Cardiac resynchronization therapy: do women benefit more than men?

Women are underrepresented in cardiac resynchronization therapy (CRT) trials. Whether there is a gender difference in the benefit derived from CRT has not been well studied.

This study included 728 consecutive CRT recipients at our institution who met guidelines for placement of a CRT device. Clinical characteristics and echocardiographic parameters were collected at baseline and after CRT; Kaplan-Meier survival analysis was performed using a national death and location database. The effects and outcome of CRT were compared between women and men.

Of 728 patients, 166 were female (22.8%). Female patients were younger than male patients (66.0 ± 11.9 years vs 69.4 ± 10.9 years; P < 0.001) and more often had nonischemic cardiomyopathy (68% vs 36%; P < 0.001). Both female and male patients had significantly improved clinical and echocardiographic parameters after CRT. The magnitude of improvement was similar in women and men, except that improvement in New York Heart Association (NYHA) class was greater in women than in men (-0.79 ± 0.78 vs -0.56 ± 0.85; P = 0.009). Although women were at lower risk of death than men after CRT (hazard ratio, 0.51; 95% confidence interval, 0.35-0.75; P < 0.001, unadjusted), multivariate analysis indicated gender was not, but age at CRT placement, cardiomyopathy cause, NYHA class, and lead location were independent predictors of survival.

Female CRT recipients seem to achieve greater survival benefit than male recipients. However, this benefit is majorly driven by nonischemic cardiomyopathy and other clinical factors.