a history of syncope or SCD, the presence
of a spontaneous Type I Brugada ECG, and male gender predict a more malignant
natural history. Our findings do not support the use of a family history of SCD,
the presence of an SCN5A gene mutation, or EPS to guide the management of
patients with a Brugada ECG.
J Am Coll Cardiol 47: 2477-2482
Alan Kadish, MD, Andi Schaechter, RN,
Haris Subacius, MA, Emil Thattassery, MD, William Sanders, MD, Kelley P.
Anderson, MD, Alan Dyer, PhD, Jeffrey Goldberger, MD and Joseph Levine, MD
OBJECTIVES: This study sought
to determine whether the time from diagnosis to randomization was related to
outcome in a clinical trial of implantable cardioverter-defibrillator (ICD)
insertion in nonischemic cardiomyopathy.
BACKGROUND: Whether the duration of nonischemic cardiomyopathy is related to
arrhythmic risk and the possible benefit of ICD insertion is unknown.
METHODS: The Defibrillators in Nonischemic Cardiomyopathy Treatment Evaluation
(DEFINITE) trial randomized 458 patients with nonischemic dilated cardiomyopathy
and a left ventricular ejection fraction <36% to receive standard medical
therapy with or without an ICD. Patients were randomized regardless of the
duration of known cardiomyopathy as long as a reversible cause of left
ventricular dysfunction was not present. Patients were divided into recently and
remotely diagnosed nonischemic cardiomyopathy groups based on the time from
diagnosis of cardiomyopathy to randomization. To categorize patients, cut points
of three and nine months were used.
RESULTS: Patients with recently diagnosed cardiomyopathy who received an ICD had
better survival than those treated with standard therapy at both cut points.
This difference in survival was significant at three months (p < 0.05) and was
borderline significant at nine months (p = 0.058). Patients with remotely
diagnosed cardiomyopathy did not have a significant survival benefit with ICD
insertion, but there were no significant differences between ICD benefit in the
recent and remote diagnosis groups (p = 0.17 and 0.25).
CONCLUSIONS: Patients who have a recent cardiomyopathy diagnosis do not have any
less ICD benefit than those with a remote diagnosis. Thus, ICD therapy should be
considered in such patients as soon as they are identified as long as a
reversible cause of left ventricular dysfunction is excluded.
Circulation. 2006;114:104-109
Stefan H. Hohnloser, MD; Paul Dorian, MD;
Robin Roberts, MTech; Michael Gent, MSc; Carsten W. Israel, MD; Eric Fain, MD;
Jean Champagne, MD; Stuart J. Connolly, MD
Background— Many patients
with implanted cardioverter defibrillators (ICDs) receive adjunctive
antiarrhythmic drug therapy, most commonly amiodarone or sotalol. The effects of
these drugs on defibrillation energy requirements have not been previously
assessed in a randomized controlled trial.
Methods and Results— The Optimal Pharmacological Therapy in Cardioverter
Defibrillator Patients (OPTIC) trial was a randomized clinical trial evaluating
the efficacy of amiodarone plus ß-blocker and sotalol versus ß-blocker alone for
reduction of ICD shocks. Within OPTIC, a prospectively designed substudy
evaluated the effects of the 3 treatment arms on defibrillation energy
requirements. Defibrillation thresholds (DFTs) were measured (binary step-down
protocol) at baseline and again after 8 to 12 weeks of therapy in 94 patients,
of whom 29 were randomized to receive ß-blocker therapy (control group), 35 to
amiodarone plus ß-blocker, and 30 to sotalol. In the control group, the mean DFT
decreased from 8.77±5.15 J at baseline to 7.13±3.43 J (P=0.027); in the
amiodarone group, DFT increased from 8.53±4.29 to 9.82±5.84 J (P=0.091). In the
sotalol group, DFT decreased from 8.09±4.81 to 7.20±5.30 J (P=0.21). DFT changes
in the ß-blocker and the amiodarone group were significantly different
(P=0.006). In all patients, adequate safety margins for defibrillation were
maintained. No clinical variable predicted baseline DFT or changes in DFT on
therapy.
Conclusion— Although amiodarone increased DFT, the effect size with modern ICD
systems is very small. Therefore, DFT reassessment after the institution of
antiarrhythmic drug therapy with amiodarone or sotalol is not routinely
required.
Circulation. 2006;114:135-142
Daniel B. Mark, MD, MPH; Charlotte L.
Nelson, MS; Kevin J. Anstrom, PhD; Sana M. Al-Khatib, MD; Anastasios A. Tsiatis,
PhD; Patricia A. Cowper, PhD; Nancy E. Clapp-Channing, RN, MPH; Linda
Davidson-Ray, MA; Jeanne E. Poole, MD; George Johnson, BSEE; Jill Anderson, RN;
Kerry L. Lee, PhD; Gust H. Bardy, MD, for the SCD-HeFT Investigators
Background— In the Sudden
Cardiac Death in Heart Failure Trial (SCD-HeFT), implantable
cardioverter-defibrillator (ICD) therapy significantly reduced all-cause
mortality rates compared with medical therapy alone in patients with stable,
moderately symptomatic heart failure, whereas amiodarone had no benefit on
mortality rates. We examined long-term economic implications of these results.
Methods and Results— Medical costs were estimated by using hospital billing data
and the Medicare Fee Schedule. Our base case cost-effectiveness analysis used
empirical clinical and cost data to estimate the lifetime incremental cost of
saving an extra life-year with ICD therapy relative to medical therapy alone. At
5 years, the amiodarone arm had a survival rate equivalent to that of the
placebo arm and higher costs than the placebo arm. For ICD relative to medical
therapy alone, the base case lifetime cost-effectiveness and cost-utility ratios
(discounted at 3%) were $38 389 per life-year saved (LYS) and $41 530 per
quality-adjusted LYS, respectively. A cost-effectiveness ratio <$100 000 was
obtained in 99% of 1000 bootstrap repetitions. The cost-effectiveness ratio was
sensitive to the amount of extrapolation beyond the empirical 5-year trial data:
$127 503 per LYS at 5 years, $88 657 per LYS at 8 years, and $58 510 per LYS at
12 years. Because of a significant interaction between ICD treatment and New
York Heart Association class, the cost-effectiveness ratio was $29 872 per LYS
for class II, whereas there was incremental cost but no incremental benefit in
class III.
Conclusions— Prophylactic use of single-lead, shock-only ICD therapy is
economically attractive in patients with stable, moderately symptomatic heart
failure with an ejection fraction 35%, particularly those in NYHA class II, as
long as the benefits of ICD therapy observed in the SCD-HeFT persist for at
least 8 years.
Re-examining the efficacy of ß-blockers for the treatment of hypertension: a
meta-analysis
CMAJ • June 6, 2006; 174 (12)
Nadia Khan and Finlay A. McAlister
Background: In a recently
published meta-analysis, investigators asserted that ß-blockers should not be
used to treat hypertension. Because the pathophysiology of hypertension differs
in older and younger patients, we designed this meta-analysis to clarify the
efficacy of ß-blockers in different age groups. The primary outcome was a
composite of stroke, myocardial infarction and death.
Methods: We identified randomized controlled trials that evaluated the efficacy
of ß-blockers as first-line therapy for hypertension in preventing major
cardiovascular outcomes. Both authors independently evaluated the eligibility of
all trials. Trials enrolling older (mean age at baseline 60 years) patients were
separated from those enrolling younger (mean age < 60 years) patients. Data were
pooled using a random effects model.
Results: Our analysis incorporated data from 145 811 participants in 21
hypertension trials. In placebo-controlled trials, ß-blockers reduced major
cardiovascular outcomes in younger patients (risk ratio [RR] 0.86, 95%
confidence interval [CI] 0.74–0.99, based on 794 events in 19 414 patients) but
not in older patients (RR 0.89, 95% CI 0.75–1.05, based on 1115 events in 8019
patients). In active comparator trials, ß-blockers demonstrated similar efficacy
to other antihypertensive agents in younger patients (1515 events in 30 412
patients, RR 0.97, 95% CI 0.88–1.07) but not in older patients (7405 events in
79 775 patients, RR 1.06, 95% CI 1.01–1.10), with the excess risk being
particularly marked for strokes (RR 1.18, 95% CI 1.07–1.30).
Interpretation: ß-blockers should not be considered first-line therapy for older
hypertensive patients without another indication for these agents; however, in
younger patients ß-blockers are associated with a significant reduction in
cardiovascular morbidity and mortality.
Biventricular Versus Conventional Right Ventricular Stimulation for Patients
With Standard Pacing Indication and Left Ventricular Dysfunction The Homburg
Biventricular Pacing Evaluation (HOBIPACE)
Journal of the American College
of Cardiology Volume 47, Issue 10 , 16 May 2006, Pages 1927-1937
Michael Kindermann MD, Benno Hennen MD,
Jens Jung MD, Jürgen Geisel MD, Michael Böhm MD and Gerd Fröhlig MD
Objectives
The Homburg Biventricular Pacing Evaluation (HOBIPACE) is the first randomized
controlled study that compares the biventricular (BV) pacing approach with
conventional right ventricular (RV) pacing in patients with left ventricular
(LV) dysfunction and a standard indication for antibradycardia pacing in the
ventricle.
Background
In patients with LV dysfunction and atrioventricular block, conventional RV
pacing may yield a detrimental effect on LV function.
Methods
Thirty patients with standard indication for permanent ventricular pacing and LV
dysfunction defined by an LV end-diastolic diameter ≥60 mm and an ejection
fraction ≤40% were included. Using a prospective, randomized crossover design,
three months of RV pacing were compared with three months of BV pacing with
regard to LV function, N-terminal pro-B-type natriuretic peptide (NT-proBNP)
serum concentration, exercise capacity, and quality of life.
Results
When compared with RV pacing, BV stimulation reduced LV end-diastolic (−9.0%, p
= 0.022) and end-systolic volumes (−16.9%, p < 0.001), NT-proBNP level (−31.0%,
p < 0.002), and the Minnesota Living with Heart Failure score (−18.9%, p =
0.01). Left ventricular ejection fraction (+22.1%), peak oxygen consumption
(+12.0%), oxygen uptake at the ventilatory threshold (+12.5%), and peak
circulatory power (+21.0%) were higher (p < 0.0002) with BV pacing. The benefit
of BV over RV pacing was similar for patients with (n = 9) and without (n = 21)
atrial fibrillation. Right ventricular function was not affected by BV pacing.
Conclusions
In patients with LV dysfunction who need permanent ventricular pacing support,
BV stimulation is superior to conventional RV pacing with regard to LV function,
quality of life, and maximal as well as submaximal exercise capacity.
Spironolactone Treatment and Clinical Outcomes in Patients With Systolic
Dysfunction and Mild Heart Failure Symptoms: A Retrospective Analysis
Journal of Cardiac Failure Volume
12, Issue 4 , May 2006, Pages 250-256
Ragavendra R. Baliga MD, Prathiba Ranganna
MD, Bertram Pitt MD and Todd M. Koelling MD
Background
The effect of spironolactone on clinical outcomes in patients with mild heart
failure is unclear.
Methods and Results
We performed a retrospective analysis of 482 consecutive patients with left
ventricular ejection fraction ≤40% and New York Heart Association I-II symptoms.
Major cardiac event (MCE) was defined as death, left ventricular assist device
implantation, or United Network of Organ Sharing 1 cardiac transplantation.
Proportional hazards analysis was used to determine predictors of MCE and to
derive an adjusted hazard for spironolactone therapy. Spironolactone was
prescribed to 279 (58%) patients and mean follow-up was 1029 days. After
controlling for predictors of clinical events, spironolactone treatment was
associated with a trend for lower risk of MCE or heart failure rehospitalization
(HR, 0.68; 95% CI, 0.43–1.07; P = .095). Exploration of interaction terms
between medications revealed that treatment with the combination of
spironolactone and thiazide diuretics was associated with lower risk of clinical
events (HR, 0.32; 95% CI, 0.12–0.89; P = .029).
Conclusion
In subjects with mild heart failure
treated with a thiazide diuretic, the use of spironolactone is associated with
reduced risk of MCE or heart failure
rehospitalization. A randomized controlled trial is necessary to
accurately define the clinical effects of spironolactone in patients with mild
heart failure.
Cardiovascular Outcomes With Atrial-Based Pacing Compared With Ventricular
Pacing. Meta-Analysis of Randomized Trials, Using Individual Patient Data
Published online Circulation 2006
before print June 26, 2006
Jeffrey S. Healey MD, MSc, William D. Toff
MD, Gervasio A. Lamas MD, Henning R. Andersen MD, Kevin E. Thorpe MMath, Kenneth
A. Ellenbogen MD, Kerry L. Lee PhD, Allan M. Skene PhD, Eleanor B. Schron MS, J.
Douglas Skehan MBBS, Lee Goldman MD, MPH, Robin S. Roberts MTech, A. John Camm
MD, Salim Yusuf MD, DPhil, and Stuart J. Connolly MD
Background--Several
randomized trials have compared atrial-based (dual-chamber or atrial) pacing
with ventricular pacing in patients with bradycardia. No trial has shown a
mortality reduction, and only 1 small trial suggested a reduction in stroke. The
goal of this review was to determine whether atrial-based pacing prevents major
cardiovascular events.
Methods and Results--A systematic review was performed of publications since
1980. For inclusion, trials had to compare an atrial-based with a
ventricular-based pacing mode; use a randomized, controlled, parallel design;
and have data on mortality, stroke, heart failure, or atrial fibrillation.
Individual patient data were obtained from 5 of the 8 identified studies,
representing 95% of patients in the 8 trials, and a total of 35 000
patient-years of follow-up. There was no significant heterogeneity among the
results of the individual trials. There was no significant reduction in
mortality (hazard ratio [HR], 0.95; 95% confidence interval [CI], 0.87 to 1.03;
P=0.19) or heart failure (HR, 0.89; 95% CI, 0.77 to 1.03; P=0.15) with
atrial-based pacing. There was a significant reduction in atrial fibrillation
(HR, 0.80; 95% CI, 0.72 to 0.89; P=0.00003) and a reduction in stroke that was
of borderline significance (HR, 0.81; 95% CI, 0.67 to 0.99; P=0.035). There was
no convincing evidence that any patient subgroup received special benefit from
atrial-based pacing.
Conclusions--Compared with ventricular pacing,
the use of atrial-based pacing does not
improve survival or reduce heart failure or cardiovascular death.
However, atrial-based pacing reduces the
incidence of atrial fibrillation and may modestly reduce stroke.
Radiofrequency ablation of arrhythmias guided by non-fluoroscopic catheter
location: a prospective randomized trial
Eur Heart J 27: 1223-1229
Mark J. Earley, Refai Showkathali, Maysaa
Alzetani, Peter M. Kistler, Dhiraj Gupta, Dominic J. Abrams, Julie A. Horrocks,
Stuart J. Harris, Simon C. Sporton, and Richard J. Schilling
Aims To compare the utility
of non-fluoroscopic mapping systems (Carto and Ensite NavX) with that of
conventional mapping in patients referred for catheter ablation of a wide
variety of arrhythmias.
Methods and results Patients referred for catheter ablation (excluding atrial
fibrillation, atypical atrial flutter, ventricular tachycardia in structural
heart disease, and complete AV nodal ablation) were randomized equally to a
procedure guided by Carto, Ensite NavX, or conventional mapping. A total of 145
patients were recruited (82 men, aged 49±16, range 18–85). In 19 patients, no
ablation was performed, and in the remaining, typical atrial flutter,
atrioventricular nodal re-entrant tachycardia, and atrioventricular re-entrant
tachycardias [including Wolff–Parkinson–White (WPW)] accounted for 93% of
ablations. Overall procedure time, immediate and short-term success,
complication rate, and freedom from symptoms at follow-up were identical for all
groups. NavX led to the least X-ray exposure: Navx vs. conventional, median
(range): 4 (0–50) vs. 13 (2–46) min (P<0.001); NavX vs. Carto, median (range): 4
(0–50) vs. 6 (1–55) min (P=0.008). Both Carto and NavX increased disposable
costs by 50% when compared with conventional (P<0.001). For typical atrial
flutter, Carto and NavX reduced screening times without increasing procedure
cost. If ablation was not performed, NavX was twice as expensive as Carto or
conventional.
Conclusion Ensite NavX and Carto procedures have similar effectiveness and
safety to a conventional approach; however, they both reduce X-ray exposure,
with NavX producing a significantly greater effect than Carto. Although this
benefit is achieved at a greater financial cost, there may be long-term benefits
to catheter laboratory staff.
Renal Function and Effectiveness of Angiotensin-Converting Enzyme Inhibitor
Therapy in Patients With Chronic Stable Coronary Disease in the Prevention of
Events with ACE inhibition (PEACE) Trial
Published online Circulation
before print June 26, 2006
Scott D. Solomon MD, Madeline M. Rice PhD,
Kathleen A. Jablonski PhD, Powell Jose BS, Michael Domanski MD, Marc Sabatine
MD, Bernard J. Gersh MD, ChB, DPhil, Jean Rouleau MD, Marc A. Pfeffer MD, PhD,
Eugene Braunwald MD, for the Prevention of Events with ACE inhibition (PEACE)
Investigators
Background--Patients with
reduced renal function are at increased risk for adverse cardiovascular
outcomes. In the post-myocardial infarction setting, angiotensin-converting
enzyme (ACE) inhibitors have been shown to be as effective in patients with
impaired renal function as in those with preserved renal function.
Methods and Results--We assessed the relation between renal function and
outcomes, the influence of ACE inhibition on this relation, and whether renal
function modifies the effectiveness of ACE inhibition in patients with stable
coronary artery disease and preserved systolic function enrolled in the
Prevention of Events with ACE inhibition trial (PEACE). Patients (n=8290) were
randomly assigned to receive trandolapril (target, 4 mg/d) or placebo. Clinical
creatinine measures were available for 8280 patients before randomization. The
estimated glomerular filtration rate (eGFR) was calculated with the 4-point
Modification of Diet in Renal Disease equation. Renal function was related to
outcomes, and the influence of ACE-inhibitor therapy was assessed with formal
interaction modeling. The mean eGFR in PEACE was 77.6±19.4, and 1355 (16.3%)
patients had reduced renal function (eGFR <60 mg • mL-1 • 1.73 m-2). We observed
a significant interaction between eGFR and treatment group with respect to
cardiovascular and all-cause mortality (P=0.02). Trandolapril was associated
with a reduction in total mortality in patients with reduced renal function
(adjusted HR, 0.73; 95% CI, 0.54 to 1.00) but not in patients with preserved
renal function (adjusted HR, 0.94; 95% CI, 0.78 to 1.13).
