Minimal Access Versus Sternotomy for Complex Mitral Valve Repair: A Meta-Analysis

Background. There is high demand for minimally invasive mitral valve repair; however, it is unclear whether the minimally invasive approach provides the same performance as conventional sternotomy in a context of complex mitral valve disease. Here, we compared outcomes of minimally invasive and sternotomy procedures for bileaflet and Barlow's mitral valve disease. Methods. We performed a pooled meta-analysis of studies reporting early and late follow-up of mitral valve repair for complex mitral valve regurgitation. The primary outcome was moderate mitral valve regurgitation recurrence and need for reoperation. Secondary outcomes included operation time, reopening for bleeding, associated tricuspid procedures, failed repair, and inhospital mortality. Incidence rates were calculated for long-term follow-up. Effect estimates were calculated as incidence rates with 95% confidence intervals. When Kaplan-Meier curves were available, event rates were estimated from the curves with Plot Digitizer software; otherwise, reported event rates were used to calculate incidence rates. Results. Eighteen studies including 1905 patients (654 minimally invasive and 1251 sternotomy) with a mean follow-up of 51.6 months (range, 14 to 138) were metaanalyzed with a random model. There were no significant between-group differences in moderate mitral valve regurgitation recurrence and reoperation (minimally invasive vs sternotomy, 1.7% [95% confidence interval, 1.0% to 2.9%] vs 1.3% [95% confidence interval, 0.9% to 1.8%], P = .22). Patients in the minimally invasive group were exposed to significantly longer cross-clamp and cardiopulmonary bypass times (P < .01); however, there were no additional between-group differences in secondary outcomes. Conclusions. This meta-analysis has demonstrated that minimally invasive and sternotomy approaches produce comparable results for complex mitral valve repair. (C) 2020 by The Society of Thoracic Surgeons