Effectiveness of Implantable Cardioverter-Defibrillators for the Primary Prevention of Sudden Cardiac Death in Women With Advanced Heart Failure A Meta-analysis of Randomized Controlled Trials

Background: Numerous clinical trials have established a role for implantable cardioverter-defibrillators in the prevention of sudden cardiac death in patients with heart failure. However, questions remain that regard the clinical benefit of these therapies in different patient subgroups. Specifically, the role of implantable cardioverter-defibrillators in women with heart failure for the primary prevention of sudden cardiac death has not been well established. Our objective is to determine whether implantable cardioverter-defibrillators reduce mortality in women with advanced heart failure. Methods: We searched MEDLINE (1950-2008), EMBASE (1988-2008, week 24), the Cochrane Controlled Trials Register (third quarter, 2008), the National Institute of Health ClinicalTrials.gov database, the Food and Drug Administration Web site, and various reports presented at scientific meetings (1994-2007). Eligible studies were randomized controlled trials of implantable cardioverter/defibrillators for the primary prevention of sudden cardiac death in patients with heart failure that reported all-cause mortality as an outcome for the female population. Of the 2619 reports identified, 5 trials that enroll 934 women were included in the meta-analysis. Results: Pooled data from the 5 trials revealed no statistically significant decrease in all-cause mortality in women with heart failure who receive implantable cardioverter-defibrillators (hazard ratio, 1.01; 95% confidence interval, 0.76-1.33). Conclusions: Implantable cardioverter-defibrillator therapy for the primary prevention of sudden cardiac death in women does not reduce all-cause mortality. Further studies are needed to investigate the reasons for this observation and to define the population of women who may benefit most from implantable cardioverter-defibrillator therapy.