Abstract
BACKGROUND: Cardiac resynchronization therapy with defibrillation (CRT-D) improves outcomes in heart failure. The long-term impact of CRT-D on hospitalizations remains unknown. METHODS: We analyzed the MADIT-CRT (Multicenter Automatic Defibrillator Implantation Trial With Cardiac Resynchronization Therapy) trial post hoc to assess the effects of CRT-D versus implantable cardioverter-defibrillator (ICD) on cardiovascular, heart failure (HF), and noncardiovascular hospitalizations. Hospitalization rates, length of stay, and mortality were compared during extended follow-up. RESULTS: Patients receiving CRT-D had lower rates of hospitalization compared with ICD (37.9 events per 100 patient-years versus 44.3 events per 100 patient-years, P=0.033). Rates of cardiovascular hospitalizations (20.8 versus 28.3 events per 100 patient-years; P<0.001) and heart failure hospitalizations (6.8 versus 11.6 events per 100 patient-years; P<0.001) were lower with CRT-D. There was no difference in noncardiovascular hospitalizations in the CRT-D group compared with ICD (17 versus 16 events per 100 patient-years, P=0.368). The average length of stay for cardiovascular hospitalizations was shorter in the CRT-D group versus the ICD group (6.7±0.89 versus 7.7±0.68 days; P<0.001), as was the length of stay for heart failure hospitalizations (4.2±0.79 versus 4.8±0.58 days; P<0.001). No difference was observed in the length of stay for noncardiovascular hospitalizations (8.1 versus 7.0 days; P=0.082). Hospitalization of any type was associated with a markedly increased risk of death (hazard ratio, 8.97 [95% CI, 6.17-13.05]; P<0.0001). CONCLUSIONS: Among patients in MADIT-CRT, CRT-D was associated with lower rates and shorter durations of all cardiovascular hospitalizations, including heart failure hospitalizations compared with ICD alone. Hospitalization, regardless of cause, was strongly associated with increased mortality. REGISTRATION: https://clinicaltrials.gov/study/NCT00180271.