Sex Differences in Pre- and Post-Surgical Left Ventricular Remodeling and Outcomes in Degenerative Mitral Regurgitation.

Background: Studies suggest that females have worse post-surgical left ventricular (LV) reverse remodeling and clinical outcomes than males in primary mitral regurgitation (MR). These studies were retrospective, used linear dimensions of the LV, and did not account for MR severity. This study is to determine if there are sex differences with respect to pre- and post-surgical LV remodeling and clinical outcomes.

Methods: There were 143 prospectively enrolled patients (60 ± 12yrs, males 70%) with primary MR who underwent pre- and post-surgical CMR evaluation. Clinical outcomes were ascertained by patient interview and chart review. Adverse outcomes were a composite of heart failure hospitalizations, need for reoperation, and death.

Results: MRV and MRF were independent predictors of pre-surgical LVEDV and post-surgical change in LVEDV and sex was not an independent predictor. For each 1ml increase in MRV there was an increase in pre-surgical LVEDV of 0.93ml for males and 1.0ml for females and a post-surgical decrease in LVEDV of 1.1ml for males and 1.0ml for females. Over a mean follow-up period of 3.3±2.6 years there were 10 (7%) patients with adverse events and no significant difference in the event rate between males and females (6 vs 11%, p=0.5).

Conclusion: In primary MR there were no sex differences in the degree of pre-surgical LV dilatation or post-surgical LV reverse remodeling. There were no sex differences in adverse clinical events. These findings highlight that males and females benefit similarly from mitral valve surgery and females should be referred for mitral valve surgery when appropriate.(Clinical Trials: NCT04038879, NCT03012178, NCT04051411).