Conclusions--Although trandolapril did not improve survival in the overall PEACE
cohort, in which mean eGFR was relatively high, trandolapril reduced mortality
in patients with reduced eGFR. These data suggest that reduced renal function
may define a subset of patients most likely to benefit from ACE-inhibitor
therapy for cardiovascular protection.
Dual-Chamber Versus Single-Chamber Detection Enhancements for Implantable
Defibrillator Rhythm Diagnosis
The Detect Supraventricular Tachycardia Study
Circulation. 2006;113:2871-2879
Paul A. Friedman, MD; Robyn L. McClelland,
PhD; William R. Bamlet, MS; Helbert Acosta, MD; David Kessler, MD; Thomas M.
Munger, MD; Neal G. Kavesh, MD; Mark Wood, MD; Emile Daoud, MD; Ali Massumi, MD;
Claudio Schuger, MD; Stephen Shorofsky, MD; Bruce Wilkoff, MD; Michael Glikson,
MD
Background— Delivery of
inappropriate shocks caused by misdetection of supraventricular tachycardia
(SVT) remains a substantial complication of implanted cardioverter/defibrillator
(ICD) therapy. Whether use of optimally programmed dual-chamber ICDs lowers this
risk compared with that in single-chamber ICDs is not clear.
Methods and Results— Subjects with a clinical indication for ICD (n=400) at 27
participating centers received dual-chamber ICDs and were randomly assigned to
strictly defined optimal single- or dual-chamber detection in a single-blind
manner. Programming minimized ventricular pacing. The primary end point was the
proportion of SVT episodes inappropriately detected from the time of programming
until crossover or end of study. On a per-episode basis, 42% of the episodes in
the single-chamber arm and 69% of the episodes in the dual-chamber arm were due
to SVT. Mortality (3.5% in both groups) and early study withdrawal (14%
single-chamber, 11% dual-chamber) were similar in both groups. The rate of
inappropriate detection of SVT was 39.5% in the single-chamber detection arm
compared with 30.9% in the dual-chamber arm. The odds of inappropriate detection
were decreased by almost half with the use of the dual-chamber detection
enhancements (odds ratio, 0.53; 95% confidence interval, 0.30 to 0.94; P=0.03).
Conclusions— Dual-chamber ICDs, programmed to optimize detection enhancements
and to minimize ventricular pacing, significantly decrease inappropriate
detection.
Prevention of Ventricular Desynchronization by Permanent Para-Hisian Pacing
After Atrioventricular Node Ablation in Chronic Atrial Fibrillation. A
Crossover, Blinded, Randomized Study Versus Apical Right Ventricular Pacing
J Am Coll Cardiol 47: 1938-1945
Eraldo Occhetta, MD, Miriam Bortnik, MD,
Andrea Magnani, MD, Gabriella Francalacci, MD, Cristina Piccinino, MD, Laura
Plebani, PhD and Paolo Marino, MD, FESC
OBJECTIVES: The aim of our
study was to evaluate the feasibility, the safety, and hemodynamic improvements
induced by permanent para-Hisian pacing in patients with chronic atrial
fibrillation and narrow QRS who underwent atrioventricular (AV) node ablation.
BACKGROUND: Right ventricular apical pacing, inducing asynchronous ventricular
contraction, may impair cardiac function; permanent para-Hisian pacing could
preserve interventricular synchrony and improve left ventricular function.
METHODS: After AV node ablation, 16 patients were implanted with a dual-chamber
pacemaker connected to a screw-in lead positioned in close proximity to the His
bundle and to a right ventricular apical lead. Clinical and echocardiographic
data were collected at baseline and after two randomized six-month periods (with
para-Hisian and conventional pacing).
RESULTS: During para-Hisian pacing, the interventricular electromechanical delay
improved as well (34 ± 18 ms) as during right apical pacing (47 ± 19 ms), p <
0.05. Para-Hisian pacing allowed an improvement in New York Heart Association
functional class (1.75 ± 0.4 vs. 2.33 ± 0.6 at baseline and 2.5 ± 0.4 during
apical pacing, p < 0.05 for both), in quality-of-life score (16.2 ± 8.7 vs. 32.5
± 15.0 at baseline, p < 0.05), and in the 6-min walk test (431 ± 73 m vs. 378 ±
60 m at baseline and 360 ± 71 m during apical pacing, p < 0.5 for both). Mitral
and tricuspid regurgitation improved during para-Hisian pacing (1.22 ± 0.8 and
1.46 ± 0.5 index, respectively, vs. 1.68 ± 0.6 [p < 0.05] and 1.62 ± 0.7 [p =
NS] index at baseline, respectively), with a slight worsening during apical
pacing (1.93 ± 1 and 1.93 ± 0.7 index, respectively, p < 0.05 for both).
CONCLUSIONS: Permanent para-Hisian pacing is feasible and safe. Compared with
conventional right apical pacing, it allows an improvement in
functional and hemodynamic parameters over long-term follow-up.
Heart Disease Risk Determines Menopausal Age Rather Than the Reverse
J Am Coll Cardiol 47: 1976-1983
Helen S. Kok, MD, PhD, Kristel M. van
Asselt, MD, PhD, Yvonne T. van der Schouw, PhD, Ingeborg van der Tweel, PhD,
Petra H.M. Peeters, MD, PhD, Peter W.F. Wilson, MD, PhD, Peter L. Pearson, MD,
PhD and Diederick E. Grobbee, MD, PhD
OBJECTIVES: The purpose of
this study was to investigate whether a harmful cardiovascular risk profile
accelerates menopause.
BACKGROUND: Women with an early menopause are at an increased risk of
cardiovascular disease. Although increased cardiovascular risk has been proposed
as consequence of menopause, the alternative hypothesis, that increased
premenopausal cardiovascular risk promotes early menopause, needs to be
examined.
METHODS: We used data from the Framingham Heart Study cohort. This study started
in 1948 and has followed up participants biennially since then. Women who were
premenopausal at study entry and who reached natural menopause after at least
two examination rounds were included in the study (n = 695). Premenopausal
age-independent levels of serum total cholesterol, relative weight, blood
pressure, and Framingham risk score were determined, as well as premenopausal
changes in cholesterol, body weight, and blood pressure.
RESULTS: A higher premenopausal serum total cholesterol level was statistically
significantly associated with an earlier age at menopause, as were increases in
total serum cholesterol, relative weight, and blood pressure in the
premenopausal period. A decrease in total serum cholesterol during premenopause
was statistically significantly associated with later age at menopause.
Decreasing blood pressure was associated with a later menopausal age, but this
association was not statistically significant. A decrease in relative weight was
associated with a significant earlier age at menopause. Each 1% higher
premenopausal Framingham risk score was associated with a decrease in menopausal
age of 1.8 years (95% confidence interval –2.72 to –0.92).
CONCLUSIONS: The findings support the view that heart disease risk determines
age at menopause. This offers a novel explanation for the inconsistent findings
on cardiovascular disease rate and its relationship to menopausal age and
effects of hormone replacement therapy.
Implantable cardioverter-defibrillator therapy and risk of congestive heart
failure or death in MADIT II patients with atrial fibrillation
Heart Rhythm, Volume 3, Issue 6,
Pages 631-637 (June 2006)
Wojciech Zareba, MD, PhD , Jonathan S.
Steinberg, MD, Scott McNitt, MS, James P. Daubert, MD, Katarzyna Piotrowicz, MD,
Arthur J. Moss, MD
Background Atrial
fibrillation (AF) contributes to increased risk of morbidity and mortality. Data
regarding the effectiveness of implantable cardioverter-defibrillator (ICD)
therapy in AF patients are limited.
Objectives The purpose of this study was to evaluate the effectiveness of ICD
therapy in patients with AF enrolled in the Multicenter Automatic Defibrillator
Implantation Trial II (MADIT II) and to identify their risk for the combined
endpoint of hospitalization for congestive heart failure or death.
Methods The MADIT II cohort served as the source for data on the clinical
course, cardiac events, and effectiveness of ICD therapy in AF patients.
Results AF was found as baseline rhythm at enrollment in 102 (8%) MADIT II
patients. In comparison to 1,007 patients in sinus rhythm, AF patients were
older, more frequently were males, had wider QRS complex, and had higher blood
urea nitrogen and creatinine levels (P <.05 for all parameters). ICD therapy was
effective in reducing 2-year mortality in AF patients from 39% in 41
conventionally treated patients to 22% in 61 ICD-treated patients (hazard ratio
= 0.51, P = .079). However, the combined endpoint of hospitalization for heart
failure or death at 2 years was 69% and 59%, respectively (NS). AF was
predictive for the combined endpoint of heart failure hospitalization or death
(hazard ratio = 1.68, P = .040). New-onset AF in patients with baseline sinus
rhythm was associated with increased risk of mortality (hazard ratio = 2.70, P
<.001).
Conclusion MADIT II patients with AF benefit from ICD therapy, which reduces
their mortality. MADIT II patients with AF are at high risk for developing heart
failure.
Time Dependence of Defibrillator Benefit After Coronary Revascularization in the
Multicenter Automatic Defibrillator Implantation Trial (MADIT)-II
J Am Coll Cardiol 47: 1811-1817
Ilan Goldenberg, MD, Arthur J. Moss, MD,
Scott McNitt, MS, Wojciech Zareba, MD, PhD, W. Jackson Hall, PhD , Mark L.
Andrews, BBS, David J. Wilber, MD , Helmut U. Klein, MD for the MADIT-II
Investigators
OBJECTIVES: The study was
designed to assess the effect of elapsed time from coronary revascularization
(CR) on the benefit of the implantable cardioverter-defibrillator (ICD) and the
risk of sudden cardiac death (SCD) in patients with ischemic left ventricular
dysfunction.
BACKGROUND: The ICD improves survival in appropriately selected high-risk
cardiac patients by 30% to 54%. However, in the Coronary Artery Bypass Graft
(CABG)-Patch trial no evidence of improved survival was shown among a similar
population of patients in whom an ICD was implanted prophylactically at the time
of elective CABG.
METHODS: The outcome by time from CR was analyzed in 951 patients in whom a
revascularization procedure was performed before enrollment in the Multicenter
Automatic Defibrillator Implantation Trial (MADIT)-II.
RESULTS: The adjusted hazard ratio (HR) of ICD versus conventional therapy was
0.64 (p = 0.01) among patients enrolled more than six months after CR, whereas
no survival benefit with ICD therapy was shown among patients enrolled six
months or earlier after CR (HR = 1.19; p = 0.76). In the conventional therapy
group, the risk of cardiac death increased significantly with increasing time
from CR (p for trend = 0.009), corresponding mainly to a six-fold increase in
the risk of SCD among patients enrolled more than six months after CR.
CONCLUSIONS: In patients with ischemic
left ventricular dysfunction, the efficacy of ICD therapy after CR is time
dependent, with a significant life-saving benefit in patients receiving device
implantation more than six months after CR. The lack of ICD benefit when
implanted early after CR may be related to a relatively low risk of SCD during
this time period.
Aspirin Use and Outcomes in a Community-Based Cohort of 7352 Patients Discharged
After First Hospitalization for Heart Failure
Circulation. 2006;113:2572-2578
Finlay A. McAlister MD, MSc, William A.
Ghali MD, MPH, Yanyan Gong MSc, Jiming Fang PhD, Paul W. Armstrong MD, and Jack
V. Tu MD, PhD
Background--The safety of
aspirin in heart failure (HF) has been called into question, particularly in
those patients (1) without coronary disease, (2) with renal dysfunction, or (3)
treated with low-dose angiotensin-converting enzyme (ACE) inhibitors and
high-dose aspirin.
Methods and Results--We examined prescription patterns and outcomes (all-cause
mortality and/or HF readmission) in patients discharged from 103 Canadian
hospitals between April 1999 and March 2001 after a first hospitalization for HF.
Of 7352 patients with HF (mean age, 75 years; 44% without coronary disease and
29% with renal dysfunction), 2785 (38%) died or required HF readmission within
the first year. Compared with nonusers, aspirin users were no more likely to die
or require HF readmission (hazard ratio [HR], 1.02 [0.91 to 1.16]), even in
patients without coronary disease (HR, 0.98 [0.78 to 1.22]) or patients with
renal dysfunction (HR, 1.13 [0.94 to 1.36]). On the other hand, users of ACE
inhibitors were less likely to die or require HF readmission (HR, 0.87 [0.79 to
0.96]), even if they were using aspirin (HR, 0.86 [0.77 to 0.95]). There were no
dose-dependent interactions between aspirin and ACE inhibitors.
Conclusions--In this observational study,
aspirin use was not associated with an
increase in mortality rates or HF readmission rates, and aspirin did not
attenuate the benefits of ACE inhibitors, even in patients without coronary
disease, patients with renal dysfunction, or patients treated with high-dose
aspirin and low-dose ACE inhibitors.
Prospective study of alcohol drinking patterns and coronary heart disease in
women and men
BMJ 2006;332:1244-1248 (27 May)
Janne Tolstrup, research fellow, Majken K
Jensen, research fellow, Anne Tjønneland, senior research fellow, Kim Overvad,
research director, Kenneth J Mukamal, assistant professor, Morten Grønbæk,
professor
Objective To determine the
association between alcohol drinking patterns and risk of coronary heart disease
in women and men.
Design Population based cohort study.
Setting Denmark, 1993-2002.
Participants 28 448 women and 25 052 men aged 50-65 years, who were free of
cardiovascular disease at entry to the study.
Main outcome measures Incidence of coronary heart disease occurring during a
median follow-up period of 5.7 years.
Results 749 and 1283 coronary heart disease events occurred among women and men.
Women who drank alcohol on at least one day a week had a lower risk of coronary
heart disease than women who drank alcohol on less than one day a week. Little
difference was found, however, between drinking frequency: one day a week
(hazard ratio 0.64, 95% confidence interval 0.51 to 0.81), 2-4 days a week
(0.63, 0.52 to 0.77), five or six days a week (0.79, 0.61 to 1.03), and seven
days a week (0.65, 0.51 to 0.84). For men an inverse association was found
between drinking frequency and risk of coronary heart disease across the entire
range of drinking frequencies. The lowest risk was observed among men who drank
daily (0.59, 0.48 to 0.71) compared with men who drank alcohol on less than one
day a week.
Conclusions Among women alcohol intake may be the primary determinant of the
inverse association between drinking alcohol and risk of coronary heart disease
whereas among men, drinking frequency, not alcohol intake, seems more important.
Cryoablation versus radiofrequency ablation for treatment of pediatric
atrioventricular nodal reentrant tachycardia: Initial experience with 4-mm
cryocatheter
Heart Rhythm, Volume 3, Issue 5,
Pages 564-570 (May 2006)
Kathryn K. Collins, MD , Anne M. Dubin,
MD, Nancy A. Chiesa, RN, Kishor Avasarala, MD, George F. Van Hare, MD
Background Initial reports
have shown cryoablation to be safe and efficacious for treatment of
atrioventricular nodal reentrant tachycardia (AVNRT). No direct comparisons of
cryoablation vs radiofrequency (RF) catheter ablation in pediatric patients have
been made.
Objectives The purpose of this study was to compare the outcomes of cryothermal
vs RF catheter ablation for treatment of AVNRT in pediatric patients.
Methods We retrospectively reviewed consecutive ablation procedures for
treatment of AVNRT at a single arrhythmia center. The RF group consisted of
patients who underwent RF ablation from 2002 until cryothermy became available.
The cryoablation group consisted of patients who underwent cryothermal ablation
from 2004 to 2005. The groups were compared for procedural and
electrophysiologic outcomes.
Results RF (n = 60, age 14 ± 4 years) and cryoablation (n = 57, age 14 ± 4
years) groups had similar demographic and baseline parameters. Procedural times
were shorter in the RF group (RF ablation 112 ± 31 minutes vs cryoablation 148 ±
46 minutes, P <.001). Fluoroscopy times were comparable (RF ablation 21 ± 15
minutes vs cryoablation 20 ± 13 minutes, P = .77). In an intention-to-treat
analysis, success of the procedure was 100% for RF ablation and 95% for
cryoablation (P = .11). No permanent AV block occurred in either group.
Recurrence rates were higher for the cryoablation group, but this did not reach
statistical significance (RF ablation 2% vs cryoablation 8%, P = .19).
Conclusion Cryoablation appears to be similar to RF for ablation of AVNRT with
respect to short-term efficacy and safety of the procedure in a pediatric
population. Recurrence rates are higher with cryoablation.
Effects of a rate smoothing algorithm for prevention of ventricular arrhythmias:
Results of the Ventricular Arrhythmia Suppression Trial (VAST)
Heart Rhythm, Volume 3, Issue 5,
Pages 573-580 (May 2006)
Paul A. Friedman, MD , Sohail Jalal, MD,
Scott Kaufman, MD, Rollo Villareal, MD, Scott Brown, PhD, Stephen J. Hahn, PhD,
Darin R. Lerew, PhD
Background Rate smoothing,
which is available in some pacemakers and implantable cardioverter
defibrillators (ICDs), has been used to prevent Torsades de Pointes in patients
with long QT syndrome. Its efficacy in general ventricular arrhythmia prevention
has not been determined.
Objectives The purpose of the Ventricular Arrhythmia Suppression Trial (VAST)
was to prospectively investigate whether rate smoothing could significantly
reduce the incidence of ventricular tachyarrhythmias in a large, broad
population of patients with ICDs.
Methods Five hundred sixty-nine patients were enrolled at 57 participating
centers and implanted with a commercially available Guidant ICD. A
single-blinded crossover design was used in which each patient was randomized at
implant to one of two treatment sequences: either rate smoothing on (RS On)
followed by rate smoothing off (RS Off), or RS Off followed by RS On. This mode
sequence was randomly determined and assigned in a 1:1 fashion using randomized
permuted blocks by site. Each mode was followed for 6 months. Programming of
rate smoothing was prescribed as 12% Down and 12% Up for the duration of the RS
On period.
Results Of enrolled patients, 281 were randomized to RS Off followed by RS On,
and 288 to RS On followed by RS Off. With RS On, 75 (23%) patients experienced a
reduction in arrhythmias, 76 (23%) saw an increase in arrhythmias, and the
remaining 176 (54%) had no difference. No significant difference (P = .58) in
frequency of arrhythmias with RS On vs RS Off was found.
Conclusion Rate smoothing does not
result in a reduction in ventricular arrhythmias in a heterogenous population of
patients receiving ICDs.
Pacemaker implantation and quality of life in the Mode Selection Trial (MOST)
Heart Rhythm, Volume 3, Issue 6,
Pages 653-659 (June 2006)
Kirsten E. Fleischmann, MD, MPH , E. John
Orav, PhD, Gervasio A. Lamas, MD, Carol M. Mangione, MD, MSPH, Eleanor Schron,
MS, RN, Kerry L. Lee, PhD, Lee Goldman, MD, MPH
Background Dual-chamber
pacemakers restore AV synchrony compared with ventricular pacemakers, but the
effects on health-related quality of life (QOL) are uncertain.
