Gender differences in post-infarction hypertrophy in end-stage failing hearts.

OBJECTIVES We explored whether there are gender differences in cardiac remodeling and whether etiology influences organ and cellular remodeling in advanced heart failure (HF). BACKGROUND Several studies have shown a survival benefit for women compared to men with symptomatic HF. This observation may be related to gender differences in cardiac remodeling. METHODS We studied hearts from 100 patients (72 men and 28 women) receiving cardiac transplantation at our institution. Cardiac morphology was assessed with echocardiography and direct measurement of cardiac mass. Cardiac myocyte volume, length, width, cross-sectional area, and contraction were measured using previously validated techniques. RESULTS Among 50 patients with idiopathic cardiomyopathy (CM), we observed no gender-based differences in cardiac or cellular remodeling. In contrast, among 50 patients with ischemic cardiomyopathy (ICM), the heart weight index was significantly greater in men, and there was a strong trend toward an increased left ventricular (LV) mass index as well. These gender differences in cardiac and LV mass were paralleled by marked gender differences in myocyte volume, such that average myocyte volume was 36% greater in men than in women, in association with a 14% increase in resting cell length. CONCLUSIONS Our studies demonstrate a multilevel gender difference in post-infarction remodeling, with women exhibiting reduced hypertrophy. Our studies further demonstrate that gender differences in cardiac remodeling in ICM are largely related to fundamental differences in cellular remodeling rather than simply differences in infarct size or expansion. Distinctions observed between ischemic and idiopathic CM suggest that gender may influence local myocardial responses to injury.