Late Survival Is Improved After Redo Mitral Operation With Minithoracotomy Compared With Sternotomy

The long-term effectiveness of minithoracotomy over redo median sternotomy for reoperative mitral operation is not well described. Here we present long-term survival after reoperative mitral operation based on operative approach.Adults undergoing mitral valve operation with previous sternotomy by redo sternotomy and minithoracotomy were reviewed from our prospectively maintained institutional database from 1997 to 2022. Propensity score matching was performed to compare short- and long-term outcomes.Of 750 consecutive patients, thoracotomy was performed in 503 (67%). Median follow-up was 5.0 years (interquartile range, 0-23 years). Intraoperatively, sternotomy patients were more likely to have central aortic cannulation (205 of 223 [93%] vs 265 of 481 [56%]), cardioplegic arrest (220 of 223 [99%] vs 124 of 481 [26%]), and mitral valve replacement (190 of 223 [85%] vs 358 of 481 [74%]). Thoracotomy patients were older (63 ± 13 vs 58 ± 14 years) with elective presentation (387 of 503 [77%] vs 128 of 247 [52%]). Sternotomy patients were more likely to have endocarditis (52 of 247 [21%] vs 45 of 503 [9%], P < .001). At 10 years, thoracotomy patients experienced improved survival (52% ± 3% vs 46% ± 4%, P = .004). After propensity matching, 10-year survival was significantly higher for thoracotomy patients compared with sternotomy patients (60% ± 5% vs 42% ± 5%, P = .0006). The greatest difference in survival was at the first 6 months after operation (96% ± 1% vs 81% ± 3%, P < .001).For patients undergoing reoperative mitral valve operation, minimally invasive right anterior thoracotomy can significantly decrease risk of death in the first 6 months, with durable survival benefit out to 10 years. We present a large single-center series to suggest an important opportunity to durably improve outcomes after reoperative mitral operation through wider use of right minithoracotomy.