Objectives The purpose of this study was to assess the effect of pacemaker
implantation, clinical factors, and pacing mode on QOL.
Methods The Mode Selection Trial (MOST) randomized 2,010 patients with sinus
node dysfunction to rate-modulated right ventricular (VVIR) or dual-chamber (DDDR)
pacing. A longitudinal analysis of serial QOL measures (Short Form-36 [SF-36],
Specific Activity Scale, and time trade-off utility) was performed. In patients
who crossed over from VVIR to DDDR because of severe pacemaker syndrome, the
last known QOL prior to crossover was carried forward.
Results Pacemaker implantation resulted in substantial improvement in almost all
QOL measures. Subjects 75 years or older experienced significantly less
improvement in functional status and physical component summary scores than did
younger subjects. In longitudinal analyses of the effect of pacing mode on QOL,
significant improvement in three SF-36 subscales was observed with DDDR pacing
compared with VVIR pacing: role physical [62.8 points (95% confidence interval
[CI] 60.2, 65.5) vs 56.4 (95% CI 53.7, 59.1)], role emotional [85.0 (95% CI
82.9, 87.0) vs 81.9 (95% CI 79.9, 84.0)], and vitality [51.8 (95% CI 50.3, 53.3)
vs 49.3 (95% CI 47.8, 50.7)], but not in other SF-36 subscales, the Specific
Activity Scale, or utilities. The gains in QOL were larger than the declines
associated with 1 year of aging but smaller than those associated with heart
failure.
Conclusion Pacemaker implantation improved health-related QOL. The mode selected
was associated with much smaller, but significant, improvements in several
domains, particularly role physical function.
Vagal denervation and atrial fibrillation inducibility: Epicardial fat pad
ablation does not have long-term effects
Heart Rhythm, Volume 3, Issue 6,
Pages 701-708 (June 2006)
Seil Oh, MD, PhD, Youhua Zhang, MD, PhD,
Steve Bibevski, MD, PhD, Nassir F. Marrouche, MD, Andrea Natale, MD, Todor N.
Mazgalev, PhD
Background Major epicardial
fat pads contain cardiac ganglionated plexi of the autonomic, predominantly
vagal nerves. Vagal denervation may improve the success rate of atrial
fibrillation (AF) treatment.
Objectives The purpose of this study was to elucidate the long-term effects of
fat pad ablation on the electrophysiologic characteristics of the atrium and AF
inducibility.
Methods Six mongrel dogs were studied. Cervical vagal stimulation was applied to
determine effects on the sinus node, AV node, atrial effective refractory period
(AERP), and AF inducibility. AERP and AF inducibility were evaluated at both the
right atrial and left atrial appendages and at the right atrial and left atrial
free walls. Radiofrequency energy was delivered epicardially to the entire areas
of two major fat pads: right pulmonary vein fat pad and inferior vena cava-left
atrium fat pad. Cervical vagal stimulation then was applied to confirm the acute
effects of fat pad ablation. The same evaluation was repeated 4 weeks later.
Results The effects of vagal stimulation on the sinus node, AV node, and AERP
were significantly eliminated immediately after fat pad ablation. However, these
denervation effects disappeared after 4 weeks. At baseline, AF inducibility was
increased by vagal stimulation (right atrial appendage: 72% ± 31% vs 4.8% ± 12%;
right atrial free wall: 75% ± 31% vs 0.0% ± 0.0%; left atrial appendage: 60% ±
29% vs 0.0% ± 0.0%; left atrial free wall: 65% ± 42% vs 0.0% ± 0.0%). Fat pad
ablation significantly reduced this vagal stimulation effect (8.3% ± 20%, 10% ±
22%, 17% ± 29%, and 25% ± 29%, respectively). However, similar to baseline, AF
inducibility was strongly augmented by vagal stimulation 4 weeks after fat pad
ablation (96% ± 10%, 100% ± 0.0%, 100% ± 0.0%, and 95% ± 11%, respectively).
Conclusion Radiofrequency fat pad
ablation may not achieve long-term suppression of AF induction in this canine
model.
Prognostic Utility of Microvolt T-Wave Alternans in Risk Stratification of
Patients With Ischemic Cardiomyopathy
J Am Coll Cardiol 47: 1820-1827
Theodore Chow, MD, FACC, Dean J. Kereiakes,
MD, FACC, Cheryl Bartone, RN, Terri Booth, RN, Edward J. Schloss, MD, FACC,
Theodore Waller, MD, FACC, Eugene S. Chung, MD, Santosh Menon, MD, Brahmajee K.
Nallamothu, MD, MPH and Paul S. Chan, MD, MSc
OBJECTIVES: The purpose of
this study was to assess if microvolt T-wave alternans (MTWA) is an independent
predictor of mortality in patients with ischemic cardiomyopathy.
BACKGROUND: Microvolt T-wave alternans has been proposed as an effective tool
for identifying high-risk patients with ischemic cardiomyopathy who are likely
to benefit from implantable cardioverter-defibrillator (ICD) therapy. However,
earlier studies have been limited in their ability to control for baseline
differences between MTWA-negative and -non-negative (positive and indeterminate)
patients.
METHODS: We enrolled 768 consecutive patients with ischemic cardiomyopathy (left
ventricular ejection fraction 35%) and no prior history of ventricular
arrhythmia. All patients underwent baseline MTWA testing and were classified as
MTWA negative or non-negative. Multivariable Cox regression analyses, stratified
by ICD status, were used to determine the association between MTWA testing and
mortality after adjusting for demographic, clinical, and treatment differences
between MTWA-negative and -non-negative patients.
RESULTS: We identified 514 (67%) patients with a non-negative MTWA test. After
multivariable adjustment, a non-negative MTWA test was associated with a
significantly higher risk for all-cause (stratified hazard ratio [HR] = 2.24
[95% confidence interval 1.34 to 3.75]; p = 0.002) and arrhythmic mortality
(stratified HR = 2.29 [1.00 to 5.24]; p = 0.049) but not for nonarrhythmic
mortality (stratified HR = 1.77 [0.84 to 3.74]; p = 0.13). In subgroup analyses,
a non-negative MTWA test was also associated with a higher risk for all-cause
mortality in patients with ejection fractions 30% (stratified HR = 2.10 [1.18 to
3.73]; p = 0.01) and after excluding those with indeterminate MTWA tests
(stratified HR = 2.08 [1.18 to 3.66]; p = 0.01).
CONCLUSIONS: Microvolt T-wave alternans is a strong and independent predictor of
all-cause and arrhythmic mortality in patients with ischemic cardiomyopathy.
Radiation Exposure of Computed Tomography and Direct Intracoronary Angiography
Risk Has its Reward
J Am Coll Cardiol 47: 1846-1849
Pat Zanzonico, PhD, Lawrence N.
Rothenberg, PhD and H. William Strauss, MD
A hallmark of noninvasive
testing has been the identification of patients with coronary artery disease.
Now, with multislice computed tomography (MSCT), information about coronary
anatomy can be obtained without the need for catheterization. A major concern
with the application of MSCT coronary angiography is the radiation exposure to
the patient. Both MSCT and selective coronary angiography share the risks of
procedure-related complications, such as allergic contrast reactions, and
stochastic risks (i.e., cancer induction) of low-level radiation. There is
a substantially higher radiation dose
for MSCT angiography (effective dose [ED] 14 mSv) than for CCA (ED 6 mSv).
These exposures yield lifetimes risks of 0.07% and 0.02%, respectively, of
inducing a fatal cancer in the general (i.e., age- and gender-averaged)
population. However, CCA poses
additional serious risks associated with cardiac catheterization,
yielding a non-radiogenic risk of mortality—excluding contrast reactions—of
0.11%. Combining the radiogenic and non-radiogenic risks (0.02% and 0.11%,
respectively) yields a 0.13% overall risk of
mortality from CCA—nearly two-fold
higher than that for MSCT angiography (0.07%). If one were to use the
lower, more age-appropriate risk factors for the older patient population in
question, the radiogenic risks of both CCA and MSCT would be reduced by about
one-half, further widening the overall safety ratio of MSCT relative to CCA.
When weighing the relative risks of alternative medical procedures, therefore,
it is imperative that one consider the overall risk of the respective
procedures.
Causes and Consequences of Heart Failure After Prophylactic Implantation of a
Defibrillator in the Multicenter Automatic Defibrillator Implantation Trial II
Circulation 2006 Published online
before print June 12, 2006
Ilan Goldenberg MD, Arthur J. Moss MD, W.
Jackson Hall PhD, Scott McNitt MS, Wojciech Zareba MD, PhD, Mark L. Andrews BBS,
David S. Cannom MD, for the Multicenter Automatic Defibrillator Implantation
Trial (MADIT) II Investigators
Background--Implantable
cardioverter-defibrillator (ICD) therapy may be associated with an increased
risk for heart failure (HF). The present study evaluated the frequency, causes,
and consequences of HF after ICD implantation.
Methods and Results--We performed a retrospective analysis of the clinical
factors and outcomes associated with postenrollment HF events in 1218 patients
enrolled in the Multicenter Automatic Defibrillator Implantation Trial II. The
adjusted hazard ratios (HRs) of ICD:conventional therapy for first and recurrent
HF events were 1.39 (P=0.02) and 1.58 (P<0.001), respectively. The risk was
increased among patients who received single-chamber or dual-chamber ICDs.
Development of HF was associated with an increased mortality risk (HR, 3.80;
P<0.001). Among patients who received a single-chamber ICD, there was a similar
survival benefit before and after the development of HF (HR, 0.59 and 0.61,
respectively; P=0.92 for difference), whereas among patients with dual-chamber
devices, there was a significant reduction in survival benefit after HF (HR,
0.26 and 0.83, respectively; P=0.01 for difference). Within the defibrillator
arm of the trial, patients who received life-prolonging therapy from the ICD had
an increased risk for first and recurrent HF events (HR, 1.90; P=0.01 and 1.74;
P<0.001, respectively).
Conclusions--Patients with chronic ischemic heart disease who are treated with
either single-chamber or dual-chamber ICDs have improved survival but an
increased risk of HF. The present data suggest that
ICD therapy transforms sudden death risk
to a subsequent HF risk. These findings should direct more attention to
the prevention of HF in patients who receive an ICD.
New Insights Into the Initiation of Atrial Fibrillation A Detailed
Intraindividual and Interindividual Analysis of the Spontaneous Onset of Atrial
Fibrillation Using New Diagnostic Pacemaker Features
Circulation. 2006;113:1933-1941
Ellen Hoffmann, MD; Neil Sulke, MD; Nils
Edvardsson, MD; Jacob Ruiter, MD; Thorsten Lewalter, MD; Alessandro Capucci, MD;
Andreas Schuchert, MD; Sabine Janko, MD; John Camm, MD, on behalf of the Atrial
Fibrillation Therapy (AFT) Trial Investigators
Background— This study
investigated onset scenarios of atrial fibrillation (AF), the first phase of the
Atrial Fibrillation Therapy (AFT) trial, to determine potential arrhythmogenic
triggers as targets for atrial pacing algorithms that have been proposed for
prevention of AF.
Methods and Results— Ninety-eight patients (58 men; age 65±11 years) with
recurrent, symptomatic, drug-refractory AF and a conventional pacemaker
indication in 31 of 98 received a dual-chamber pacemaker. Using novel diagnostic
pacemaker features AF onset scenarios were prospectively evaluated in 612 AF
episodes during a 2-month monitoring period, with atrial pacing limited to 40
bpm. The most common onset scenario was premature atrial complexes (PACs) before
AF (48% onsets per patient), followed by bradycardia (33%), sudden onset (17%),
and tachycardia (0%). Combinations of onset scenarios were frequent (median 2
different scenarios per patient). A main study finding was the significance of
repetitive AF, with 33% of onsets per patient being initiated within 5 minutes
of a previous AF episode. Sudden onsets were more frequent among patients with
than without repetitive AF (24% versus 0% onsets per patient, P=0.011), whereas
the proportion of PACs before AF was not statistically different (50% versus
37%, P=0.52); however, patients with repetitive AF had more PACs per hour (72
versus 29, P=0.023) and a higher number of AF episodes per day (17 versus 0,
P=0.001) and were more likely to have at least 1 PAC-related onset (90% versus
53%, P<0.0001).
Conclusions— Novel diagnostic pacemaker features allowed a detailed individual
analysis of rate and rhythm changes before AF and thus uncovered a substantial
intraindividual and interindividual variability of AF onset scenarios.
Role of Diuretics in the Prevention of Heart Failure The Antihypertensive and
Lipid-Lowering Treatment to Prevent Heart Attack Trial
Circulation. 2006;113:2201-2210
Barry R. Davis, MD, PhD; Linda B. Piller,
MD, MPH; Jeffrey A. Cutler, MD, MPH; Curt Furberg, MD, PhD; Kay Dunn, PhD;
Stanley Franklin, MD; David Goff, MD, PhD; Frans Leenen, MD, PhD; Syed Mohiuddin,
MD; Vasilios Papademetriou, MD; Michael Proschan, PhD; Allan Ellsworth, PharmD;
John Golden, MD; Pedro Colon, MD; Richard Crow, MD, for the Antihypertensive and
Lipid-Lowering Treatment to Prevent Heart Attack Trial (ALLHAT) Collaborative
Research Group
Background— Hypertension is a
major cause of heart failure (HF) and is antecedent in 91% of cases. The
Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial (ALLHAT)
stipulated assessment of the relative effect of chlorthalidone, lisinopril, and
amlodipine in preventing HF.
Methods and Results— ALLHAT was a double-blind, randomized, clinical trial in 33
357 high-risk hypertensive patients aged 55 years. Hospitalized/fatal HF
outcomes were examined with proportional-hazards models. Relative risks (95%
confidence intervals; P values) of amlodipine or lisinopril versus
chlorthalidone were 1.35 (1.21 to 1.50; <0.001) and 1.11 (0.99 to 1.24; 0.09).
The proportional hazards assumption of constant relative risk over time was not
valid. A more appropriate model showed relative risks of amlodipine or
lisinopril versus chlorthalidone during year 1 were 2.22 (1.69 to 2.91; <0.001)
and 2.08 (1.58 to 2.74; <0.001), and after year 1, 1.22 (1.08 to 1.38; P=0.001)
and 0.96 (0.85 to 1.10; 0.58). There was no significant interaction between
prior medication use and treatment. Baseline blood pressures were equivalent
(146/84 mm Hg) and at year 1 were 137/79, 139/79, and 140/80 mm Hg in those
given chlorthalidone, amlodipine, and lisinopril. At 1 year, use of added
open-label atenolol, diuretics, angiotensin-converting enzyme inhibitors, and
calcium channel blockers in the treatment groups was similar.
Conclusions— HF risk decreased with
chlorthalidone versus amlodipine or lisinopril use during year 1.
Subsequently, risk for those individuals taking chlorthalidone versus amlodipine
remained decreased but less so, whereas it was equivalent to those given
lisinopril. Prior medication use, follow-up blood pressures, and concomitant
medications are unlikely to explain most of the HF differences. Diuretics are
superior to calcium channel blockers and, at least in the short term,
angiotensin-converting enzyme inhibitors in preventing HF in hypertensive
individuals.
Outcome of Watchful Waiting in Asymptomatic Severe Mitral Regurgitation
Circulation. 2006;113:2238-2244
Raphael Rosenhek, MD; Florian Rader, MD;
Ursula Klaar, MD; Harald Gabriel, MD; Marcel Krejc, PhD; Daniel Kalbeck, PhD;
Michael Schemper, PhD; Gerald Maurer, MD; Helmut Baumgartner, MD
Background— The management of
asymptomatic severe mitral regurgitation remains controversial. The aim of this
study was to evaluate the outcome of a watchful waiting strategy in which
patients are referred to surgery when symptoms occur or when asymptomatic
patients develop left ventricular (LV) enlargement, LV dysfunction, pulmonary
hypertension, or recurrent atrial fibrillation.
Methods and Results— A total of 132 consecutive asymptomatic patients (age 55±15
years, 49 female) with severe degenerative mitral regurgitation (flail leaflet
or valve prolapse) were prospectively followed up for 62±26 months. Patients
underwent serial clinical and echocardiographic examinations and were referred
for surgery when the criteria mentioned above were fulfilled. Overall survival
was not statistically different from expected survival either in the total group
or in the subgroup of patients with flail leaflet. Eight deaths were observed.
Thirty-eight patients developed criteria for surgery (symptoms, 24; LV criteria,
9; pulmonary hypertension or atrial fibrillation, 5). Survival free of any
indication for surgery was 92±2% at 2 years, 78±4% at 4 years, 65±5% at 6 years,
and 55±6% at 8 years. Patients with flail leaflet tended to develop criteria for
surgery slightly but not significantly earlier. There was no operative
mortality. Postoperative outcome was good with regard to survival, symptomatic
status, and postoperative LV function.
Conclusions— Asymptomatic patients with severe degenerative mitral regurgitation
can be safely followed up until either
symptoms occur or currently recommended cutoff values for LV size, LV function,
or pulmonary hypertension are reached. This management strategy is
associated with good perioperative and postoperative outcome but requires
careful follow-up.
Coffee Consumption and Coronary Heart Disease in Men and Women A Prospective
Cohort Study
Circulation. 2006;113:2045-2053
Esther Lopez-Garcia, DrPH; Rob M. van Dam,
PhD; Walter C. Willett, MD, DrPH; Eric B. Rimm, ScD; JoAnn E. Manson, MD, DrPH;
Meir J. Stampfer, MD, DrPH; Kathryn M. Rexrode, MD, MPH; Frank B. Hu, MD, PhD
Background— We examined the
association between long-term habitual coffee consumption and risk of coronary
heart disease (CHD).
Methods and Results— We performed a prospective cohort study with 44 005 men and
84 488 women without history of cardiovascular disease or cancer. Coffee
consumption was first assessed in 1986 for men and in 1980 for women and then
repeatedly every 2 to 4 years; the follow-up continued through 2000. We
documented 2173 incident cases of coronary heart disease (1449 nonfatal
myocardial infarctions and 724 fatal cases of CHD) among men and 2254 cases
(1561 nonfatal myocardial infarctions and 693 fatal cases of CHD) among women.
Among men, after adjustment for age, smoking, and other CHD risk factors, the
relative risks (RRs) of CHD across categories of cumulative coffee consumption
(<1 cup/mo, 1 cup/mo to 4 cups/wk, 5 to 7 cups/wk, 2 to 3 cups/d, 4 to 5 cups/d,
and 6 cups/d) were 1.0, 1.04 (95% confidence interval 0.91 to 1.17), 1.02 (0.91
to 1.15), 0.97 (0.86 to 1.11), 1.07 (0.88 to 1.31), and 0.72 (0.49 to 1.07; P
for trend=0.41); among women, the RRs were 1.0, 0.97 (0.83 to 1.14), 1.02 (0.90
to 1.17), 0.84 (0.74 to 0.97), 0.99 (0.83 to 1.17), and 0.87 (0.68 to 1.11; P
for trend=0.08). Stratification by smoking status, alcohol consumption, history
of type 2 diabetes mellitus, and body mass index gave similar results.
