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.