Abstract 13355: Women have Better Survival than Men with Cardiac Resynchronization Therapy in Left Bundle Branch Block: an Observational Comparative Effectiveness Study from the National Cardiovascular Data Registry
Background: Women and patients without left bundle branch block (LBBB) were underrepresented in cardiac resynchronization therapy defibrillator (CRT-D) trials. Therefore, trial results primarily reflect outcomes in men with LBBB (~75% of enrollees).
Objective: To compare risk of death between patients treated with CRT-D and those receiving implantable defibrillators (ICD) in subgroups by sex, QRS morphology and duration in the National Cardiovascular Data Registry ICD Registry between 2006-2010.
Methods: We used inverse probability treatment weighting (IPTW) to control for differences in case-mix between CRT-D and ICD. Propensity scores were calculated and weighted using 25 variables including age, LVEF, NYHA class, ischemic cardiomyopathy, atrial fibrillation/flutter, renal failure/dialysis, diabetes and hypertension. Subjects were categorized according to QRS morphology (LBBB vs. non-LBBB) and duration in 10 ms increments. We assessed adjusted survival curves and hazard ratios (HR) in 75,079 patients with up to 5 years of follow-up in the social security administration death master file.
Results: In patients with LBBB, women receiving CRT-D had a 26% lower risk of death than those receiving ICD (HR=0.74 [95% CI 0.68-0.81]); the risk difference was 16% in men (HR=0.84 [0.79-0.89]), p=0.025 for interaction. Among those with non-LBBB, women had a 12% lower risk (HR=0.88 [0.79-0.97]) with CRT-D while men had a 5% lower risk (HR=0.95 [0.91-0.998]), p=0.17 for interaction (Figure). CRT-D was associated with a better survival in both sexes with LBBB and QRS ≥130 ms while there was no clear relation between QRS duration and survival in patients with non-LBBB.
Conclusions: In a large real-world population comparing CRT-D with ICD therapy, CRT-D was associated with a lower mortality risk among both women and men with LBBB, though the difference was less pronounced among men. Among LBBB morphology only, both sexes had better survival with longer QRS duration.
Author Disclosures: R. Zusterzeel: None. E.S. Spatz: None. J.P. Curtis: Other Research Support; Modest; ACC NCDR. Other; Modest; Equity interest Medtronic. W.E. Sanders: None. K.A. Selzman: None. I.L. Piña: Honoraria; Modest; Novartis, GE Healthcare. H. Bao: None. A. Ponirakis: None. P.D. Varosy: None. F.A. Masoudi: Other; Modest; Senior Medical Officer NCDR. D.A. Caños: None. D.G. Strauss: None.
- © 2014 by American Heart Association, Inc.