Download The Clinical Evidence: An Overview of ICD Studies in Primary

The Clinical Evidence: An Overview of ICD Studies in Primary Prevention Patients
The role of implantable cardioverter defibrillators (ICDs) in secondary prevention (patients with a history of sudden cardiac arrest (SCA) or sustained ventricular tachycardia (VT), is well established and the medical community is now studying the use of ICDs in primary
prevention patients, those people who have not had a SCA or sustained VT. Three major clinical trials investigating ICD therapy in primary prevention patients (MADIT, MUSTT and MADIT II) have shown significant reductions in overall mortality (31-55%) over
antiarrhythmics or conventional medical therapy. Results of a fifth primary prevention study, the landmark Sudden Cardiac Death in Heart Failure Trial (SCD-HeFT), sponsored by the National Heart Lung and Blood Institute of the National Institutes of Health, is expected
to be announced in the first quarter of 2004.
Name
Publication Details
Study Objective
Study Design
Patient Criteria
Primary
Endpoint
Results
Conclusions
Multicenter Automatic
Defibrillator Implantation
Trial (MADIT)
Moss AJ. N Engl J
Med. 1996
To evaluate if prophylactic therapy
with an ICD, as compared with
conventional medical therapy, would
improve survival in patients with a
previous heart attack and left
ventricular dysfunction
196 patients were enrolled
• 95 were randomly assigned to
receive an ICD
• 101 were assigned to receive
conventional medical therapy
Patients had a prior heart attack; a left
ventricular ejection fraction (LVEF) of
less than 35%; a documented episode
of asymptomatic unsustained
ventricular tachycardia (VT); and
inducible, nonsuppressible ventricular
tachyarrhythmia
Death from
any cause
54% reduction in mortality with ICD
therapy
In post-heart attack patients at a
high risk for VT, prophylactic
therapy with an implanted
defibrillator reduced overall
mortality by 54% and arrhythmic
mortality by 75% compared with
conventional medical therapy
Multicenter Unsustained
Tachycardia Trial
(MUSTT)
Buxton AE. N Engl J
Med. 1999
To evaluate the efficacy of
antiarrhythmic therapy guided by
electrophysiologic (EP) testing in
reducing the risk of sudden death
and cardiac arrest among patients
with coronary artery disease (CAD),
left ventricular dysfunction, and
asymptomatic, unsustained VT
704 patients were enrolled and
randomized
• 351 were assigned to receive
EP guided therapy
• 353 were assigned to receive
no antiarrhythmic therapy
Patients had coronary artery disease, a
LVEF of 40% or less, asymptomatic,
unsustained VT; inducible VT via EP
testing
Arrhythmic
death or
cardiac arrest
55-60% reduction in mortality with ICD
therapy
Electrophysiologically guided
antiarrhythmic therapy with
ICDs, but not with
antiarrhythmic drugs, reduces
the risk of sudden death in highrisk patients with coronary
disease
Multicenter Automatic
Defibrillator Implantation
Trial-II
(MADIT II)
Moss AJ. N Engl J
Med. 2002
To evaluate the effect of ICD therapy
on survival in patients with reduced
left ventricular function after a heart
attack
1232 patients were enrolled
• 742 received an ICD
• 490 received conventional
medical therapy
Patients had a heart attack and an
ejection fraction (EF) of less than or
equal to 30%
Death from
any cause
31% reduction in mortality with ICD
therapy
In patients with a prior heart
attack and advanced left
ventricular dysfunction,
prophalytic implantation of an
ICD improves survival and
should be considered as a
recommended therapy
DEFibrillators In NonIschemic
Cardiomyopathy
Treatment Evaluation
(DEFINITE)
TBD Results presented at
the American Heart
Association Scientific
Sessions, by Kadish
A, November 11,
2003
To evaluate if ICD therapy can
improve survival in non-ischemic
(dilated) cardiomyopathy heart failure
patients
458 patients were enrolled and
randomized into two treatment
groups
• 229 received standard heart
failure drug therapy
• 229 received standard drug
therapy plus an ICD
Patients with non-ischemic dilated
cardiomyopathy, LVEF 35% or less,
and spontaneous premature ventricular
complexes or non-sustained VT
Death from
any cause
Unpublished
TBD
Sudden Cardiac Death
In Heart Failure Trial
(SCD-HEFT)
TBD
To evaluate if amiodarone and/or
ICD therapy will improve survival
compared to placebo in patients with
coronary heart failure (CHF) without
a history of sustained VT who have
not had a previous life-threatening
arrhythmic episode
2,521 patients were enrolled, and
randomized equally
• ICD therapy
• Amiodarone (drug therapy)
• Control group
Patients must have Class II or III CHF,
a LVEF of 35% or less, have ischemic
or non-ischemic dilated cardiomyopathy
(DCM) and have had CHF for at least
three months
Death from
any cause
Follow-up period completed October
31, 2003
TBD
Study results available March 8, 2004
at ACC late-breaking trial session