Similarly, we found no effect when the most recent coffee consumption was
examined. RRs for quintiles of caffeine intake varied from 0.97 (0.84 to 1.10)
in the second quintile to 0.97 (0.84 to 1.11) in the highest quintile (P for
trend=0.82) in men and from 1.02 (0.90 to 1.16) to 0.97 (0.85 to 1.11; P for
trend=0.37) in women.
Conclusions— These data do not provide any evidence that coffee consumption
increases the risk of CHD.
Smokers are at markedly increased risk of appropriate defibrillator shocks in a
primary prevention population
Heart Rhythm, Volume 3, Issue 4,
Pages 443-449 (April 2006)
José Mauricio Sánchez, MD , Scott L.
Greenberg, MD, Jane Chen, MD, Marye J. Gleva, MD1, Bruce D. Lindsay, MD2,
Timothy W. Smith, DPhil, MD, Mitchell N. Faddis, MD, PhD
Background Cigarette smoking
is a known risk factor for sudden cardiac death (SCD). It is unknown whether
smoking status affects implantable cardioverter-defibrillator (ICD) therapy.
Objective The primary end point was appropriate ICD therapy according to smoking
status.
Methods A total of 105 consecutive patients who underwent ICD implantation for
primary prevention of SCD were retrospectively analyzed. All patients had an
abnormal response to programmed ventricular stimulation performed for
nonsustained ventricular tachycardia in the setting of ischemic cardiomyopathy
between January 1999 and December 2003.
Results Among the 105 patients, 6 (37.5%) of 16 current smokers, 14 (25.9%) of
54 former smokers, and 2 (5.7%) of 35 of never smokers received an appropriate
ICD therapy (P = .02). Kaplan-Meier analysis for survival free of appropriate
ICD therapy comparing never smokers with both current smokers (P = .002) and
former smokers (P = .01) demonstrated statistically significant differences by
log rank over a mean follow-up of 21.8 ± 13.7 months. Cox regression analysis
found that current smoking was associated with an increased risk of appropriate
therapy (hazard ratio 7.36; 95% confidence interval 1.42–38.10; P = .02) as was
former smoking (hazard ratio 5.42; 95% confidence interval 1.20–24.47; P = .03).
There was no difference in inappropriate therapy between groups (P = .12).
Conclusions Cigarette smoking is an independent predictor of appropriate ICD
therapy in a primary prevention population. While outcomes differences among
current smokers, former smokers, and never smokers are demonstrable, the effect
of smoking cessation on ICD therapy requires further study.
Equivalent arrhythmic risk in patients recently diagnosed with dilated
cardiomyopathy compared with patients diagnosed for 9 months or more
Heart Rhythm, Volume 3, Issue 4,
Pages 397-403 (April 2006)
Kevin J. Makati, MD, Airley E. Fish, MD,
MPH, Hannah H. England, BA, Hocine Tighiouart, MS, N.A. Mark Estes III, MD, Mark
S. Link, MD
Background The Centers for
Medicare and Medicaid Services (CMS) recently expanded coverage for implantable
cardioverter-defibrillators (ICDs) in patients with left ventricular ejection
fraction ≤35% and nonischemic dilated cardiomyopathy for ≥9 months. To
investigate the ramifications of these criteria, the ICD registry from Tufts-New
England Medical Center was analyzed for arrhythmic events and death in patients
with newly diagnosed (<9 months) vs late-diagnosed (≥9 months) nonischemic
dilated cardiomyopathy.
Objectives The purpose of this study was to analyze the arrhythmic risk in
patients with recent vs late diagnosis of nonischemic dilated cardiomyopathy.
Methods One hundred thirty-one patients with nonischemic dilated cardiomyopathy
were divided into two cohorts (<9 or ≥9 months of symptoms) and analyzed for any
occurrence of treated ventricular arrhythmia, potentially lethal arrhythmias
defined as ventricular flutter rates ≥230 bpm, and ventricular fibrillation.
Patients with documented sustained ventricular tachycardias (included in prior
CMS coverage) were excluded.
Results In the study group, the mean age was 58.1 ± 15 years and ejection
fraction 20.6% ± 8%. In a follow-up period of 25.3 ± 24 months, the 52 patients
with a recent diagnosis (1.4 ± 2 months) had no difference in the occurrence of
ventricular arrhythmias (P = .49) and malignant ventricular arrhythmias (P =
.16) compared with the 79 patients diagnosed ≥9 months (mean 58.1 ± 39 months).
Conclusion Patients with nonischemic dilated cardiomyopathy experienced
equivalent occurrences of treated and potentially lethal arrhythmias
irrespective of diagnosis duration. These findings suggest that the
9-month time qualifier used in the CMS guidelines for ICD reimbursement may not
reliably discriminate patients at high risk for sudden cardiac death in
this selected population.
Clopidogrel and Aspirin versus Aspirin Alone for the Prevention of
Atherothrombotic Events
N Engl J Med Volume 354:1706-1717
April 20, 2006
Deepak L. Bhatt, M.D., Keith A.A. Fox, M.B.,
Ch.B., Werner Hacke, M.D., Peter B. Berger, M.D., Henry R. Black, M.D., William
E. Boden, M.D., Patrice Cacoub, M.D., Eric A. Cohen, M.D., Mark A. Creager,
M.D., J. Donald Easton, M.D., Marcus D. Flather, M.D., Steven M. Haffner, M.D.,
Christian W. Hamm, M.D., Graeme J. Hankey, M.D., S. Claiborne Johnston, M.D.,
Koon-Hou Mak, M.D., Jean-Louis Mas, M.D., Gilles Montalescot, M.D., Ph.D.,
Thomas A. Pearson, M.D., P. Gabriel Steg, M.D., Steven R. Steinhubl, M.D.,
Michael A. Weber, M.D., Danielle M. Brennan, M.S., Liz Fabry-Ribaudo, M.S.N.,
R.N., Joan Booth, R.N., Eric J. Topol, M.D., for the CHARISMA Investigators
Background Dual antiplatelet
therapy with clopidogrel plus low-dose aspirin has not been studied in a broad
population of patients at high risk for atherothrombotic events.
Methods We randomly assigned 15,603 patients with either clinically evident
cardiovascular disease or multiple risk factors to receive clopidogrel (75 mg
per day) plus low-dose aspirin (75 to 162 mg per day) or placebo plus low-dose
aspirin and followed them for a median of 28 months. The primary efficacy end
point was a composite of myocardial infarction, stroke, or death from
cardiovascular causes.
Results The rate of the primary efficacy end point was 6.8 percent with
clopidogrel plus aspirin and 7.3 percent with placebo plus aspirin (relative
risk, 0.93; 95 percent confidence interval, 0.83 to 1.05; P=0.22). The
respective rate of the principal secondary efficacy end point, which included
hospitalizations for ischemic events, was 16.7 percent and 17.9 percent
(relative risk, 0.92; 95 percent confidence interval, 0.86 to 0.995; P=0.04),
and the rate of severe bleeding was 1.7 percent and 1.3 percent (relative risk,
1.25; 95 percent confidence interval, 0.97 to 1.61 percent; P=0.09). The rate of
the primary end point among patients with multiple risk factors was 6.6 percent
with clopidogrel and 5.5 percent with placebo (relative risk, 1.2; 95 percent
confidence interval, 0.91 to 1.59; P=0.20) and the rate of death from
cardiovascular causes also was higher with clopidogrel (3.9 percent vs. 2.2
percent, P=0.01). In the subgroup with clinically evident atherothrombosis, the
rate was 6.9 percent with clopidogrel and 7.9 percent with placebo (relative
risk, 0.88; 95 percent confidence interval, 0.77 to 0.998; P=0.046).
Conclusions In this trial, there was a suggestion of benefit with clopidogrel
treatment in patients with symptomatic atherothrombosis and a suggestion of harm
in patients with multiple risk factors. Overall, clopidogrel plus aspirin was
not significantly more effective than
aspirin alone in reducing the rate of myocardial infarction, stroke, or
death from cardiovascular causes.
Effect of antithrombotic therapy in patients with mitral stenosis and atrial
fibrillation: a sub-analysis of NASPEAF randomized trial
Eur Heart J 27: 960-967
Francisco Pérez-Gómez, Antonio Salvador,
Javier Zumalde, Jose A. Iriarte, Jesús Berjón, Eduardo Alegría, Carlos Almería,
Ramón Bover, Dionisio Herrera, Cristina Fernández for the National Study for
Prevention of Embolism in Atrial Fibrillation Investigators
Aims The randomized NASPEAF
study included non-valvular with prior embolism and mitral stenosis patients in
the same group. This is a sub-study to specially focus on the antithrombotic
therapy in mitral stenosis.
Methods and results We analysed 311 patients with mitral stenosis, compared with
175 non-valvular atrial fibrillation patients with prior embolism, stratified by
a history of previous embolism and assigned to anticoagulant therapy [target
international normalized ratio (INR)=2.0–3.0] or combined antiplatelet plus
moderate intensity anticoagulant therapy. Median follow-up was 2.9 years.
Outcomes were fatal and non-fatal embolism, stroke and myocardial infarction,
sudden death, and death from bleeding. Combined therapy in mitral stenosis
patients, compared with anticoagulant alone therapy, reduced the risk of
vascular events by 58.3%. During equal therapy, the outcome annual rates were
essentially the same in non-valvular and valvular patients [hazard ratio 0.90
(95% confidence interval 0.37–2.16), P=0.81]. During anticoagulant alone
therapy, the annual event rate in mitral stenosis patients without prior
embolism was low (2.5%) and it was very high in patients with prior embolism
(6.6%).
Conclusion Combined therapy was
effective in mitral stenosis patients. Prior embolism patients are not
efficiently protected with anticoagulant alone therapy for an INR of 2.0–3.0.
Angiotensin-Converting Enzyme Inhibitors in Coronary Artery Disease and
Preserved Left Ventricular Systolic Function
A Systematic Review and Meta-Analysis of Randomized Controlled Trials
J Am Coll Cardiol 47: 1576-1583
Mouaz H. Al-Mallah, MD, Imad M. Tleyjeh,
MD, Ahmed A. Abdel-Latif, MD and W. Douglas Weaver, MD, FACC
OBJECTIVES: This study sought
to assess the efficacy of angiotensin-converting enzyme inhibitors (ACEIs) in
patients with coronary heart disease and preserved left ventricular (LV)
function.
BACKGROUND: The ACEIs have been shown to improve outcomes in patients with heart
failure and myocardial infarction (MI). However, there is conflicting evidence
concerning the benefits of ACEIs in patients with coronary artery disease (CAD)
and preserved LV systolic function.
METHODS: An extensive search was performed to identify randomized,
placebo-controlled trials of ACEI use in patients with CAD and preserved LV
systolic function. Of 61 potentially relevant articles screened, 6 trials met
the inclusion criteria. They were reviewed to determine cardiovascular
mortality, nonfatal MI, all-cause mortality, and revascularization rates. We
performed random-effect model meta-analyses and quantified between-studies
heterogeneity with I2.
RESULTS: There were 16,772 patients randomized to ACEI and 16,728 patients
randomized to placebo. Use of ACEIs was associated with a decrease in
cardiovascular mortality (relative risk [RR] 0.83, 95% confidence interval [CI]
0.72 to 0.96, p = 0.01), nonfatal MI (RR 0.84, 95% CI 0.75 to 0.94, p = 0.003),
all-cause mortality (RR 0.87, 95% CI 0.81 to 0.94, p = 0.0003), and
revascularization rates (RR 0.93, 95% CI 0.87 to 1.00, p = 0.04). There was no
significant between-studies heterogeneity. Treatment of 100 patients for an
average duration of 4.4 years prevents either of the adverse outcomes (one
death, or one nonfatal myocardial infarction, or one cardiovascular death or one
coronary revascularization procedure).
CONCLUSIONS: The cumulative evidence provided by this meta-analysis shows
a modest favorable effect of
ACEIs on the outcome of patients with CAD and preserved LV systolic function.
Prospective validation of stress echocardiography as an identifier of cardiac
resynchronization therapy responders
Heart Rhythm, Volume 3, Issue 4,
Pages 406-413 (April 2006)
Antoine Da Costa, MD, PhD , Jérǒme
Thévenin, MD, Frédéric Roche, MD, PhD, Emmanuel Faure, MD, Cécile Roméyer-Bouchard,
MD, Marc Messier, PhD, Gilles Convert, MD, Jean Claude Barthélemy, MD, Karl
Isaaz, MD, FACC
Objective The aim of this
prospective study was to assess the predictive role of dobutamine stress
echocardiography (DSE) in identifying a suitable candidate for CRT.
Methods From March 2001 to December 2003, 71 CHF patients were prospectively
enrolled on the basis of four criteria: New York Heart Association (NYHA) class
III and IV; QRS ≥150 ms with a left bundle branch block pattern, and left
ventricular ejection fraction (LVEF) ≤35% under optimal medical treatment. The
combined endpoints were hospital readmission for class IV CHF, heart transplant
(HT), and CHF-related death.
Results The 67 patients completing the study presented with the following
characteristics: age (70 ± 10 years; 11 women); etiology (idiopathic in 44,
ischemic in 23); NYHA class (40 in class III and 27 in class IV); LVEF 26%
(±5%); QRS duration (190 ± 28 ms); 6-minute walk test 330 m (±108); peak oxygen
uptake 10.7 (±3.3 mL/kg/min); mitral insufficiency in 42 (≥III grade);
interventricular (IV) delay (62 ± 21 ms); and intraventricular dyssynchrony in
30 patients. Over the follow-up period of 12.1 ± 8.7 months, 20 (29.9%) of 67
patients presented with at least one hemodynamic event: hospitalization for CHF
in 19 (28%) of 67, HT in 2 (3%) of 67, and CHF death in 7 (10%) 67. Univariate
analysis identified NYHA class (P = .03), LVEF (P = .015), IV dyssynchrony
before (P = .038) and after CRT (P = .0035), IV delay after CRT (P = .002),
6-minute walk distance (P = .01), and DSE Res+ (P = .008) as significant
predictors of clinical events. A receiver operating curve established a cut-off
value of 1.25 for the DSE responders (Res+: 34 patients at 10 μg/kg/min infusion
rates), and the improvement at the 10 μg/kg/min level was 41% ± 7% in Res+ and
29% ± 8% in nonresponders (P<.0001). With a cut-off value of 1.25-fold the LVEF
increase, the DSE test exhibits 70% sensitivity, 61.7% specificity, 43.8%
positive predictive value, and 82.9% negative predictive value. Cox analysis
identified IV dyssynchrony before CRT (P = .01) and DSE Res+ (P = .003) as
independent predictive factors.
Conclusions Independent predictive factors of severe hemodynamic clinical
outcome in patients with CRT are IV dyssynchrony and DSE.
Post-operative use of heparin increases morbidity of pacemaker implantation
Europace 8: 283-287
C. Marquie, G. De Geeter, D. Klug, C.
Kouakam, F. Brigadeau, O. Jabourek, N. Trillot, D. Lacroix and S. Kacet
Aims The objective of this
study is to characterize the incidence of peri-operative severe adverse events (AEs)
related to the post-operative use of heparin in patients undergoing pacemaker
surgery. Methods and results We retrospectively compared the outcome of 38
patients with mechanical valves (MVs) and 76 patients with atrial fibrillation
(AF) with control cases matched for gender, age, and surgical details. Heparin
was systematically used post-operatively in MV patients, but left to clinical
judgment in AF patients. The relative risk for severe haemorrhagic AEs was 11
(CI 1.5–81.1, P<0.01) in the MV group when compared with matched controls and 8
(CI 1.0–62.5, P<0.05) in the AF group. Overall, the relative risk of heparin use
in the post-operative period was 14 (CI 1.88–104, P=0.0006) and the
post-operative stay was prolonged from 7 days in this group when compared with
control cases (P<0.0001).The variables associated with haemorrhage were the
delay to restart heparin after surgery and the presence of an MV.
Conclusion Post-operative use of heparin increases morbidity of pacemaker
implantation. A different approach to management of these patients is possible.
Long-Term Performance of Active-Fixation Pacing Leads: A Prospective Study
PACE 2006; 29:226–230
PETER M. KISTLER, GARY LIEW, and HARRY G.
MOND
Background: Despite the
increasingly widespread use of active-fixation leads, long-term clinical
follow-up of pacing lead outcomes is lacking. The aim was to analyze pacing
parameters over a 2-year follow-up. We performed a prospective observational
study of consecutive new pacemaker implants using the 1488T St. Jude (100) and
the Medtronic 5076 (100) active-fixation leads. Detailed analysis of pacing
parameters was collected at implant, day 1, and 1, 3, 6, 12, 18, and 24 months.
Methods and Results: One hundred patients underwent implantation of 100
dual-chamber pacemakers. Initial pacing parameters in the ventricle were
threshold 0.7 ± 0.2 V, R wave 12.0 ± 6.5 mV, and impedance 879 ± 224 Ω.
Threshold increased significantly from day 1 (0.7 ± 0.2 V) to month 1 (0.9 ± 0.6
V, P < 0.01) and remained stable over the long term. Four of the 100 patients
had a threshold >2 V (mean 3.3 ± 0.9 V) all between day 1 and month 3. For all
patients, R wave remained stable, but impedance declined significantly from day
1 (879 ± 184 Ω) to month 1 (677 ± 122 Ω, P < 0.01). There were no ventricular
lead complications. Initial pacing parameters in the atrium were threshold 0.9 ±
0.3 V, P wave 3.3 ± 2.4 mV, and impedance 606 ± 144 Ω. Threshold remained stable
over the long-term follow-up. One of 100 patients had a rise in threshold >2 V
(2.2 V) between day 1 and month 1. No patients underwent lead repositioning.
Sensing and impedance remained stable over the long term. Patient follow-up was
completed in 94% (6 unrelated deaths). There was an 8% incidence of atrial
fibrillation.
Conclusion: Active-fixation leads are generally associated with stable long-term
pacing parameters.
Differentiating arrhythmogenic right ventricular
cardiomyopathy from right ventricular outflow tract ventricular tachycardia
using multilead QRS duration and axis
Heart Rhythm, Volume 3, Issue 4,
Pages 416-423 (April 2006)
Craig D. Ainsworth, MD, Allan C. Skanes,
MD, George J. Klein, MD, Lorne J. Gula, MD, Raymond Yee, MD, Andrew D. Krahn, MD
Background Ventricular
tachycardia (VT) resulting from arrhythmogenic right ventricular cardiomyopathy
(ARVC) may be difficult to differentiate from idiopathic right ventricular
outflow tract (RVOT) VT.
