Estimated Glomerular Filtration Rate and Implantable Cardioverter‐Defibrillator in Nonischemic Systolic Heart Failure: Extended Follow‐Up of DANISH

Abstract

Background Patients with heart failure and chronic kidney disease (CKD) may have an increased risk of death from causes competing with arrhythmic death, which could have implications for the efficacy of implantable cardioverter‐defibrillators (ICDs). We examined the long‐term effects of primary prophylactic ICD implantation, compared with usual care, according to baseline CKD status in an extended follow‐up study of DANISH (Danish Study to Assess the Efficacy of ICDs in Patients With Nonischemic Systolic Heart Failure on Mortality). Methods and Results In the DANISH trial, 1116 patients with nonischemic heart failure with reduced ejection fraction were randomized to receive an ICD (N=556) or usual care (N=550). Outcomes were analyzed according to CKD status (estimated glomerular filtration rate ≥/<60 mL/min per 1.73 m 2 ) at baseline. In total, 1113 patients had an available estimated glomerular filtration rate measurement at baseline (median estimated glomerular filtration rate 73 mL/min per 1.73 m 2 ), and 316 (28%) had CKD. During a median follow‐up of 9.5 years, ICD implantation, compared with usual care, did not reduce the rate of all‐cause mortality (no CKD, HR, 0.82 [95% CI, 0.64–1.04]; CKD, HR, 1.02 [95% CI, 0.75–1.38]; P interaction =0.31) or cardiovascular death (no CKD, HR, 0.77 [95% CI, 0.58–1.03]; CKD, HR, 1.05 [95% CI, 0.73–1.51]; P interaction =0.20), irrespective of baseline CKD status. Similarly, baseline CKD status did not modify the beneficial effects of ICD implantation on sudden cardiovascular death (no CKD, HR, 0.57 [95% CI, 0.32–1.00]; CKD, HR, 0.65 [95% CI, 0.34–1.24]; P interaction =0.70). Conclusions ICD implantation, compared with usual care, did not reduce the overall mortality rate, but it did reduce the rate of sudden cardiovascular death, regardless of baseline kidney function in patients with nonischemic heart failure with reduced ejection fraction. Registration URL: https://www.clinicaltrials.gov ; Unique identifier: NCT00542945.