January 20, 2005
Seattle, WA – In
patients with NYHA class II or III congestive heart failure
implantable cardioverter-defibrillator therapy reduces
mortality, while amiodarone has no favorable effect. A
randomized, double-blind trial of amiodarone and ICD therapy was
performed and published by Gust H. Bardy, et. al, from the
Seattle Institute for Cardiac Research in the January 20, 2005
issue of the New England Journal of Medicine. This study
compared the effects of amiodarone versus ICD therapy on
mortality in patients with congestive heart failure and found
that only ICD therapy conferred a significant benefit when
compared with placebo.
Both treatment with amiodarone and ICD therapy have been
proposed to improve the prognosis in patients with congestive
heart failure, but prior to this study neither had been directly
compared in a randomized, double blind, placebo controlled
The study randomization period began in September 1997 and ended
in July of 2001, during which 2,521 patients were randomized to
receive either placebo, amiodarone, or a single chamber ICD.
Patients had to have NYHA class II or III heart failure with a
left ventricle ejection fraction of no greater than 35 percent.
Of these patients, 847 were assigned to placebo, 845 to
amiodarone, and 829 to ICD therapy. The primary endpoint of the
trial was death from any cause. Placebo and amiodarone were
administered in a double blind fashion. The ICDs were uniformly
programmed to have a detection rate of 187 beats per minute or
Out of the 829 patients in the ICD group, 259 (31 percent) were
known to have received shocks from their device for any cause.
During the five years of follow-up, the average annual rate of
ICD shocks was 7.5 percent.
A total of 666 patients died: 244 (29 percent) in the placebo
group, 240 (28 percent) in the amiodarone group, and 182 (22
percent) in the ICD group. As compared with placebo, amiodarone
therapy was associated with a similar risk of death (hazard
ratio, 1.06; 97.5 percent confidence interval 0.86 to 1.30;
P=0.53) and ICD therapy was associated with a decreased risk of
death (hazard ratio, 0.77; 97.5 percent confidence interval 0.62
to 0.96; P=0.007).
Interestingly, patients who had NYHA class II heart failure
showed a greater benefit from ICD therapy, while patients with
NYHA class III heart failure did not show a benefit
significantly greater than placebo with the ICD therapy.
These results indicated that for this patient population, ICD
therapy is effective in decreasing mortality, while amiodarone
does not appear to offer any benefit when compared with placebo
Co-authors: Kerry L. Lee, Ph.D., Daniel B. Mark, M.D., Jeanne E.
Poole, M.D., Douglas L. Packer, M.D., Robin Boineau, M.D.,
Michael Domanski, M.D., Charles Troutman, R.N., Jill Anderson,
B.S.E.E., Steven E. McNulty, M.S., Nancy Clapp-Channing, R.N.,
M.P.H., Linda D. Davidson-Ray, M.A., Elizabeth S. Fraulo, R.N.,
Daniel P. Fishbein, M.D., Richard M. Luceri, M.D.,
and John H. Ip, M.D.