Complications and Mortality Following CRT-D Versus ICD Implants in Older Medicare Beneficiaries With Heart Failure

Abstract

Objectives: This study sought to assess the comparative effectiveness of cardiac resynchronization therapy with defibrillator (CRT-D) over implantable cardioverter-defibrillator (ICD) alone in older Medicare patients with heart failure with reduced ejection fraction (HFrEF).

Background: Despite growing numbers of older patients with HFrEF, the benefits of cardiac resynchronization therapy (CRT) in this group are largely unknown.

Methods: A cohort of fee-for-service Medicare beneficiaries ≥65 years of age with HFrEF and enrolled in Medicare Part D who underwent CRT-D or ICD implantation from January 2008 to August 2015 was identified. Beneficiaries were divided by age (65-74, 75-84, and 85+ years), and outcomes were compared between the CRT-D and ICD groups after inverse probability weighting.

Results: Compared with the ICD group, the CRT-D group was older and more likely to be White, be female, and have left bundle branch block. After weighting, overall complications were high across age and device groups (14%-20%). The 1-year mortality was high across all groups. In the 2 oldest age strata, the hazard of death was lower in the CRT-D group (HR: 0.90; 95% CI: 0.86-0.95 and HR: 0.81; 95% CI: 0.72-0.90, respectively; P < 0.001); the hazard of heart failure hospitalization was lower for CRT-D vs ICD in the 85+ years age group (HR: 0.82; 95% CI: 0.74-0.92; P < 0.001).

Conclusions: In older Medicare beneficiaries undergoing ICD with or without CRT, complications and 1-year mortality were high. Compared with ICD alone, CRT-D was associated with a lower hazard of mortality in patients ≥74 years of age and lower hazard of HF hospitalization in those ≥85 years of age. These findings support the use of CRT in eligible older patients undergoing ICD implantation.

Keywords: cardiac resynchronization therapy; heart failure; implantable defibrillator; mortality.