Implantable cardioverter defibrillator in nonischemic cardiomyopathy: A systematic review and meta‐analysis

Abstract

The evidence to support implantable cardioverter defibrillator (ICD) in subjects with nonischemic cardiomyopathy (NICM) for primary prevention of sudden cardiac death (SCD) is not robust. This meta‐analysis intends to assess the impact of routine ICD implantation for primary prevention of mortality due to SCD in NICM based on all the published randomized clinical trials (RCTs). Six RCTs were selected using PubMed/Medline, EMBASE, and CENTRAL from inception to December 2016. Outcomes were calculated as random‐effects relative risk (RR) and risk difference (RD) with 95% confidence interval (CI). Patients were randomized to ICD arm and control arm (usual care, medical treatment, and anti‐arrhythmic drugs). ICD significantly reduced all‐cause mortality in NICM patients (RR, 0.74, 95% CI, 0.56‐0.97, P = .03, I2 = 40). Mortality benefit was achieved due to a significant reduction in sudden cardiac death (SCD) (RR, 0.47, 95% CI, 0.30‐0.73, P < .001, I2 = 0). There were no statistical differences between two groups with regard to risk of noncardiac mortality, non‐SCD, cardiac arrest, cardiac transplant, sustained ventricular tachycardia (VT), and VT requiring medical treatment. Our results support efficacy of ICDs at reducing all‐cause mortality due to a reduction in SCD.

Sinergy between drugs and devices in the fight against sudden cardiac death and heart failure

“…The evidence derived from these trials, indicating that ICDs are effective in improving overall survival at 2-5 years in appropriately selected patients with left ventricular dysfunction at high risk of SCD, was the basis for the recommendations for ICD implantation delivered by consensus guidelines. 3,10 The evidence of the benefit of ICD in non-ischaemic patients has always been less solid than in patients with ischaemic heart disease even if a meta-analysis including CAT, AMIOVERT, DEFINITE, and the non-ischaemic cohort of SCD-HeFT found a statistically significant benefit of ICD therapy on all-cause mortality, with a 26% relative risk reduction, 34 and this was the basis for the recommendations of international consensus guidelines. 3,10 The most recent trial is the DANISH ICD study, 35 a trial specifically targeted to evaluate the impact of ICD implant in the setting of systolic dysfunction due to non-ischaemic cardiomyopathy.…”

Delayed Improvement of Left Ventricular Function in Newly Diagnosed Heart Failure Depends on Etiology—A PROLONG-II Substudy

“…While the prognosis of patients with HFrEF is improving, ICD complication rates remain non-negligible [6,7,9,28]. The net benefit of a primary preventive ICD has been questioned by recent trials, especially in patients with non-ischemic cardiomyopathy [29][30][31][32]. As a consequence, guideline recommendations by the ESC were downgraded for patients with non-ischemic cardiomyopathy [5].…”

A Systematic Review and Single-center Experience of Azygos Vein Defibrillator Lead Insertion

“…We also analyzed the clinical characteristics and outcomes of patients from the study group compared to the conventional ICD candidates. In the most recent meta-analysis of 6 randomized controlled trials by Khan et al, 10 who studied the efficacy of ICDs in NICM, the medium age of conventional ICD recipients was 60 years and men composed 73% of the cohort. In our pooled cohort, the mean age was 47 years, with 92% being men.…”