Primary Prevention Implantable Cardioverter Defibrillator (ICD) Therapy in Women-Data From a Multicenter French Registry

Abstract

Background: There are limited data describing sex specificities regarding implantable cardioverter defibrillators (ICDs) in the real-world European setting.

Methods and results: Using a large multicenter cohort of consecutive patients referred for ICD implantation for primary prevention (2002-2012), in ischemic and nonischemic cardiomyopathy, we examined the sex differences in subjects' characteristics and outcomes. Of 5539 patients, only 837 (15.1%) were women and 53.8% received cardiac resynchronization therapy. Compared to men, women presented a significantly higher proportion of nonischemic cardiomyopathy (60.2% versus 36.2%, P<0.001), wider QRS complex width (QRS >120 ms: 74.6% versus 68.5%, P=0.003), higher New York Heart Association functional class (≥III in 54.2%♀ versus 47.8%♂, P=0.014), and lower prevalence of atrial fibrillation (18.7% versus 24.9%, P<0.001). During a 16 786 patient-years follow-up, overall, fewer appropriate therapies were observed in women (hazard ratio=0.59, 95% CI 0.45-0.76; P<0.001). By contrast, no sex-specific interaction was observed for inappropriate shocks (odds ratio ♀=0.84, 95% CI 0.50-1.39, P=0.492), early complications (odds ratio=1.00, 95% CI 0.75-1.32, P=0.992), and all-cause mortality (hazard ratio=0.87 95% CI 0.66-1.15, P=0.324). Analysis of sex-by- cardiac resynchronization therapy interaction shows than female cardiac resynchronization therapy recipients experienced fewer appropriate therapies than men (hazard ratio=0.62, 95% CI 0.50-0.77; P<0.001) and lower mortality (hazard ratio=0.68, 95% CI 0.47-0.97; P=0.034).

Conclusions: In our real-life registry, women account for the minority of ICD recipients and presented with a different clinical profile. Whereas female cardiac resynchronization therapy recipients had a lower incidence of appropriate ICD therapies and all-cause death than their male counterparts, the observed rates of inappropriate shocks and early complications in all ICD recipients were comparable.

Clinical trial registration: URL: https://www.clinicaltrials.gov/. Unique identifier: NCT01992458.

Keywords: death, sudden; heart failure; mortality; shock.