Sex Differences in Left Ventricular Size and Function before and after Mitral Valve Repair

BACKGROUND: Among healthy subjects, women have smaller cardiac size than men even after indexing for body surface area (BSA), as well as higher left ventricular ejection fraction (LVEF) and left ventricular (LV) global longitudinal strain (GLS). Despite this, little is known about sex differences in LV remodeling in patients with mitral valve prolapse (MVP) undergoing mitral valve repair (MVr). The aim of this study was to assess pre- and post-MVr sex differences in LV size and function in patients with MVP. METHODS: Patients with MVP who underwent surgery between 2007 and 2024 at two heart valve centers were included. Those with previous cardiac surgery, coronary artery disease, other concomitant procedures than tricuspid valve repair, nonsinus rhythm at baseline, and with significant postsurgical mitral regurgitation (grade ≥ 2) were excluded. LV size was evaluated before and after surgery using both end-systolic diameter (ESD) and end-systolic volume (ESV), while LV function was assessed using LVEF and GLS. Thresholds for normal sex-specific LV size and function were based on current recommendations. The primary outcome was postoperative LV damage, defined as the presence of increased LV ESV index, impaired LVEF, or impaired LV GLS. The ability of preoperative measures of LV size to discriminate outcomes was assessed using receiver operating characteristic curve analyses. RESULTS: in women, with an area under the curve of 0.68. CONCLUSIONS: In patients with MVP undergoing MVr, women have higher BSA-adjusted LV size by ESD, whereas ESV remains larger in men. Only men demonstrate a significant reduction in LV ESV after MVr, whereas women are more prone to postoperative LV dilatation and dysfunction. The present findings suggest that women are undergoing surgery at a later stage of disease and support the need for sex-specific assessment of preoperative LV size when referring patients to mitral valve surgery.