Implantable defibrillators significantly reduced the risk of death in patients with remote myocardial infarction (≥18 months) compared to conventional care (HR 0.55; 95% CI 0.39-0.78; P=0.001).
RCT (n=1,159)
3:2 ratio
Yes
Does an implantable defibrillator (ICD) reduce mortality in post-MI patients with ejection fractions <=30% depending on the elapsed time from MI?
The survival benefit of prophylactic ICDs in post-MI patients with LVEF <=30% is significantly greater for remote MI (>=18 months) compared to recent MI (<18 months).
Effect estimate: HR 0.55 (95% CI 0.39-0.78)
p-value: p=0.001
BACKGROUND: Prophylactic implantable defibrillators (ICDs) improve survival in patients with impaired ventricular function after myocardial infarction (MI), but it is uncertain whether mortality risk and survival benefit depend on the elapsed time from MI. METHODS AND RESULTS: The Multicenter Automatic Defibrillator Implantation Trial II examined the impact of ICDs on survival in post-MI patients with ejection fractions or =120 months). In conventional care patients, these rates increased as time from MI increased (7.8%, 8.4%, 11.6%, 14.0%; P=0.03). Mortality rates in ICD patients were consistently lower in each quartile and showed minimal increase over time (7.2%, 4.9%, 8.2%, 9.0%; P=0.19). Covariate-adjusted hazard ratios for risk of death associated with ICD therapy were 0.97 (95% CI, 0.51 to 1.81; P=0.92) for recent MI ( or =18 months). CONCLUSIONS: Mortality risk in patients with ejection fractions or =15 years after MI.
Wilber et al. (2004) conducted an RCT in Myocardial Infarction with impaired ventricular function (n=1,159). Implantable defibrillator (ICD) vs. Conventional care was evaluated on Risk of death (remote MI ≥18 months subgroup) (HR 0.55, 95% CI 0.39-0.78, p=0.001). Implantable defibrillators significantly reduced the risk of death in patients with remote myocardial infarction (≥18 months) compared to conventional care (HR 0.55; 95% CI 0.39-0.78; P=0.001).