Objectives The purpose of this study was to investigate the hypothesis that QRS
characteristics would be different in ARVC because of altered conduction through
abnormal myocardium.
Methods In 24 RVOT VT patients (18 women and 6 men; age 42 ± 10 years) and 20
ARVC patients (12 women and 8 men; age 38 ± 14 years), mean QRS duration,
frontal plane axis, and precordial R-wave transition were measured in 12-lead
ECGs recorded during VT.
Results Mean QRS duration was longer in all 12 leads in ARVC patients. A
significant difference was noted in leads I, III, aVL, aVF, V1, V2, and V3 (P
<.05). Leads I and aVL had the largest mean difference between ARVC and RVOT VT
patients of 17.6 ± 4.7 ms and 15.8 ± 7.5 ms, respectively (P <.0001).
Lead I QRS duration ≥120 ms had a
sensitivity of 100%, specificity 46%, positive predictive value 61%, and
negative predictive value 100% for ARVC. The area under the receiver operating
characteristic (ROC) curve was 0.89. The
addition of mean QRS axis <30° (R<S in lead III) to the above criterion
increased specificity for ARVC to 100%. QRS duration remained sensitive
and specific in the subgroup of nine ARVC ECGs with an inferior axis (ROC area
0.82). R-wave transition was not different between groups.
Conclusion QRS duration is longer in ARVC compared with RVOT VT.
An algorithm combining lead I QRS
duration for sensitivity and axis for specificity is useful for differentiating
the two tachycardia substrates.
Aspirin plus warfarin compared to aspirin alone after acute coronary syndromes:
an updated and comprehensive meta-analysis of 25 307 patients
Eur Heart J 27: 519-526
Felicita Andreotti, Luca Testa, Giuseppe
G.L. Biondi-Zoccai and Filippo Crea
Aims In patients recovering
from acute coronary syndromes (ACS) the role of oral anticoagulation (and its
intensity) in addition to aspirin remains controversial. We conducted a specific
meta-analysis of randomized trials comparing aspirin plus warfarin (A+W) with
aspirin alone in such patients.
Methods and results MEDLINE and Cochrane databases yielded 14 (of 148
potentially relevant) articles enrolling 25 307 patients. Follow-up ranged from
3 months to 5 years. Irrespective of International normalized ratio (INR), A+W
did not significantly affect the risk of major adverse events (MAE: all cause
death, non-fatal myocardial infarction, and non-fatal thrombo-embolic stroke)
when compared with aspirin alone [OR 0.96 (0.90–1.03), P=0.30], but increased
the risk of major bleeds (MB): OR 1.77 (1.47–2.13), P<0.00001. However, in
studies with INR of 2–3, A+W was associated with a significant reduction of MAE
[OR 0.73 (0.63–0.84), P<0.0001, number needed to treat to avoid one MAE=33],
albeit at an increased risk of MB [OR 2.32 (1.63–3.29), P<0.00001; number needed
to harm by causing one MB=100]. In both analyses, intracranial bleeding was not
significantly increased by A+W when compared with aspirin alone.
Conclusion For patients recovering from ACS, a combined strategy of A+W at INR
values of 2–3 doubles the risk of MB, but is nonetheless superior to aspirin
alone in preventing MAE. Whether this combined regimen is also superior to a
‘double’ anti-platelet strategy or to newer evolving treatments warrants further
investigation.
Proarrhythmia of Circumferential Left Atrial Lesions for Management of Atrial
Fibrillation
J Cardiovasc Electrophysiol, Vol.
17, pp. 157-165, February 2006
EMILE G. DAOUD, M.D., RAUL WEISS, M.D.,
RALPH AUGOSTINI, M.D., JOHN D. HUMMEL, M.D., STEVEN J. KALBFLEISCH, M.D., JOHN
M. VAN DEREN, M.D.*, GEORGIA DAWSON, R.N., and KATHY BOWMAN, R.N.
Background: After
circumferential ablation for atrial fibrillation, new onset left atrial flutter
(LA Flr) may occur. This study assessed the relationship between induced and
clinical episodes of LA Flr, the rate of spontaneous resolution of LA Flr, and
the proarrhythmic effect of circumferential ablation.
Methods and Results: A total 112 patients underwent circumferential LA ablation
for atrial fibrillation. Immediately after completion of the ablation, LA Flr
was induced in 43 of 112 (38%) patients, but was not targeted for ablation.
During follow-up (14 ± 4 months), new onset LA Flr occurred in 28 of 112 (25%)
patients; however, the presence of inducible LA Flr did not identify those
patients with clinical LA Flr (P = 0.6). In comparison to episodes of atrial
fibrillation occurring before circumferential ablation, LA Flr was associated
with a faster ventricular rate (124 ± 19 beats/min vs 91 ± 16 beats/min, P <
0.001), and was more likely to be persistent requiring cardioversion (86% vs
32%, P = 0.01). By ≥4 months postcircumferential ablation, clinical LA Flr
resolved in 18 of 28 patients (64%). A second ablation procedure for LA Flr was
performed in 9 of 10 patients. Of the 17 morphologies, 16 (94%) LA Flr circuits
were successfully ablated.
Conclusions: (1) LA Flrs that are induced immediately after circumferential
ablation for atrial fibrillation do not identify those patients who require a
second ablation procedure for clinical LA Flr; (2) Since the majority of
clinical LA Flrs spontaneously resolve, ablation of LA Flr should be postponed
several months; and (3) new onset LA Flr after ablation for atrial fibrillation
is likely a manifestation of the proarrhythmic effect of ablation lines in the
LA.
Prospective assessment of integrating the existing emergency medical system with
automated external defibrillators fully operated by volunteers and laypersons
for out-of-hospital cardiac arrest: the Brescia Early Defibrillation Study
(BEDS)
Eur Heart J 27: 553-561
Riccardo Cappato, Antonio Curnis, Paolo
Marzollo, Giosuè Mascioli, Tania Bordonali, Sonia Beretti, Fausto Scalfi, Luca
Bontempi, Adriana Carolei, Gust Bardy, Luigi De Ambroggi and Livio Dei Cas
Aims There are few data on
the outcomes of cardiac arrest (CA) victims when the defibrillation capability
of broad rural and urban territories is fully operated by volunteers and
laypersons.
Methods and results In this study, we investigated whether a programme based on
diffuse deployment of automated external defibrillators (AEDs) operated by 2186
trained volunteers and laypersons across the County of Brescia, Italy (area:
4826 km2; population: 1 112 628), would safely and effectively impact the
current survival among victims of out-of-hospital CA. Forty-nine AEDs were added
to the former emergency medical system that uses manual EDs in the emergency
department of 10 county hospitals and in five medically equipped ambulances. The
primary endpoint was survival free of neurological impairment at 1-year
follow-up. Data were analysed in 692 victims before and in 702 victims after the
deployment of the AEDs. Survival increased from 0.9% (95% CI 0.4–1.8%) in the
historical cohort to 3.0% (95% CI 1.7–4.3%) (P=0.0015), despite similar
intervals from dispatch to arrival at the site of collapse [median (quartile
range): 7 (4) min vs. 6 (6) min]. Increase of survival was noted both in the
urban [from 1.4% (95% CI 0.4–3.4 %) to 4.0% (95% CI 2.0–6.9 %), P=0.024] and in
the rural territory [from 0.5% (95% CI 0.1–1.6%) to 2.5% (95% CI 1.3–4.2%),
P=0.013]. The additional costs per quality-adjusted life year saved amounted to
39 388 (95% CI 16 731–49 329) during the start-up phase of the study and to 23
661 (95% CI 10 327–35 528) at steady state.
Conclusion Diffuse implementation of AEDs fully operated by trained volunteers
and laypersons within a broad and unselected environment proved safe and was
associated with a significantly higher long-term survival of CA victims.
Noise burden and
the risk of myocardial infarction
Eur Heart J 27: 276-282.
Stefan N. Willich, Karl Wegscheider,
Martina Stallmann and Thomas Keil
Aims Chronic noise exposure
is associated with adverse pathophysiological effects and may contribute to the
progression of cardiovascular disease. We, therefore, determined the risk of
noise for the incidence of myocardial infarction.
Methods and results In a case–control study, 4115 patients (3054 men, 56±9
years; 1061 women, 58±9 years) consecutively admitted to all 32 major hospitals
in Berlin with confirmed diagnosis of acute myocardial infarction were enrolled
from 1998 to 2001 in the Noise and Risk of Myocardial Infarction (NaRoMI) study.
Controls were matched for gender, age, and hospital. In standardized interviews,
information was obtained on environmental and work noise annoyance. The sound
levels of environmental and work noise were assessed using traffic noise maps as
proxy and international standards for workplaces, respectively. In multivariate
logistic regression models, the adjusted odds ratios of noise variables were
determined. There was a marginally increased risk of myocardial infarction
associated with annoyance by environmental noise in women (adjusted odds ratio
1.47, 95% confidence interval 0.95–2.25, P=0.081) but not in men, and not
associated with annoyance by work noise. Environmental sound levels were
associated with increased risk in men and women (odds ratios 1.46, 1.02–2.09,
P=0.040 and 3.36, 1.40–8.06, P=0.007) and work sound levels in men only (1.31,
1.01–1.70, P=0.045).
Conclusion Chronic noise burden is
associated with the risk of myocardial infarction. The risk increase appears
more closely associated with sound levels than with subjective annoyance.
Further investigation of the gender-related risk of noise exposure may aid in
improving prevention.
Left Atrionodal Connections in Typical and Atypical Atrioventricular Nodal
Reentrant Tachycardias: Activation Sequence in the Coronary Sinus and Results of
Radiofrequency Catheter Ablation
J Cardiovasc Electrophysiol, Vol.
17, pp. 171-177, March 2006
GI-BYOUNG NAM, M.D., KYOUNG-SUK RHEE,
M.D., JUN KIM, M.D., KEE-JOON CHOI, M.D., and YOU-HO KIM, M.D.
Introduction: The presence of
atrionodal connections and coronary sinus (CS) breakthrough in atrioventricular
nodal reentrant tachycardia (AVNRT) has been suggested. However, the incidence,
anatomic relationship with reentrant circuit, and results of catheter ablation
are unknown.
Methods and Results: Fifty-two patients with typical slow/fast AVNRT and 10
patients with atypical slow/intermediate or fast/slow AVNRT were included.
Eccentric activation of the CS (EACS) was observed in 3 of 52 patients with
typical and 8 of 10 patients with atypical AVNRT. The earliest CS activation in
patients with an EACS was recorded at a site 10–20 mm inside the CS ostium. The
postpacing interval after transient entrainment at the proximal CS in patients
with EACS was 23 ± 21 msec longer than the pacing cycle length. Modification or
ablation of the slow pathway was successful in all patients with typical
slow/fast AVNRT and in 7 of 9 patients with atypical AVNRT by RF energy
delivered at the right septal tricuspid annulus (TA). In 2 patients with
atypical AVNRT and an EACS, RF delivery inside the CS targeting the earliest CS
activation eliminated the sustained AVNRT.
Conclusion: Eccentric coronary sinus activation is observed in some rare cases
of typical AVNRT, and in a majority of atypical AVNRT. Entrainment results
suggest that the proximal coronary sinus may be part of the reentrant circuit.
RF ablation of atypical AVNRT, if it fails from the standard right-side
approach, can be targeted at the site of earliest retrograde atrial activation
inside the CS.
How many patients with heart failure are eligible for cardiac resynchronization?
Insights from two prospective cohorts
Eur Heart J 27: 323-329
Finlay A. McAlister, Jack V. Tu, Alice
Newman, Douglas S. Lee, Shane Kimber, Bibiana Cujec, and Paul W. Armstrong
Aims To determine what
proportion of patients with heart failure are eligible for cardiac
resynchronization therapy (CRT).
Methods and results Eligibility criteria from the trials establishing the
efficacy of CRT were applied to two prospective cohorts: the first enrolled
patients with newly diagnosed heart failure discharged from 103 hospitals
between April 1999 and March 2001 (‘the hospital discharge cohort’); the second
enrolled patients seen in a specialized clinic between August 2003 and January
2004 (‘the specialty clinic cohort’). In the hospital discharge cohort, 73
patients (3% of the 2640 patients with ischaemic or dilated cardiomyopathy and
1% of all 9096 patients with heart failure discharged alive) met trial
eligibility criteria: LVEF 0.35, QRS 120 ms, sinus rhythm, and NYHA class III or
IV symptoms despite the treatment with ACE-inhibitor/angiotensin receptor
blocker and beta-blocker. In the specialty clinic cohort, 54 patients (21% of
the 263 patients with ischaemic or dilated cardiomyopathy and 17% of all 309
patients with heart failure) met these criteria. If persistent symptoms despite
taking spironolactone were required for CRT eligibility, then the proportions
qualifying dropped to 1% in the hospital discharge cohort and 18% in the
specialty clinic cohort.
Conclusion Few heart failure patients
meet trial eligibility criteria for CRT.
Upgrade to biventricular pacing in patients with conventional pacemakers and
heart failure: a double-blind, randomized crossover study
Europace 8: 51-55
Carl J. Höijer, Carl Meurling and Johan
Brand
Methods and results Study
inclusion criteria were New York Heart Association (NYHA) classes III and IV,
dominant paced rhythm, and no left bundle branch block in the pre-pacing ECG.
Ten patients with pacemakers (four VVIR due to slow atrial fibrillation and six
DDDR, of which four were due to high-degree atrioventricular block and two to
sinus node disease) were upgraded to a biventricular pacing (BVP) system. The
median duration of pacing before the upgrade was 5.7 years. Assessments of 6-min
walk test, symptom score, brain natriuretic peptide (pro-BNP), and
echocardiography were made pre-operatively. After a run-in period of 1 month in
BVP following the upgrade, the patients were randomized to a 2-month period in
either BVP or right ventricular pacing (RVP), followed by 2 months in the other
mode, in a double-blind crossover fashion. After each period, the pre-operative
measurements were repeated. After study completion, patients were asked to
select their preferred period. The median 6-min walking distance was
significantly longer in BVP (400 m) vs. RVP (315 m), P=0.02. The symptom score
was also significantly better in BVP (P=0.005). Median pro-BNP was significantly
lower in BVP than in RVP, 3030 vs. 5064 ng/L (P=0.005). Six patients demanded an
early crossover in RVP but none in BVP (P=0.015), and all patients except one
expressed a preference for BVP. However, echo parameters did not show any
significant differences between BVP and RVP.
Conclusion Pacemaker patients with heart failure and dominant paced heart rhythm
benefit substantially from an upgrade to BVP, in terms of physical performance
and symptoms. The upgrade resulted in significantly improved cardiac function as
reflected by reduced levels of pro-BNP.
Use of a new cardiac pacing mode designed to eliminate unnecessary ventricular
pacing
Europace 8: 96-101
Gerd Fröhlig, Daniel Gras, Jacques Victor,
Philippe Mabo, Daniel Galley, Arnaud Savouré, Gaël Jauvert, Pascal Defaye,
Pascale Ducloux and Amel Amblard
Aims To examine the
performance of AAIsafeR2, a new pacing mode to minimize the cumulative
proportion of ventricular pacing in patients who do not need regular ventricular
support.
Methods and results The safety of AAIsafeR2 was examined in 123 recipients
(73±12 years old, 51% men) of dual chamber pacemakers implanted for sinus node
dysfunction, paroxysmal AV block or the bradycardia-tachycardia syndrome. Data
were collected from pacemaker diagnostics, and the first 43 patients underwent
24-h Holter recordings before being discharged from the hospital with AAIsafeR2
activated. No adverse event related to AAIsafeR2 was observed. All ventricular
pauses detected on Holter tapes triggered immediate back-up ventricular pacing.
Appropriate switches to DDD occurred in 97 of 123 patients. In 69 of 123 devices
(56%) switches to DDD were non-sustained, and the average % ventricular pacing
in this group was 0.2±0.5%.
Conclusion AAIsafeR2 mode seems to be
safe and reliable in patients with infrequent slowing or pauses in
ventricular activity, while maintaining ventricular pacing below 1%.
Long-term safety and efficacy of slow pathway ablation in patients with
atrioventricular nodal re-entrant tachycardia and pre-existing prolonged PR
interval
Europace 8: 129-133
Jean Luc Pasquié, Joseph Scalzi, Jean
Christophe Macia, Florence Leclercq and Robert Grolleau-Raoux
The association of
atrioventricular nodal re-entrant tachycardia (AVNRT) and pre-existing prolonged
PR interval is unusual. Radiofrequency (RF) ablation in such patients may be
associated with an increased risk of immediate and delayed AV block. The aim of
our study is to assess the long-term efficacy and safety of slow pathway
ablation in this population. We studied 10 patients (4 males and 6 females) with
pre-existing prolonged PR interval of 68 consecutive patients with AVNRT. All
had slow–fast subtype of AVNRT. The mean PR interval was 222±15 ms before RF.
The patients with pre-existing prolonged PR were older (69±15 vs. 54±17,
P=0.008) and their tachycardias were slower (387±102 vs. 323±73 ms; P<0.05).
Transient complete AV block (<5 s) occurred in two patients. None had permanent
complete AV block. One patient had a significant increase in PR interval (from
220 to 320 ms). The mean post-RF PR interval was 232±37 ms (P=n.s.). Over a mean
follow-up of 39±21 months, none had a recurrence of tachycardia nor developed
higher degree AV block. In conclusion, in patients with AVNRT and pre-existing
prolonged PR interval, a slow pathway ablation appeared efficient and safe. From
our data, no delayed AV block developed on a long follow-up. Most of the
patients with periprocedural transient AV block had no evidence of dual AV node
physiology, suggesting that, in this population, absence of dual AV node
physiology may be associated with a higher risk of AV block during slow pathway
ablation.
A Randomized Comparison of Permanent Septal Versus Apical Right Ventricular
Pacing: Short-Term Results
J Cardiovasc Electrophysiol, Vol.
17, pp. 238-242, March 2006
FREDERIC VICTOR, M.D., PH.D., PHILIPPE
MABO, M.D., HASSAN MANSOUR, M.D., DOMINIQUE PAVIN, M.D., GUILLAUME KABALU, M.D.,
CHRISTIAN DE PLACE, M.D., CHRISTOPHE LECLERCQ, M.D., PH.D., and J. CLAUDE
DAUBERT, M.D., F.A.C.C.
Objectives: This study
compared chronic right ventricular (RV) pacing at the septum versus apex.
Background: Chronic RV apical pacing may be detrimental to ventricular function.
