Redo versus primary minimally invasive mitral valve surgery: results from a multicenter registry.

BACKGROUND: redo mitral valve (MV) surgery is associated with increased perioperative risk, mainly related to repeat median sternotomy. Minimally invasive mitral valve surgery (MIMVS) has emerged as an alternative strategy, with excellent results reported in primary procedures; however, its adoption in redo setting remains limited. This study aimed to compare early outcomes of redo versus primary MIMVS in a large multicenter registry. METHODS: all consecutive patients undergoing MIMVS between 2015 and 2024 at seven high-volume centers were retrospectively analyzed. Patients were divided in two groups: non redo patients and patients with at least one previous cardiac surgery procedure through median sternotomy The primary endpoint was perioperative mortality. RESULTS: 1,694 patients were included, 158 (9.3%) had received previous cardiac surgery. Redo patients presented a significantly higher preoperative risk profile, with higher EuroSCORE II (7.1% vs 1.3%, p<0.001) and a greater burden of comorbidities. They were more likely to undergo MV replacement and concomitant tricuspid valve surgery. No significant differences were observed in intraoperative complications. Postoperative outcomes and in-hospital mortality, were comparable between groups. CONCLUSIONS: redo patients arrive at surgery with a significantly higher risk profile when compared to patients undergoing primary MV surgery. Despite that, our analysis on MIMVS patients shows no differences in terms of peri-operative mortality and main complications between groups.