Renal dialysis as a risk factor for appropriate therapies and mortality in implantable cardioverter-defibrillator recipients

Background: Patients with end-stage renal disease are at increased risk for sudden cardiac death, although the utility of implantable cardioverter-defibrillators (ICDs) in these patients is unknown. Objectives: The purpose of this study was to evaluate whether end-stage renal disease is an independent risk factor for appropriate ICD therapy for ventricular tachycardia (VT) or ventricular fibrillation (VF) and to compare the long-term survival of ICD recipients with and without end-stage renal disease. Methods: A retrospective cohort study was performed on ICD recipients at a single center. The primary endpoint was first appropriate ICD therapy for VT/VF. The secondary endpoint was survival. Results: The study included 585 patients, 19 (3.2%) of whom had end-stage renal disease prior to device implantation. Average follow-up time was 2.2 ± 2.4 years, during which time 156 patients (26.7%) received appropriate ICD therapy. End-stage renal disease was strongly associated with appropriate ICD therapy (hazard ratio 2.30, 95% confidence interval 1.17-4.54) and remained a significant predictor following adjustment for implant indication, ejection fraction, diabetes, hypertension, and beta-blocker use. Survival was significantly shorter in the end-stage renal disease patients, with a median survival time of 3.2 ± 0.6 (SEM) years in the dialysis cohort and 7.4 ± 0.5 (SEM) years in those without end-stage renal disease (log rank P = .009). The majority of deaths in the end-stage renal disease cohort were due to non-device-related infection. Conclusion: In this cohort, end-stage renal disease was the single greatest predictor of ICD therapies for VT/VF. The survival rate was significantly shorter than that of ICD recipients without end-stage renal disease, suggesting that comorbidities in end-stage renal disease patients meeting current implant indications may reduce the survival benefit of ICD placement in this population.