This randomized, pilot study examined whether, compared with apical, permanent
septal pacing preserves cardiac function.
Methods: Ablation of the atrioventricular junction for permanent AF, followed by
implantation of a DDDR pacemaker connected to two ventricular leads was
performed in 28 patients. One lead screwed into the septum and another placed at
the apex were connected to the atrial and ventricular port, respectively. Septum
or apex was paced by programming AAIR or VVIR modes, respectively. Patients were
randomly assigned, 4 months later, to pacing at one site for 3 months, and
crossed over to the other for 3 months. New York Heart Association class, QRS
width and axis, left ventricular ejection fraction (LVEF), exercise duration,
and peak oxygen uptake were measured. Results in patients with LVEF >45% and
≤45% were compared.
Results: Septal pacing was associated with shorter QRS (145 ± 4 msec vs 170 ± 4
msec, P < 0.01) and normal axis (40°± 10° vs −71 ± 4°, P < 0.01). At 3 months,
among patients with baseline LVEF ≤45%, LVEF was 42 ± 5% after septal pacing
versus 37 ± 4% after apical pacing (P < 0.001).
Conclusion: In contrast to RV apical
pacing, chronic RV septal pacing preserved LVEF in patients with baseline LVEF
≤45%.
Population-Based Analysis of Sudden Cardiac Death With and Without Left
Ventricular Systolic Dysfunction
Two-Year Findings from the Oregon Sudden Unexpected Death Study
J Am Coll Cardiol 47: 1161-1166
Eric C. Stecker, MD, Catherine Vickers,
RN, Justin Waltz, MPH, Carmen Socoteanu, MD, Benjamin T. John, MD, Ronald
Mariani, EMT-P, John H. McAnulty, MD, FACC, Karen Gunson, MD, Jonathan Jui, MD,
MPH and Sumeet S. Chugh, MD, FACC
OBJECTIVES: We sought to
evaluate the contribution of left ventricular (LV) dysfunction toward occurrence
of sudden cardiac death (SCD) in the general population, and to identify
distinguishing characteristics of SCD in the absence of LV dysfunction.
BACKGROUND: Patients who manifest warning symptoms and signs are more likely to
undergo evaluation before SCD. Although prevalence of LV dysfunction in this
subgroup may overestimate the prevalence in overall SCD, this is the only means
of assessment in the general population.
METHODS: All cases of SCD in Multnomah County, Oregon (population 660,486; 2002
to 2004) were prospectively ascertained in the ongoing Oregon Sudden Unexpected
Death Study. We retrospectively assessed LV ejection fraction (LVEF) among
subjects who underwent evaluation of LV function before SCD (normal: 55%; mildly
to moderately reduced: 36% to 54%; and severely reduced: 35%). Of a total of 714
SCD cases (annual incidence 54 per 100,000), LV function was assessed in 121
(17%).
RESULTS: The LVEF was severely reduced
in 36 patients (30%), mildly to moderately reduced in 27 (22%), and normal in 58
(48%). Patients with normal LVEF were distinguishable by younger age (66
± 15 years vs. 74 ± 10 years; p = 0.001), higher proportion of females (47% vs.
27%; p = 0.025), higher prevalence of seizure disorder (14% vs. 0%; p = 0.002),
and lower prevalence of established coronary artery disease (50% vs. 81%; p <
0.001).
CONCLUSIONS: In this community-wide study,
only one-third of the evaluated SCD
cases had severe LV dysfunction meeting current criteria for prophylactic
cardioverter-defibrillator implantation. The SCD cases with normal LV
function had several distinguishing clinical characteristics. These findings
support the aggressive development of alternative screening methods to enhance
identification of patients at risk.
Fluoxetine vs. propranolol in the treatment of vasovagal syncope: a prospective,
randomized, placebo-controlled study
Europace 8: 193-198
George N. Theodorakis, Dionyssios
Leftheriotis, Efthimios G. Livanis, Panagiota Flevari, Georgia Karabela,
Nikolitsa Aggelopoulou and Dimitrios Th. Kremastinos
Aims To compare the
therapeutic efficacy of placebo, propranolol, and fluoxetine in patients with
vasovagal syncope (VVS).
Methods and results Ninety-six consecutive patients with VVS were randomized to
treatment with placebo, propranolol, or fluoxetine and followed-up for 6 months.
Before and during treatment, they reported their syncopal and presyncopal
episodes and graded their well-being, expressed as the general evaluation of
life, general activities, and everyday activities (each scaled from 1=very good
to 5=very bad). Two patients refused follow-up. Among the remaining 94, no
difference between groups was observed regarding the distribution of time of
vasovagal events (syncopes or presyncopes) during follow-up (log-rank test). No
difference was also observed when syncopes and presyncopes were assessed
separately. Eighteen patients discontinued therapy. Among the remaining 76
(‘on-treatment’ analysis), the mean time to a vasovagal episode (syncope or
presyncope) was significantly longer in the fluoxetine group when compared with
the two other groups (log-rank test, P<0.05). A significant difference in favour
of fluoxetine was also observed regarding presyncopes. The difference between
groups regarding the syncope-free period was not significant. During therapy,
patients' well-being was improved (decreased) only in the fluoxetine-group
(13.4±0.7 vs. 15.4±0.9 before treatment, P<0.01).
Conclusion Fluoxetine seems to be
equivalent to propranolol and placebo in the treatment of VVS.
However, it improves patients'
well-being and might be more effective in reducing presyncopes and total
vasovagal events in some patients with recurrent VVS.
Individualized Selection of Pacing Algorithms for the Prevention of Recurrent
Atrial Fibrillation: Results from the VIP Registry
PACE 2006; 29:124–134
THORSTEN LEWALTER, ALEXANDER YANG,
DIETRICH PFEIFFER, JAAP RUITER, GÖTZ SCHNITZLER, TILMANN MARKERT, MOGENS ASKLUND
, OLIVER PRZIBILLE, ARMIN WELZ, BAHMAN ESMAILZADEH, MARKUS LINHART, and BERNDT
LÜDERITZ
Objectives: The VIP registry
investigated the efficacy of preventive pacing algorithm selection in reducing
atrial fibrillation (AF) burden.
Background: There are few data identifying which patients might benefit most
from which preventive pacing algorithms.
Methods: Patients, with at least one documented AF episode and a conventional
antibradycardia indication for pacemaker therapy, were enrolled. They received
pacemakers with AF diagnostics and four preventive algorithms (Selection and
PreventAF series, Vitatron). A 3-month Diagnostic Phase with conventional pacing
identified a Substrate Group (>70% of AF episodes with <2 premature atrial
contractions [PACs] before AF onset) and a Trigger Group (≤70% of AF episodes
with <2 PACs before AF onset). This was followed by a 3-month Therapeutic Phase
where in the Trigger Group algorithms were enabled aimed at avoiding or
preventing a PAC and in the Substrate Group continuous atrial overdrive pacing
was enabled.
Results: One hundred and twenty-six patients were evaluated. In the Trigger
Group (n = 73), there was a statistically significant 28% improvement in AF
burden (median AF burden: 2.06 hours/day, Diagnostic Phase vs 1.49 hours/day,
Therapy Phase; P = 0.03304 signed-rank test), and reduced PAC activity. There
was no significant improvement in AF burden in the Substrate Group (median AF
burden: 1.82 hours/day, Diagnostic Phase vs 2.38 hours/day, Therapy Phase; P =
0.12095 signed-rank test), and little change in PAC activity.
Conclusions: We identified a subgroup of patients for whom the selection of
appropriate pacing algorithms, based on individual diagnostic data, translated
into a reduced AF burden. Trigger AF
patients were more likely responders to preventive pacing algorithms as a result
of PAC suppression.
Renal Insufficiency and the Risk of Infection from Pacemaker or Defibrillator
Surgery
PACE 2006; 29:142–145
HEATHER BLOOM, BRIAN HEEKE, ANGEL LEON,
FERNANDO MERA, DAVID DELURGIO, JOHN BESHAI, and JONATHAN LANGBERG
Background: Pacemakers and
implanted cardioverter defibrillator (ICD) infection rates are rising. Renal
insufficiency impairs immune function and is known to increase the risk of
infection following implantation of orthopedic hardware. The purpose of the
current study is to characterize the risk factors for pacemaker and ICD
infection and to evaluate the role of renal insufficiency in this complication.
Methods and Results: A large (n = 4,856) single center experience with pacemaker
and ICD procedures was reviewed. Of these, 141 were extractions of infected
devices and 76 of these patients had been implanted in the Emory system and had
preimplant creatinine information available for analysis. These cases were
compared to 76 control patients undergoing device implantation matched by date
of implant who had no infective complications. Demographic and clinical data
from both groups were compared using both univariate and multivariate analysis.
The overall rate of infection was 1.5%.
Patients with device infection were more likely to have congestive heart failure
(CHF), be diabetic, have generator exchanges, and to take warfarin than
controls. There was no difference in the prevalence of coronary disease,
atrial fibrillation, steroid use, or malignancy between the two groups. Elevated
creatinine (Cr ≥1.5 mg/dL) was much more frequent in patients with infection
than in controls (38% vs 12%, odds ratio 4.6, P < 0.001). Moderate to severe
renal disease (GFR ≤60 cc/min/1.73 m2) was the most potent risk factor for
infection, with a prevalence of 42% in infected patients versus 13% in controls
(odds ratio of 4.8).
Conclusions: Renal insufficiency dramatically increases the risk of infection
complicating pacemaker or ICD surgery. This association should be part of the
risk-benefit consideration prior to device implantation. Additional study of
more extensive perioperative antibiotic therapy in this subset of patients is
warranted.
Risks and benefits of omega 3 fats for mortality, cardiovascular disease, and
cancer: systematic review
BMJ, published 24 March 2006
Lee Hooper, Rachel L Thompson, Roger A
Harrison, Carolyn D Summerbell, Andy R Ness, Helen J Moore, Helen V
Worthington, Paul N Durrington, Julian P T Higgins, Nigel E Capps, Rudolph A
Riemersma, Shah B J Ebrahim, George Davey Smith
Objective To review
systematically the evidence for an effect of long chain and shorter chain omega
3 fatty acids on total mortality, cardiovascular events, and cancer.
Data sources Electronic databases searched to February 2002; authors contacted
and bibliographies of randomised controlled trials (RCTs) checked to locate
studies.
Review methods Review of RCTs of omega 3 intake for 6 months in adults (with or
without risk factors for cardiovascular disease) with data on a relevant
outcome. Cohort studies that estimated omega 3 intake and related this to
clinical outcome during at least 6 months were also included. Application of
inclusion criteria, data extraction, and quality assessments were performed
independently in duplicate.
Results Of 15 159 titles and abstracts assessed, 48 RCTs (36 913 participants)
and 41 cohort studies were analysed. The trial results were inconsistent. The
pooled estimate showed no strong evidence of reduced risk of total mortality
(relative risk 0.87, 95% confidence interval 0.73 to 1.03) or combined
cardiovascular events (0.95, 0.82 to 1.12) in participants taking additional
omega 3 fats. The few studies at low risk of bias were more consistent, but they
showed no effect of omega 3 on total mortality (0.98, 0.70 to 1.36) or
cardiovascular events (1.09, 0.87 to 1.37). When data from the subgroup of
studies of long chain omega 3 fats were analysed separately, total mortality
(0.86, 0.70 to 1.04; 138 events) and cardiovascular events (0.93, 0.79 to 1.11)
were not clearly reduced. Neither RCTs nor cohort studies suggested increased
risk of cancer with a higher intake of omega 3 (trials: 1.07, 0.88 to 1.30;
cohort studies: 1.02, 0.87 to 1.19), but clinically important harm could not be
excluded.
Conclusion Long chain and shorter chain omega 3 fats do not have a clear effect
on total mortality, combined cardiovascular events, or cancer.
Mending the rhythm does not improve prognosis in patients with persistent atrial
fibrillation: a subanalysis of the RACE study
Eur Heart J 27: 357-364.
Michiel Rienstra, Isabelle C. Van
Gelder, Vincent E. Hagens, Nic J.G.M. Veeger, Dirk J. Van Veldhuisen, Harry
J.G.M. Crijns for the RACE Investigators
Aims To compare outcome of AF
patients with effective rhythm control with patients treated with rate control.
Methods and results Out of
the 266 AF patients randomized to rhythm control in the RACE study, 49 patients
turned to long-term sinus rhythm and were continuously treated with oral
anticoagulation. The incidence of the primary endpoint in these patients was
compared to that in 178 patients out of the initial 256 rate-control patients of
RACE who were in AF and using oral anticoagulation continuously. Baseline
characteristics of both groups were not different. After a mean follow-up of
2.3±0.6 years, the primary endpoint (a composite of cardiovascular mortality,
heart failure, thrombo-embolic complications (TECs), bleeding, serious adverse
effects of antiarrhythmic drugs and pacemaker implants) was 22.4% in the
rhythm-control group vs. 15.2% in the rate-control group. Multivariable
regression analysis indicated coronary artery disease, heart failure, and
digitalis as independent risk indicators of cardiovascular morbidity and
mortality. Chronic sinus rhythm did not matter.
Conclusion Among patients who
remained on warfarin, those who mostly were maintained in sinus rhythm under a
rhythm-control strategy did not have a superior prognosis compared to those who
remained in AF under a rate-control strategy.
Epinephrine QT Stress Testing in the Evaluation of Congenital Long-QT Syndrome
Diagnostic Accuracy of the Paradoxical QT Response
Circulation. 2006;113:1385-1392
Himeshkumar Vyas, MD; Joseph Hejlik, RN;
Michael J. Ackerman, MD, PhD
Background— A paradoxical
increase in the uncorrected QT interval during infusion of low-dose epinephrine
appears pathognomonic for type 1 long-QT syndrome (LQT1). We sought to determine
the diagnostic accuracy of this response among patients referred for clinical
evaluation of congenital long-QT syndrome (LQTS).
Methods and Results— From 1999 to 2002, 147 genotyped patients (125 untreated
and 22 undergoing ß-blocker therapy) had an epinephrine QT stress test that
involved a 25-minute infusion protocol (0.025 to 0.3 µg • kg–1 • min–1). A
12-lead ECG was monitored continuously, and repolarization parameters were
measured. The sensitivity, specificity, and positive and negative predictive
values for the paradoxical QT response (defined as a 30-ms increase in QT during
infusion of 0.1 µg • kg–1 • min–1 epinephrine) was determined. The 125 untreated
patients (44 genotype negative, 40 LQT1, 30 LQT2, and 11 LQT3) constituted the
primary analysis. The median baseline corrected QT intervals (QTc) were 444 ms
(gene negative), 456 ms (LQT1), 486 ms (LQT2), and 473 ms (LQT3). The median
change in QT interval during low-dose epinephrine infusion was –23 ms in the
gene-negative group, 78 ms in LQT1, –4 ms in LQT2, and –58 ms in LQT3. The
paradoxical QT response was observed in 37 (92%) of 40 patients with LQT1
compared with 18% (gene-negative), 13% (LQT2), and 0% (LQT3; P<0.0001) of the
remaining patients. Overall, the paradoxical QT response had a sensitivity of
92.5%, specificity of 86%, positive predictive value of 76%, and negative
predictive value of 96% for LQT1 status. Secondary analysis of the subset
undergoing ß-blocker therapy indicated inferior diagnostic utility in this
setting.
Conclusions— The epinephrine QT stress test can unmask concealed type 1 LQTS
with a high level of accuracy.
Prevention of Syncope Trial (POST). A Randomized, Placebo-Controlled Study of
Metoprolol in the Prevention of Vasovagal Syncope
Circulation. 2006;113:1164-1170
Robert Sheldon MD, PhD, Stuart Connolly MD, Sarah Rose PhD, Thomas Klingenheben
MD, Andrew Krahn MD, Carlos Morillo MD, Mario Talajic MD, Teresa Ku MD, Fetnat
Fouad-Tarazi MD, Debbie Ritchie MN, Mary-Lou Koshman RN, for the POST
Investigators
Background--Previous studies that assessed the effects of -blockers in
preventing vasovagal syncope provided mixed results. Our goal was to determine
whether treatment with metoprolol reduces the risk of syncope in patients with
vasovagal syncope.
Methods and Results--The multicenter Prevention of Syncope Trial (POST) was a
randomized, placebo-controlled, double-blind, trial designed to assess the
effects of metoprolol in vasovagal syncope over a 1-year treatment period. Two
prespecified analyses included the relationships of age and initial tilt-test
results to any benefit from metoprolol. All patients had >2 syncopal spells and
a positive tilt test. Randomization was stratified according to ages <42 and 42
years. Patients received either metoprolol or matching placebo at
highest-tolerated doses from 25 to 200 mg daily. The main outcome measure was
the first recurrence of syncope. A total of 208 patients (mean age 42±18 years)
with a median of 9 syncopal spells over a median of 11 years were randomized,
108 to receive metoprolol and 100 to the placebo group. There were 75 patients
with 1 recurrence of syncope. The likelihood of recurrent syncope was not
significantly different between groups. Neither the age of the patient nor the
need for isoproterenol to produce a positive tilt test predicted subsequent
significant benefit from metoprolol.
Conclusions--Metoprolol was not effective in preventing vasovagal syncope in the
study population.
Amiodarone Is Poorly Effective
for the Acute Termination of Ventricular Tachycardia
Annals of Emergency Medicine
Volume 47, Issue 3 , March 2006, Pages 217-224
Keith A. Marill MD, Ian S.
deSouza MD, Daniel K. Nishijima MD, Thomas O. Stair MD, Gary S. Setnik MD and
Jeremy N. Ruskin MD
Study objective It is
hypothesized that intravenous (IV) amiodarone is poorly effective for the acute
termination of sustained monomorphic ventricular tachycardia because of the
relatively slow onset of its Vaughn-Williams class III effect to prolong
myocardial depolarization and the refractory period. This study is designed to
determine the effectiveness and safety of IV amiodarone for the termination of
sustained monomorphic ventricular tachycardia.
Methods A retrospective case series was collected at 4 urban
university-affiliated hospitals from September 1996 to April 2005 after
institutional review board approval with waiver of informed consent. Emergency
department (ED) patients treated with IV amiodarone for ventricular tachycardia
were identified by ED treatment and hospital pharmacy billing records,
International Classification of Diseases, Ninth Revision discharge codes, and
ECG characteristics. All consecutive patients who received at least 150 mg
amiodarone in 15 minutes or less for spontaneous sustained monomorphic
ventricular tachycardia were eligible for inclusion. Sustained monomorphic
ventricular tachycardia was defined as a tachycardia with uninterrupted duration
or rapid recurrence despite automatic internal cardiac defibrillator therapy for
at least 5 minutes before amiodarone treatment, monomorphic morphology, rate
greater than 120 beats/min, QRS duration greater than 120 ms, and subsequently
determined to be ventricular tachycardia by ECG criteria (eg, atrioventricular
dissociation), implanted device interrogation, or formal electrophysiology
study. Measured outcomes included sustained termination of ventricular
tachycardia within 20 minutes of initiation of amiodarone infusion and any
documented adverse effects. Rates of successful termination and adverse effects
and their 95% confidence intervals (CIs) were calculated. The presence or
average values of potentially confounding predictors in patients with and
without ventricular tachycardia termination after amiodarone were also
calculated and compared.
