Do implantable cardioverter defibrillators improve survival in patients with chronic kidney disease at high risk of sudden cardiac death? A meta-analysis of observational studies

Abstract

Prospective randomized clinical trials show that implantable cardioverter defibrillators (ICDs) can reduce the risk of total mortality in select populations. However, data regarding patients with chronic kidney disease (CKD) are inconclusive. The aim of this study was to evaluate if ICDs affect total mortality in CKD patients at high risk of sudden cardiac death. Two separate meta-analyses were performed to (i) assess the effect of ICD on all-cause mortality in CKD patients at high risk of sudden cardiac death and (ii) assess the effect of CKD on all-cause mortality in patients who already had an ICD for primary or secondary prevention purposes. Medline and EMBASE were searched from 1966 to 2013. A manual search by cross-referencing was performed. Five observational studies with 17 460 CKD patients considered at high risk of sudden cardiac death were included to evaluate the effect of ICDs on patients with severe CKD. Patients with ICD implants had a reduction in all-cause mortality (adjusted hazard ratio (HR) = 0.65, 95% confidence interval (CI) = 0.47-0.91, P < 0.05) compared with a matched control group. Based on 15 observational studies with 5233 patients as part of our second comparison that evaluated the effect of CKD on patients who received an ICD, CKD was associated with higher mortality risk (HR = 2.86, 95% CI = 1.91-4.27, P < 0.05) despite an ICD. The meta-analysis indicates that for patients undergoing ICD implant, CKD is associated with greater risk of dying. However, ICD placement reduces mortality in CKD patients at high risk of sudden cardiac death.