Mortality benefits from implantable cardioverter-defibrillator therapy are not restricted to patients with remote myocardial infarction: an analysis from the Sudden Cardiac Death in Heart Failure Trial (SCD-HeFT).
BACKGROUND
The implantable cardioverter-defibrillator (ICD) is an effective therapy for preventing sudden cardiac death (SCD) in patients with prior myocardial infarction (MI) and reduced left ventricular function; however, the optimal timing of ICD implantation after MI remains unknown.


OBJECTIVE
The purpose of this study was to determine whether the benefit of single-lead conservatively programmed ICD therapy varies as a function of time from MI to ICD implantation.


METHODS
We compared time to all-cause death and SCD between the ICD and placebo arms in the Sudden Cardiac Death in Heart Failure Trial. Rates of appropriate shocks in the ICD arm were also assessed as a function of time after MI.


RESULTS
Among the 712 patients with a history of MI, 274 died (38.5%), and 68 of these deaths were SCD (24.8%). Appropriate shocks were more common with increasing time after MI (adjusted hazard ratio [HR] per year after MI 1.04 [1.00-1.08]). Despite these differences, there was no evidence of differential mortality benefit with ICD implantation as a function of time after MI: continuous variable adjusted HR 1.00 [0.98,1.03] and shortest versus longest tertile adjusted HR 0.95 [0.66-1.34]. Sensitivity analyses also failed to show differential mortality benefit by quartile or with the use of an 18-month cutoff: <18 versus ≥ 18 months adjusted HR 1.08 [0.77, 1.51].


CONCLUSIONS
There is no evidence that ICD benefit varied with time from MI to implantation/randomization in this primary prevention population. Single-lead ICD benefit is not restricted to patients with a remote MI (>18 months).
Division of Cardiology, Duke University Medical Center, Durham, North Carolina 27710, USA. jonathan.piccini@duke.edu
Jonathan P
JP
Piccini
Sana M
SM
Al-Khatib
Anne S
AS
Hellkamp
Kevin J
KJ
Anstrom
Jeanne E
JE
Poole
Daniel B
DB
Mark
Kerry L
KL
Lee
Gust H
GH
Bardy
D000368:Aged; D016757:Death, Sudden, Cardiac / Q000517:prevention & control*; D017147:Defibrillators, Implantable; D005260:Female; D006333:Heart Failure / Q000401:mortality*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000401:mortality*; D016016:Proportional Hazards Models; D013997:Time Factors