Impact and Outcomes of Failure Mode Following Mitral Valve Repair

OBJECTIVE: Mitral valve repair (MVr) is the standard of care for degenerative mitral regurgitation (MR). However, repair failure occurs, stemming either from progression of disease (non-technical failure, NTF) or suboptimal initial repair (technical failure, TF). This study assesses the impact and outcomes of failure mode in patients requiring reoperation after MVr. METHODS: A single-center retrospective analysis was conducted on patients reoperated for failed MVr for degenerative MR from 2014 to 2023. Failures requiring open surgical reintervention were classified as NTF or TF and outcomes were compared between groups. RESULTS: Among 237 patients undergoing reoperation for failed MVr, 42% (n=99) experienced TF, with 71% (n=70) of TF repairs originating from outside institutions. TF patients presented for reoperation earlier than NTF patients (mean 4.5 vs. 9.5 years, p<0.001). Early failure (<2 years) occurred in 52% of TF cases, and 39% of these had >mild MR on initial postoperative transesophageal echocardiogram. Re-repair was more common in TF (35.4%) vs. NTF (10.1%) (p<0.001), and re-repair was associated with reduced length of stay (5 vs. 8 days, p=0.001). Re-repair was associated with improved survival (p<0.001). CONCLUSIONS: Technical failure was a common and possibly avoidable mode of MVr failure amongst patients presenting for mitral reintervention at the author's institution, often due to significant residual MR at the index operation. When reoperation is required, re-repair, when feasible, is associated with favorable outcomes and should be pursued. Achieving residual MR that is mild or less at the time of repair is essential to optimize long-term outcomes.