Effect of sex and surgical incision on survival after isolated primary mitral valve operations

OBJECTIVES Multiple studies have suggested that women have worse outcomes than men following mitral valve (MV) surgery—most of those studies reported on conventional sternotomy (CS) MV surgery. Therefore, we aimed to explore whether or not the minimally invasive mitral valve surgery (MIMVS) approach might mitigate a worse survival in women following MV surgery. METHODS We identified patients with isolated primary MV operations with or without tricuspid valve repair performed between 2007 and 2019. Patients were propensity score-matched across the MIMVS and CS surgical approaches. Sex was excluded from the matching process to discern whether female patients had a different likelihood of receiving minimally invasive surgery than males. A Cox proportional hazards model was fitted in the matched cohort and adjusted for the imbalance in baseline characteristics using the propensity score. RESULTS Of 956 patients (417 MIMVS, 539 CS; 424 females), the matched set comprised 342 pairs (684 patients; 296 females) of patients who were well balanced across MIMVS and CS groups with regard to preoperative clinical characteristics. We observed a 47/53% female/male ratio in the CS group and a 39/61% in the MIMVS group, P = 0.054. In both matched groups, women were older than males. A Cox model adjusted for propensity scores showed no survival difference with sex, surgical type or interaction. CONCLUSIONS Women present to the surgical team at an older age. They appear less likely to be considered for a MIMVS approach than men. Neither sex nor surgical approach was associated with worse survival in a matched sample.