Results Thirty-three patients were identified and included. Five patients
received electrical therapy within 20 minutes of initiation of amiodarone
infusion, and the response to amiodarone was unknown. Twenty-seven of the
remaining 28 patients received 150 mg amiodarone, and the rate of successful
ventricular tachycardia termination was 8 of 28, 29% (95% CI 13 to 49). Two of
33 patients, 6% (95% CI 1 to 20), required direct current cardioversion for
presyncope or hypotension temporally associated with amiodarone treatment.
Conclusion IV amiodarone, as currently administered, is relatively safe but
ineffective for the acute termination of sustained ventricular tachycardia.
Cryoablation for accessory pathways located near normal conduction tissues or
within the coronary venous system in children and young adults
Heart Rhythm, Volume 3, Issue
3, Pages 253-258 (March 2006)
Yaniv Bar-Cohen, MD, Frank
Cecchin, MD, Mark E. Alexander, MD, Charles I. Berul, MD, John K. Triedman, MD,
Edward P. Walsh, MD
Background Cryoablation may
offer advantages over radiofrequency (RF) ablation for certain arrhythmia
substrates, such as septal accessory pathways (APs). Data for young patients,
especially regarding recurrence risk, require expansion.
Objectives The purpose of this study was to study institutional outcomes for
cryoablation of APs located in potentially difficult septal regions for children
and young adults.
Methods Cryoablation was attempted in 35 young patients (mean age 15.6 years)
with 37 APs that were either close to normal conduction tissues or inside the
coronary venous system. Outcomes were compared with previously published
institutional data for RF ablation at these same locations.
Results Acute cryoablation success was achieved for 29 (78%) of 37 APs. Apart
from permanent PR prolongation in one case and right bundle branch block in one
other, there were no detrimental effects on normal conduction. At median
follow-up of 207 days (range 2–695 days), AP conduction recurred for 13 (45%) of
29 ablated APs. Younger patient age and midseptal AP location correlated with
higher likelihood of recurrence. Acute success rates for cryoablation were
similar to RF ablation in our laboratory, but recurrence rates were
significantly higher (P <.001).
Conclusion Cryoablation yields acute success rates comparable with RF ablation
for difficult septal APs in young patients. The risk of AP recurrence appears
higher after cryoablation, although safety benefits may provide suitable
compensation for this deficiency. Methods for creating more effective
cryoablation lesions need to be explored.
An Implantable Loop Recorder
Study of Highly Symptomatic Vasovagal Patients: The Heart Rhythm Observed During
a Spontaneous Syncope Is Identical to the Recurrent Syncope But Not Correlated
With the Head-Up Tilt Test or Adenosine Triphosphate Test
J Am Coll Cardiol 47: 587-593
Jean-Claude Deharo, MD,
Christophe Jego, MD, André Lanteaume, MD and Pierre Djiane, MD
OBJECTIVES: The aim of this
study was to analyze the heart rhythm during spontaneous vasovagal syncope (VVS)
in highly symptomatic patients with implantable loop recorders (ILR) and to
correlate this rhythm with the heart rhythm observed during head-up tilt test
(HUT).
BACKGROUND: Heart rhythm obtained during provocative condition is often used to
guide therapy in VVS. To date there is no conclusive evidence that the heart
rhythm observed during a positive HUT can predict heart rhythm during VVS or
that the heart rhythm observed during a spontaneous syncope will be identical to
the recurrent syncope.
METHODS: Twenty-five consecutive VVS patients (age 60.2 ± 17.1 years; 14 women,)
presenting with frequent syncopes (6.9 ± 4.6 episodes/year) and a positive HUT
(cardioinhibitory in 8 patients) were implanted with an ILR. Seven of them also
had a positive adenosine triphosphate (ATP) test.
RESULTS: Follow-up was 17.0 ± 3.6 months. Thirty VVS were observed in 12
patients. Nine episodes showed bradycardia of <40 beats/min or asystole;
progressive sinus bradycardia preceding sinus arrest was the most frequent
electrocardiographic finding. Twenty-one syncopes occurred without severe
bradycardia. The heart rhythm observed during the first syncope was identical to
the recurrence. No correlation was found between slow heart rate at the ILR
interrogation and a cardioinhibitory HUT response (p = 1.0) or a positive ATP
test (p = 1.0).
CONCLUSIONS: In highly symptomatic patients with VVS,
the heart rhythm observed
during spontaneous syncope does not correlate with the HUT.
The heart rhythm
during the first spontaneous syncope is identical to the recurrent syncope.
Radiofrequency ablation of atrioventricular nodal reentrant tachycardia using a
novel magnetic guidance system compared with a conventional approach
Heart Rhythm, Volume 3, Issue
3, Pages 261-267 (March 2006)
Roger Kerzner, MD, José
Mauricio Sánchez, MD, Judy L. Osborn, RN, Jane Chen, MD, Mitchell N. Faddis, MD,
PhD, Marye J. Gleva, MD, Bruce D. Lindsay, MD, Timothy W. Smith, DPhil, MD
Background A novel magnetic
guidance system has been developed that allows the operator to remotely navigate
an electrophysiology mapping/ablation catheter to precise locations in the heart
for treatment of tachyarrhythmias. To date, this new technology has not been
directly compared with the conventional approach.
Objective To compare the use of the magnetic guidance system to the conventional
approach for ablation of atrioventricular nodal reentry tachycardia.
Methods Between November 2002 and October 2004, 28 patients with
atrioventricular nodal reentry tachycardia treated with the magnetic guidance
system were retrospectively compared with 28 matched control patients.
Results Patients treated using the magnetic guidance system had similar
procedure durations and fluoroscopy times compared with the matched controls.
The only statistically significant difference between the groups was a longer
time between insertion of the ablation catheter and placement of the first
radiofrequency lesion in the magnetic guidance system cohort (23.3 ± 12.0 vs.
10.5 ± 13.9, p=0.001), possibly due to the research protocol. However, there was
a trend toward a shorter total time that radiofrequency energy was applied in
the magnetic guidance system cohort (5.2 ± 4.5 vs. 8.0 ± 7.2, p=0.087). There
were no major complications or recurrences after at least 3 months of follow-up
among the patients treated with the magnetic guidance system.
Conclusion The magnetic guidance system appears to have similar, and possibly
improved, clinical efficacy compared with conventional catheter navigation for
the treatment of atrioventricular nodal reentrant tachycardia.
Reduction in Ventricular
Tachyarrhythmias With Statins in the Multicenter Automatic Defibrillator
Implantation Trial (MADIT)-II
J Am Coll Cardiol 47: 769-773
Anant K. Vyas, MD, MPH,
Hongsheng Guo, MD, Arthur J. Moss, MD, Brian Olshansky, MD, Scott A. McNitt, MS,
W. Jackson Hall, PhD, Wojciech Zareba, MD, PhD, Jonathan S. Steinberg, MD, Avi
Fischer, MD, Jeremy Ruskin, MD, Mark L. Andrews, BBA for the MADIT-II Research
Group
OBJECTIVES: We evaluated
whether statins have anti-arrhythmic effects by exploring the association of
statin use with appropriate implantable cardioverter-defibrillator (ICD) therapy
for ventricular tachycardia/ventricular fibrillation (VT/VF) in the Multicenter
Automatic Defibrillator Implantation Trial (MADIT)-II.
BACKGROUND: A few studies have suggested that lipid-lowering drugs may have
anti-arrhythmic effects in patients with coronary artery disease.
METHODS: Patients receiving an ICD (n = 654; U.S. centers only) in the MADIT-II
study were categorized by the percentage of days each patient received statins
during follow-up (90% to 100%, n = 386; 11% to 89%, n = 116; and 0% to 10%, n =
152). The Kaplan-Meier method with significance testing by the log-rank
statistic and time-dependent proportional hazards regression analysis were used
to evaluate the effect of statin use on the probability of ICD therapy for the
combined end point VT/VF or cardiac death and for the end point VT/VF.
RESULTS: The cumulative rate of ICD therapy for VT/VF or cardiac death,
whichever occurred first, was significantly reduced in those with 90% statin
usage compared to those with lower statin usage (p = 0.01). The time-dependent
statin:no statin therapy hazard ratio was 0.65 (p < 0.01) for the end point of
VT/VF or cardiac death and 0.72 (p = 0.046) for VT/VF after adjusting for
relevant covariates.
CONCLUSIONS: Statin use in patients with an ICD was associated with a reduction
in the risk of cardiac death or VT/VF, whichever occurred first, and was
associated with a reduction in VT/VF episodes. These findings suggest that
statins have anti-arrhythmic properties.
Prognostic significance of
serum cholesterol levels in patients with idiopathic dilated cardiomyopathy
Eur Heart J 27: 691-699
Michael Christ, Theresia Klima,
Wolfram Grimm, Hans-Helge Mueller and Bernhard Maisch
Aims Previous studies indicate
that low cholesterol levels are associated with adverse prognosis in heart
failure patients, because elevated lipoprotein levels may negate bacterial
endotoxin load induced by gastrointestinal congestion.
Methods and results We examined the prognostic significance of lipid levels in a
cohort of 422 patients with idiopathic dilated cardiomyopathy (iDCM) [50±12
years, 342 males, 80 females, left ventricular ejection fraction (LV-EF):
31.6±10.6%]. During 42 months of follow-up, 86 patients (20.3%) died or received
a heart transplant. In univariate Cox regression analysis, reduced LV-EF, high
New York Heart Association (NYHA) class, and increased LV end-diastolic diameter
(LVEDD) were strong risk factors associated with that endpoint, whereas
decreased total cholesterol, HDL-cholesterol, and apoprotein I levels were
identified as weak risk predictors. After step-wise multivariable analysis, only
LVEDD, NYHA class, and LV-EF emerged as parameters independently contributing to
the model predicting risk for death or heart transplantation (P<0.05).
Cholesterol levels were positively associated with LV-EF and negatively
associated with LVEDD (P<0.05). Circulating sCD14 levels, a marker of endotoxin
exposure, were related to cholesterol levels (P<0.05) and LV-EF (P<0.05).
Conclusion Decreased cholesterol levels do not independently predict adverse
prognosis in patients with iDCM. Our findings indicate that low cholesterol
levels are dependent on the severity of cardiac disease.
Association of QRS duration and outcomes after myocardial infarction: the
VALIANT trial
Heart Rhythm, Volume 3, Issue
3, Pages 313-316 (March 2006)
Lakshminarayan Yerra, MD,
Nagesh Anavekar, MD, Hicham Skali, MD, Steve Zelenkofske, DO, Eric Velazquez,
MD, John McMurray, MD, Marc Pfeffer, MD, PhD, Scott D. Solomon, MD
Background Prolongation of the
QRS duration has been shown to be associated with adverse outcomes among heart
failure (HF) patients. The association of QRS duration with clinical outcomes in
the post–myocardial infarction (MI) setting is less well defined.
Objectives To assess the prognostic significance of QRS duration prolongation on
initial eletrocardiogram after acute MI.
Methods QRS duration was measured in 403 patients with MI complicated by left
ventricular dysfunction, signs or symptoms of HF, or both, who were enrolled in
the Valsartan in Acute Myocardial Infarction (VALIANT) echo study. The cohort
was divided into quartiles of QRS duration (<75 ms, 75–88 ms, 89–108 ms, >108
ms). The number of clinical events were determined and compared across the
groups.
Results Increasing QRS duration is associated with a higher incidence of HF,
sudden death (SD), and cardovascular (CV) death (P-trend <0.05) but not with
stroke or recurrent MI. The univariate relative risks for HF, SD, and CV death
with increasing QRS duration quartiles were 1.31 (95% CI, 1.06–1.64), 1.57 (95%
CI, 1.03–2.40), and 1.31 (95% CI, 1.03–1.66), respectively, but QRS duration did
not remain independently predictive of adverse outcome after adjusting for the
10 most predictive baseline covariates. Baseline end-diastolic and end-systolic
volumes were larger and ejection fraction was lower in the higher QRS quartile
groups.
Conclusions Prolonged QRS duration, even within the normal range, is associated
with larger ventricular volumes, reduced systolic function, and an increased
risk for development of HF, SD, and CV death after MI but appears to be a
marker, rather than an independent predictor, for increased risk.
Clinical predictors and
prognostic significance of electrical storm in patients with implantable
cardioverter defibrillators
Eur Heart J 27: 700-707
François Brigadeau, Claude
Kouakam, Didier Klug, Christelle Marquié, Alain Duhamel, Frédérique
Mizon-Gérard1, Dominique Lacroix and Salem Kacet
Aims Insufficient data exists
regarding predictors of electrical storms (ES) and clinical outcome in patients
treated with an implantable cardioverter defibrillator (ICD). The purpose of
this study was to delineate a subgroup of patients likely to experience ES and
to determine the impact of ES on mortality in ICD recipients.
Methods and results Baseline characteristics of 307 ICD-treated patients were
retrospectively analysed. ES was defined as two or more ventricular
tachyarrhythmias within 24 h leading to an immediate electrical therapy
(antitachycardia pacing and/or shock), separated by a period of sinus rhythm.
Clinical characteristics and survival of 123 patients experiencing a total of
294 episodes of ES (median 2 ES/patient, range 1–9), were compared with those of
184 ES-free patients during a median follow-up of 826 days (inter-quartile 1141
days). Median actuarial duration for the first ES occurrence after ICD implant
was 1417 days [95% confidence interval (CI) 1061–2363] with a median follow-up
of 816 days (7–4642 days) in ES-free patients. Univariate analysis identified
older age, depressed left ventricular ejection fraction (LVEF), ventricular
tachycardia (VT) as index arrhythmia, chronic renal failure and absence of
lipid-lowering drugs as variables significantly associated with an increased
risk of ES. Multivariable Cox analysis confirmed an independent predictive value
for chronic renal failure [hazard ratio (HR) 1.54, 95% CI 0.95–2.51, P=0.052],
VT (HR 2.20, 95% CI 1.44–3.37, P=0.0003), and LVEF (HR 0.98, 95% CI 0.97–0.99,
P=0.027). In contrast, diabetics (HR 0.49, 95% CI 0.27–0.90, P=0.022) were less
affected by ES. There was no difference in survival between both groups.
Conclusion ES is frequent but does not increase mortality in ICD's recipients.
Patients with severe systolic dysfunction, chronic renal failure and VT as
initial arrhythmia are likely to experience ES. Diabetics are less affected by
ES.
Safety of Sports Participation in Patients with Implantable Cardioverter
Defibrillators: A Survey of Heart Rhythm Society Members
Journal of Cardiovascular
Electrophysiology Volume 17 Page 11 - January 2006
RACHEL LAMPERT, M.D., DAVID CANNOM, M.D.,
and BRIAN OLSHANSKY, M.D.
Introduction: The safety of
sports participation for patients with implantable cardioverter defibrillators
(ICDs) is unknown, and recommendations among physicians may vary widely. The
purposes of this study were to determine current practice among patients with
ICDs and their physicians regarding sports participation, and to determine how
many physicians have cared for patients who have sustained adverse events during
sports participation.
Methods and Results: A survey was mailed to all 1,687 U.S. physician members of
the Heart Rhythm Society. Among 614 respondent physicians, recommendations
varied widely. Only 10% recommended avoidance of all sports more vigorous than
golf. Seventy-six percent recommended avoidance of contact, and 45% recommend
avoidance of competitive sports. Most (71%) based restrictions on patients'
underlying heart disease. Regardless of recommendations, most physicians (71%)
reported caring for patients who participated in sports, including many citing
vigorous, competitive sports, most commonly cited were basketball, running, and
skiing. ICD shocks during sports were common, cited by 40% of physicians.
However, few adverse consequences were reported. One percent of physicians
reported known injury to patient (all but 3 minor); 5%, injury to the ICD
system, and <1%, failure of shocks to terminate arrhythmia. The most common
adverse event reported was lead damage attributed to repetitive-motion
activities, most commonly weightlifting and golf.
Conclusions: Physician recommendations for sports participation for patients
with ICDs varies widely. Many patients with ICDs do participate in vigorous and
even competitive sports. While shocks
were common, significant adverse events were rare.
Are β-blockers needed in patients receiving spironolactone for severe chronic
heart failure? An analysis of the COPERNICUS study
Am Heart Journal Volume 151,
Issue 1, Pages 55-61 (January 2006)
Henry Kruma , Paul Mohacsib, Hugo A.
Katusc, Michael Tenderad, Jean-Lucien Rouleaue, Michael B. Fowlerf, Andrew J.
Coatsg, Ellen B. Roeckerh, Milton Packeri
Background The beneficial
effects of β-blockers and aldosterone receptor antagonists are now well
established in patients with severe systolic chronic heart failure (CHF).
However, it is unclear whether β-blockers are able to provide additional benefit
in patients already receiving aldosterone antagonists. We therefore examined
this question in the COPERNICUS study of 2289 patients with severe CHF receiving
the β1–β2/α1 blocker carvedilol compared with placebo.
Methods Patients were divided post hoc into subgroups according to whether they
were receiving spironolactone (n = 445) or not (n = 1844) at baseline.
Consistency of the effect of carvedilol versus placebo was examined for these
subgroups with respect to the predefined end points of all-cause mortality,
death or CHF-related hospitalizations, death or cardiovascular hospitalizations,
and death or all-cause hospitalizations.
Results The beneficial effect of carvedilol was similar among patients who were
or were not receiving spironolactone for each of the 4 efficacy measures. For
all-cause mortality, the Cox model hazard ratio for carvedilol compared with
placebo was 0.65 (95% CI 0.36-1.15) in patients receiving spironolactone and
0.65 (0.51-0.83) in patients not receiving spironolactone. Hazard ratios for
death or all-cause hospitalization were 0.76 (0.55-1.05) versus 0.76
(0.66-0.88); for death or cardiovascular hospitalization, 0.61 (0.42-0.89)
versus 0.75 (0.64-0.88); and for death or CHF hospitalization, 0.63 (0.43-0.94)
versus 0.70 (0.59-0.84), in patients receiving and not receiving spironolactone,
respectively. The safety and tolerability of treatment with carvedilol were also
similar, regardless of background spironolactone.
