Sex-Related Differences in Patients with Mitral Regurgitation Undergoing Mitral Valve Surgery: A Propensity...

Background/Objectives: Sex-related differences in the presentation and outcomes of patients with mitral regurgitation (MR) undergoing mitral valve (MV) surgery remain unclear. We aimed to identify these differences to inform personalized management. Methods: A total of 143 consecutive patients undergoing surgery for MR between 2017 and 2018 were stratified by sex and assessed for differences in characteristics. We performed 1:1 propensity score matching (PSM) by sex, with baseline characteristics as covariates, yielding 38 comparable pairs which were analyzed for differences in all-cause mortality and post-operative length of stay (LOS). Results: Females (n = 67) were more symptomatic (NYHA Class ≥ 3: 73% vs. 45%, p < 0.001), had higher logistic EuroSCORE (5.5 vs. 3.9, p = 0.006), had more urgent operations (25% vs. 11%, p = 0.020), MV replacements (28% vs. 11%, p = 0.007), and secondary MR (43% vs. 16%, p < 0.001). Females had significantly smaller end-diastolic and end-systolic left ventricular (LV) diameters, though indexed diameters showed no significant differences. After PSM, females had significantly longer LOS (7 days vs. 9 days, p = 0.033) and no differences in long-term mortality (hazard ratio [HR]: 1.25, 95% confidence interval [CI]: 0.34-4.76, p = 0.7, median follow-up: 6.67 years). An indexed LV end-systolic diameter (LVESDi) > 19 mm/m² yielded greater specificity (46.0% vs. 26.7%) and comparable sensitivity (69.4% vs. 69.2%) to LVESD > 40 mm. In subgroup analyses, female patients undergoing concomitant tricuspid intervention (HR: 6.80 [1.63-37.92], p < 0.01) or urgent operation (HR: 4.85 [1.08-21.06], p = 0.04) had worse prognoses than males. Conclusions: Females undergoing MV surgery for MR had more symptoms, higher surgical risk, and longer LOS, but similar mortality compared to males. However, concomitant tricuspid intervention and urgent operations were associated with higher mortality. Our results add to the growing body of evidence that current non-indexed LV diameter thresholds may not adequately account for sex differences.