Role of Implantable Cardioverter Defibrillator in Non-Ischemic Cardiomyopathy: a Systematic Review and Meta-Analysis of Prospective Randomized Clinical Trials.

INTRODUCTION: A mortality benefit in patients with implantable cardioverter defibrillator (ICD) in ischemic cardiomyopathy is well established. However, the benefit of ICD implantation in non-ischemic cardiomyopathy (NICM) on total mortality remains uncertain. We performed a systematic review and meta-analysis of randomized controlled trials (RCT) evaluating the role of primary prevention ICD in NICM patients. METHODS: We performed a systematic review on PubMed, The Cochrane Library, EMBASE, EBSCO, Web of Science, and CINAHL databases from the inception through February 2017 to identify RCT evaluating the role of ICD in NICM patients. Mantel-Haenszel risk ratio (RR) fixed effects model was used to summarize data across treatment arms. If heterogeneity (I (2)) ≥25, random effects model was used instead. RESULTS: We analyzed a total of 2573 patients from five RCTs comparing ICD with medical therapy in patients with NICM. The mean follow up for the trials was 48 ± 22 months. There was a significant reduction in (a) all-cause mortality (RR 0.84, 95% CI 0.71-0.99, p = 0.03) and (b) sudden cardiac death (RR 0.47, 95% CI 0.30-0.73, p \u3c 0.001) in ICD group versus medical therapy. CONCLUSION: Our analysis demonstrates that the use of ICD for primary prevention is associated with a reduction in all-cause mortality and SCD in patients with NICM