Sex differences in cardiac remodelling in ischaemic cardiomyopathy and functional mitral regurgitation: impact on prognosis

Aims Sex differences in prognosis of functional mitral regurgitation (FMR) associated with ischaemic cardiomyopathy (ICM) demonstrate the need to identify sex differences in cardiac remodelling. This study aimed to characterize sex differences in cardiac remodelling associated with FMR in the setting of ICM, sex interactions with cardiac remodelling and FMR severity, and predictors of all-cause mortality or heart transplantation using cardiac magnetic resonance (CMR) imaging. Methods and results Consecutive patients with ICM referred to CMR between 2002 and 2017 were reviewed. Eligible 790 patients [mean age: 62.0 (standard deviation = 11.2] years and 24.7% females] were evaluated over a median follow-up of 5.8 years. There were 773 subjects with complete data for survival analysis, with 449 primary events. Coronary artery disease risk factors, medications, and previous coronary revascularization were similar in females and males (all P > 0.05). Indexed left ventricular and right ventricular (LV and RV) volumes were larger in males (P < or =0.005 for all comparisons) with similar slope of increasing LV and RV volumes in the setting of increasing FMR (all P > 0.05, for interactions). However, indexed left atrial volume was similar in males and females (P = 0.696), after adjusting for FMR severity. After adjusting for medical risk factors and post-CMR procedural interventions, females demonstrated increased risk of primary clinical composite point with enlarging LV volumes [hazard ratio: 1.04 (95% confidence interval: 1.01–1.06), P = 0.034]. Conclusion Because females with increasing LV size and FMR severity demonstrated significantly increased risk of adverse outcomes, our findings suggest the importance of deriving sex-specific CMR selection criteria for therapeutic management of FMR in the setting of ICM.