Gender Differences in Cardiac Resynchronization Therapy Device Choice and Outcome in Patients ≥75 Years of Age with Heart Failure.

Cardiac resynchronization therapy (CRT) is an established therapy for heart failure and can be delivered through a CRT pacemaker (CRT-P) or a CRT defibrillator (CRT-D). CRT-P devices are smaller and less expensive, have better battery longevity, and have been subject to fewer recalls and advisories but cannot deliver high-energy shocks to terminate potentially lethal ventricular arrhythmias. As published guidelines do not distinguish between CRT-P and CRT-D indications, we examined the practice of prescribing these devices in older women and men with heart failure. A total of 512 CRT recipients (age ≥75 years, 26% women, 21% CRT-P) were included in this analysis. Baseline characteristics were collected on all patients, and overall survival was compared by gender and type of CRT device implanted. Women were more likely to receive CRT-Ps than men (26% vs 19%). Men with CRT-Ps were significantly older than women with CRT-Ps and both men and women with CRT-Ds (p = 0.04). In addition, women had lower all-cause mortality compared with men (hazard ratio [HR] 0.75, confidence interval [CI] 0.58 to 0.99, p = 0.04), mainly among CRT-P recipients (HR 0.48, CI 0.26 to 0.8, p = 0.02), but this association was attenuated after adjusting for differences in patient characteristics (HR 0.56, CI 0.26 to 1.18, p = 0.13). In conclusion, women are more likely to receive CRT-Ps than men. Whether this difference is driven by patient preference or physician biases remains unclear. Women with CRT, particularly CRT-Ps, have a better overall survival than men. These differences, which may be driven by unbalanced baseline characteristics of patients or by differences in gender response to CRT, deserve further investigation.