Sex differences in left ventricular remodeling and function in patients with mitral valve prolapse undergoing mitral valve repair

Abstract Background In healthy subjects, women have smaller cardiac chambers than men even after indexation by body surface area (BSA), as well as higher left ventricular (LV) ejection fraction (EF) and global longitudinal strain (GLS). The current guidelines for management of severe degenerative mitral regurgitation (MR) do not take these differences into account when referring patients to surgery. Purpose To assess the sex-specific pre- and postoperative LV remodeling and function in patients with mitral valve prolapse (MVP). Methods Patients with MVP undergoing mitral valve repair between 2007-2024 at two Heart Valve Centers were included. We excluded patients with previous cardiac surgery, coronary artery disease, other concomitant procedures than tricuspid valve repair, non-sinus rhythm at baseline and those with significant post-surgical MR (≥2+). Cutoffs for defining normal LV chamber size and function were based on current guidelines. Results 174 patients (36 % women) were assessed before and at a median of 14 11-23 months after surgery. At baseline, women were older, had more often dyspnoea and palpitations (all p 0.05), and smaller non-indexed LV diameters and volumes compared to men (Figure 1). Using sex-specific cutoffs and indexation by BSA, women had more often dilated LVs by both LV end-systolic diameter and volume, but LV dilatation by volume was a more sensitive marker in both sexes (Figure 2). At follow-up, women were more likely to have persistent LV dilatation (Figure 2). In logistic regression analysis, women had 7.2 (95 % CI 2.8-18.2) times higher probability of having persistently enlarged LV end-systolic volume indexed by BSA after surgery, after adjustment for age, MVP phenotype, LV EF, systolic pulmonary artery pressure and baseline LV end-systolic volume indexed by BSA. LV EF was similar between sexes at baseline, while LV GLS was higher in women than in men (Figure 2). Whereas LV dysfunction was a rare finding before surgery, low LV EF and GLS were significantly more frequent in women after surgery (Figure 2). Women also had 3.2 (95 % CI 1.4-7.1) times higher probability of having low LV GLS after surgery, after adjustment for age, baseline LV GLS, LV end-systolic diameter indexed by BSA, left atrial reservoir strain and TAPSE. Conclusions In patients with MVP referred to mitral valve repair, LV volumes indexed by BSA are more sensitive markers of LV dilatation than LV diameters in both sexes, and show that women have more often dilated LVs than men before and after surgery. Though significant reverse remodeling is present in both sexes after mitral valve repair, women have more frequently low LV EF and GLS than men after surgery. These findings call for use of sex-specific thresholds in the assessment of LV size and function when timing surgery in patients with MVP.Figure 1.LV size and function Figure 2.LV dilatation and dysfunction