Conclusion Carvedilol remained clinically efficacious in the COPERNICUS study of
patients with severe CHF when added to background spironolactone in patients who
were practically all receiving angiotensin-converting enzyme inhibitor (or
angiotensin II antagonist) therapy. Therefore,
the use of spironolactone in patients
with severe CHF does not obviate the necessity of additional treatment that
interferes with the adverse effects of sympathetic activation, specifically
β-blockade.
Age of First Faint in Patients with Vasovagal
Syncope
Journal of Cardiovascular
Electrophysiology Volume 17 Page 49 - January 2006
ROBERT S. SHELDON, M.D. PH.D., AARON G.
SHELDON, B.SC., STUART J. CONNOLLY, M.D., CARLOS A. MORILLO, M.D., THOMAS
KLINGENHEBEN, M.D., ANDREW D. KRAHN, M.D., MARY-LOU KOSHMAN, R.N., and DEBBIE
RITCHIE, M.N., FOR THE INVESTIGATORS OF THE SYNCOPE SYMPTOM STUDY AND THE
PREVENTION OF SYNCOPE TRIAL
Introduction: Understanding
whether vasovagal syncope is a lifelong disorder might shed insight into its
physiology and affect management strategies. Accordingly, we determined the age
of the first syncopal spell in adult patients who sought care for syncope.
Methods and Results: Patients were 42 ± 18 years old with 64% women. They had
had a median 8 syncope spells (interquartile range [IQR]: 4, 20) with a median
frequency of 1.0 syncopal spells per year. The range of syncopal spells was
1–3,375, and the range of duration of history of syncope was 0.003–70 years. The
first syncopal spell occurred at ages 0–81 in a skewed distribution, with a
marked mode age of 13 years, a median age of 18 years (IQR 12, 37), and a mean
age of 26 ± 20 years. The distributions were statistically indistinguishable
across countries (P = 0.50), among Canadian regions (P = 0.69), and between the
studies (P = 0.49). The same modal values were seen in males and females, and in
patients <40 and ≥40 years old. However, patients ≥40 years had median ages of
onset older than patients <40 years (36 ± 23 vs 17 ± 8 years). Patients had a
recalled history of syncopal spells of median duration of 10 years (IQR: 2, 23),
with a range of 0.003–70 years. An age of onset <44 years was 86% accurate for
vasovagal syncope.
Conclusion: The most common age at which
vasovagal syncope first presents is 13 years, and patients remain at risk
of syncope for many years. Lifelong coping strategies may be desirable.
Frequency of Spontaneous and Inducible Atrioventricular Nodal Reentry
Tachycardia in Patients with Idiopathic Outflow Tract Ventricular Arrhythmias
Pacing and Clinical
Electrophysiology Volume 29 Page 21 - January 2006
IAN TOPILSKI, AHARON GLICK, SAMI VISKIN,
and BERNARD BELHASSEN
Objectives: We sought to
assess the frequency of spontaneous or inducible atrioventricular nodal reentry
tachycardia (AVNRT) in patients referred for radiofrequency ablation (RFA) of
idiopathic outflow tract ventricular arrhythmias.
Background: In patients with no obvious heart disease, AVNRT and outflow tract
ventricular tachycardia (VT) are the most frequently encountered
supraventricular and ventricular tachycardias, respectively. An increased
coexistence of the two arrhythmias has been recently suggested.
Methods: In 68 consecutive patients referred for RFA of an idiopathic
ventricular outflow tract arrhythmia, a stimulation protocol including repeated
bursts of rapid atrial pacing, up to triple atrial extrastimuli during sinus
rhythm and rapid ventricular pacing was performed before and after isoproterenol
infusion following RFA of the ventricular arrhythmia. In patients with inducible
AVNRT, RFA of the slow pathway was performed.
Results: Of the 68 study patients, 17 (25%) had either spontaneous AVNRT
documented prior to RFA of the ventricular arrhythmia (n = 4) or inducible AVNRT
at the time of RFA of the ventricular arrhythmia (n = 13). AVNRT was induced by
atrial pacing in 15 (88%) of 17 patients: in 3 patients without isoproterenol
and in 12 patients during isoproterenol infusion. Uncomplicated RFA of the slow
pathway was successfully achieved in all patients with inducible AVNRT.
Conclusion: Spontaneous or inducible AVNRT is relatively common in patients with
idiopathic outflow tract ventricular arrhythmias. Atrial stimulation, especially
when performed after isoproterenol infusion plays a major role in AVNRT
inducibility. Although we performed RFA of the slow pathway in patients with
inducible AVNRT and no prior tachycardia documentation, the question whether
this is mandatory remains unsettled.
Physiologic Pacing in Patients With Obstructive Sleep Apnea A Prospective,
Randomized Crossover Trial
J Am Coll Cardiol 2006, 47:
379-383
Andrew D. Krahn, MD, Raymond Yee, MD, Mark
K. Erickson, BSc, Toby Markowitz, BSEE, Lorne J. Gula, MD, George J. Klein, MD,
Allan C. Skanes, MD, Charles F.P. George, MD and Kathleen A. Ferguson, MD
OBJECTIVES: This study was
designed to assess the impact of prevention of bradycardia with physiologic
pacing on the severity of obstructive sleep apnea.
BACKGROUND: Apneic episodes during sleep are associated with slowing of the
heart rate during apnea and tachycardia with subsequent arousal. Patients with
permanent pacemakers may have reduced episodes of sleep apnea when their
pacemaker rate is set faster than their spontaneous nocturnal heart rate.
METHODS: We conducted a prospective, randomized, single-blind crossover trial of
temporary atrial pacing in obstructive sleep apnea to reduce the apnea hypopnea
index (AHI). Fifteen patients (age 60 ± 13 years, 12 men) with moderate to
severe obstructive sleep apnea (AHI 34 ± 14) underwent insertion of an
externalized atrial permanent pacing system via the left subclavian vein.
Patients underwent overnight respiratory sleep studies in hospital, during
atrial pacing at 75 beats/min, and with pacing turned off. The order of pacing
mode was randomized, with crossover the subsequent night to the other mode.
Patients were blinded to pacing mode, and the analysis of sleep recordings was
blind to pacing mode.
RESULTS: Pacing was tolerated without complications in all patients. Overnight
physiologic pacing did not affect the AHI (pacing 39 ± 21/h vs. control 42 ±
21/h, p = 0.23, 95% confidence interval –9.3 to 2.5 for difference),
desaturation time (pacing 3.8 ± 6.0% vs. control 3.5 ± 4.3%, p = 0.70), or the
minimum SaO2 (pacing 75 ± 10% vs. control 77 ± 11%, p = 0.38). There was a
borderline significant reduction in circulatory time with pacing (pacing 23.4 ±
3.2 s vs. control 25.5 ± 4.4 s, p = 0.09).
CONCLUSIONS: Temporary atrial pacing
does not appear to improve respiratory manifestations of obstructive sleep
apnea. Permanent atrial pacing in this patient population does not appear
to be justified.
Antibiotic Prophylaxis with a Single Dose of
Cefazolin During Pacemaker Implantation: Incidence of Long-Term Infective
Complications
Pacing and Clinical
Electrophysiology Volume 29 Page 29 - January 2006
EMANUELE BERTAGLIA, FRANCESCA ZERBO,
SUSANNA ZARDO, DANIELA BARZAN, FRANCO ZOPPO, and PIETRO PASCOTTO
Objective: Systemic and
localized infections related to permanent pacemaker implantation are not common,
but are serious and potentially life-threatening complications. The aims of this
prospective observational study were: (1) to assess the safety and long-term
efficacy of a simplified scheme of antibiotic prophylaxis, and (2) to identify
the predictors of long-term infective complications, in patients undergoing
pacemaker implantation or replacement.
Methods and Results: From October 1998 to July 2001, 852 patients (mean age 77.0
± 9.2 years; 474 men) who underwent new permanent pacemaker implantation (69.6%)
or pulse generator replacement (30.4%) received a mini-bag of 2 g of cefazolin
diluted in 50 mL of saline solution, administered intravenously in 20 minutes
before the beginning of the procedure. Early (within 2 months of implantation)
and late major and minor infective complications were recorded. During the
earlier phase, minor complications were observed in 9 patients (1%). During the
long-term phase of the surveillance (mean 25.6 ± 11.0 months, range 12–55
months) major infective complications were observed in 6 patients (0.7%). On
multivariate analysis, no clinical or procedural variable predicted the
occurrence of long-term infective complications.
Conclusions: Our data indicate the safety and efficacy of a single, intravenous
2 g dose of cefazolin in preventing infective complications related to pacemaker
implantation or replacement. No clinical or procedural variable predicted the
occurrence of long-term infective complications.
Patent Foramen Ovale: Innocent or Guilty? Evidence From a Prospective
Population-Based Study
J Am Coll Cardiol 2006, 47:
440-445
Irene Meissner, MD, Bijoy K. Khandheria,
MD , John A. Heit, MD, George W. Petty, MD, Sheldon G. Sheps, MD, Gary L.
Schwartz, MD, Jack P. Whisnant, MD, David O. Wiebers, MD, Jody L. Covalt, Tanya
M. Petterson, Teresa J.H. Christianson and Yoram Agmon, MD
OBJECTIVES: We sought to
determine the association between patent foramen ovale (PFO), atrial septal
aneurysm (ASA), and stroke prospectively in a unselected population sample.
BACKGROUND: The disputed relationship between PFO and stroke reflects
methodologic weaknesses in studies using invalid controls, unblinded
transesophageal echocardiography examinations, and data that are unadjusted for
age or comorbidity.
METHODS: The use of transesophageal echocardiography to identify PFO was
performed by a single echocardiographer using standardized definitions in 585
randomly sampled, Olmsted County (Minnesota) subjects age 45 years or older
participating in the Stroke Prevention: Assessment of Risk in a Community (SPARC)
study.
RESULTS: A PFO was identified in 140 (24.3%) subjects and ASA in 11 (1.9%)
subjects. Of the 140 subjects with PFO, 6 (4.3%) had an ASA; of the 437 subjects
without PFO, 5 had an ASA (1.1%, two-sided Fisher exact test, p = 0.028). During
a median follow-up of 5.1 years, cerebrovascular events (cerebrovascular
disease-related death, ischemic stroke, transient ischemic attack) occurred in
41 subjects. After adjustment for age and comorbidity, PFO was not a significant
independent predictor of stroke (hazard ratio 1.46, 95% confidence interval 0.74
to 2.88, p = 0.28). The risk of a cerebrovascular event among subjects with ASA
was nearly four times higher than that in those without ASA (hazard ratio 3.72,
95% confidence interval 0.88 to 15.71, p = 0.074).
CONCLUSIONS: These prospective population-based data suggest that, after
correction for age and comorbidity, PFO
is not an independent risk factor for future cerebrovascular events in
the general population. A larger study is required to test the putative stroke
risk associated with ASA.
Microvolt T-Wave Alternans and the Risk of Death or Sustained Ventricular
Arrhythmias in Patients With Left Ventricular Dysfunction
J Am Coll Cardiol 2006, 47:
456-463
Daniel M. Bloomfield, MD, FACC, J. Thomas
Bigger, MD, FACC, Richard C. Steinman, AB, Pearila B. Namerow, PhD, Michael K.
Parides, PhD, Anne B. Curtis, MD, FACC, Elizabeth S. Kaufman, MD, FACC, Jorge M.
Davidenko, MD, FACC, Timothy S. Shinn, MD, FACC and John M. Fontaine, MD, FACC
OBJECTIVES: This study
hypothesized that microvolt T-wave alternans (MTWA) improves selection of
patients for implantable cardioverter-defibrillator (ICD) prophylaxis,
especially by identifying patients who are not likely to benefit.
BACKGROUND: Many patients with left ventricular dysfunction are now eligible for
prophylactic ICDs, but most eligible patients do not benefit; MTWA testing has
been proposed to improve patient selection.
METHODS: Our study was conducted at 11 clinical centers in the U.S. Patients
were eligible if they had a left ventricular ejection fraction (LVEF) 0.40 and
lacked a history of sustained ventricular arrhythmias; patients were excluded
for atrial fibrillation, unstable coronary artery disease, or New York Heart
Association functional class IV heart failure. Participants underwent an MTWA
test and then were followed for about two years. The primary outcome was
all-cause mortality or non-fatal sustained ventricular arrhythmias.
RESULTS: Ischemic heart disease was present in 49%, mean LVEF was 0.25, and 66%
had an abnormal MTWA test. During 20 ± 6 months of follow-up, 51 end points (40
deaths and 11 non-fatal sustained ventricular arrhythmias) occurred. Comparing
patients with normal and abnormal MTWA tests, the hazard ratio for the primary
end point was 6.5 at two years (95% confidence interval 2.4 to 18.1, p < 0.001).
Survival of patients with normal MTWA tests was 97.5% at two years. The strong
association between MTWA and the primary end point was similar in all subgroups
tested.
CONCLUSIONS: Among patients with heart
disease and LVEF 0.40, MTWA can identify not only a high-risk group, but also a
low-risk group unlikely to benefit from ICD prophylaxis.
Preimplantation B-type natriuretic peptide concentration is an independent
predictor of future appropriate implantable defibrillator therapies
Heart 2006 92: 190-195
A Verma, F Kilicaslan, D O Martin, S
Minor, R Starling, N F Marrouche, S Almahammed, O M Wazni, S Duggal, R Zuzek, H
Yamaji, J Cummings, M K Chung, P J Tchou and A Natale
Objective: To assess
prospectively whether preimplantation B-type natriuretic peptide (BNP) and C
reactive protein (CRP) concentrations predict future appropriate therapies from
an implantable cardioverter-defibrillator (ICD).
Design and setting: Prospective cohort study conducted in a tertiary cardiac
care centre.
Methods: 345 consecutive patients undergoing first time ICD implantation were
prospectively studied. Serum BNP and CRP concentrations were obtained the day
before ICD implantation. Patients were followed up with device interrogation to
assess for appropriate shocks or antitachycardia pacing. Inappropriate therapies
were excluded. Mean (SD) follow up was 13 (5) months.
Results: Patients had ischaemic (71%), primary dilated (17%), and valvar or
other cardiomyopathies (12%). About half (52%) had ICDs implanted for primary
prevention. Sixty three (18%) received appropriate ICD therapies. Serum
creatinine, ß blocker, statin, and angiotensin converting enzyme inhibitor usage
did not differ between therapy and no therapy groups. By univariate comparison,
ejection fraction (p = 0.048), not taking amiodarone (p = 0.033), and BNP
concentration (p = 0.0003) were risk factors for ICD therapy. However, by Cox
regression multivariate analysis, only BNP above the 50th centile was a
significant predictor (hazard ratio 2.19, 95% confidence interval 1.07 to 4.71,
p = 0.040). Median BNP was 573 ng/l versus 243 ng/l in therapy and no therapy
patients, respectively (p = 0.0003). More patients with BNP above the 50th
centile (27% v 10%, p = 0.006) received ICD therapies.
Conclusions: A single preimplantation BNP concentration determination is
independently predictive of ICD therapies in patients with cardiomyopathies
undergoing first time ICD implantation. CRP was not independently predictive of
ICD therapies when compared with BNP.
Digoxin and reduction in mortality and hospitalization in heart failure: a
comprehensive post hoc analysis of the DIG trial
Eur Heart J 2006, 27: 178-186
Ali Ahmed, Michael W. Rich, Thomas E.
Love, Donald M. Lloyd-Jones, Inmaculada B. Aban, Wilson S. Colucci, Kirkwood F.
Adams and Mihai Gheorghiade
Aims To determine the effects
of digoxin on all-cause mortality and heart failure (HF) hospitalizations,
regardless of ejection fraction, accounting for serum digoxin concentration (SDC).
Methods and results This comprehensive post-hoc analysis of the randomized
controlled Digitalis Investigation Group trial (n=7788) focuses on 5548
patients: 1687 with SDC, drawn randomly at 1 month, and 3861 placebo patients,
alive at 1 month. Overall, 33% died and 31% had HF hospitalizations during a
40-month median follow-up. Compared with placebo, SDC 0.5–0.9 ng/mL was
associated with lower mortality [29 vs. 33% placebo; adjusted hazard ratio (AHR),
0.77; 95% confidence interval (CI), 0.67–0.89], all-cause hospitalizations (64
vs. 67% placebo; AHR, 0.85; 95% CI, 0.78–0.92) and HF hospitalizations (23 vs.
33% placebo; AHR, 0.62; 95% CI, 0.54–0.72). SDC 1.0 ng/mL was associated with
lower HF hospitalizations (29 vs. 33% placebo; AHR, 0.68; 95% CI, 0.59–0.79),
without any effect on mortality. SDC 0.5–0.9 reduced mortality in a wide
spectrum of HF patients and had no interaction with ejection fraction >45%
(P=0.834) or sex (P=0.917).
Conclusions Digoxin at SDC 0.5–0.9 ng/mL reduces mortality and hospitalizations
in all HF patients, including those with preserved systolic function.
At higher SDC, digoxin reduces HF hospitalization but has no effect on mortality or
all-cause hospitalizations.
Testosterone therapy in men with moderate severity heart failure: a double-blind
randomized placebo controlled trial
Eur Heart J 2006, 27: 57-64
Chris J. Malkin, Peter J. Pugh, John N.
West, Edwin J.R. van Beek, T. Hugh Jones and Kevin S. Channer
Aims Chronic heart failure is
associated with maladaptive and prolonged neurohormonal and pro-inflammatory
cytokine activation causing a metabolic shift favouring catabolism, vasodilator
incapacity, and loss of skeletal muscle bulk and function. In men, androgens are
important determinants of anabolic function and physical strength and also
possess anti-inflammatory and vasodilatory properties.
Methods and results We conducted a randomized, double-blind, placebo-controlled
parallel trial of testosterone replacement therapy (5 mg Androderm®) at
physiological doses in 76 men (mean±SD, age 64±9.9) with heart failure (ejection
fraction 32.5±11%) over a maximum follow-up period of 12 months. The primary
endpoint was functional capacity as assessed by the incremental shuttle walk
test (ISWT). At baseline, 18 (24%) had serum testosterone below the normal range
and bioavailable testosterone correlated with distance walked on the initial
ISWT (r=0.3, P=0.01). Exercise capacity significantly improved with testosterone
therapy compared with placebo over the full study period (mean change +25±15 m)
corresponding to a 15±11% improvement from baseline (P=0.006 ANOVA). Symptoms
improved by at least one functional class on testosterone in 13 (35%) vs. 3 (8%)
on placebo (P=0.01). No significant changes were found in handgrip strength,
skeletal muscle bulk by cross-sectional computed tomography, or in tumour
necrosis factor levels. Testosterone therapy was safe with no excess of adverse
events although the patch preparation was not well tolerated by the study
patients.
Conclusion Testosterone replacement therapy improves functional capacity and
symptoms in men with moderately severe heart failure.
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