Conventional sternotomy versus right mini-thoracotomy versus robotic approach for mitral valve replacement/repair: insights from a network meta-analysis

INTRODUCTION: Minimally invasive cardiac surgery (MICS) through right mini-thoracotomy as well as robotic surgery has emerged for the last decade for mitral valve surgery. However, their risks and benefits are not fully understood yet. Thus, we conducted a network meta-analysis comparing the early- and long-term outcomes of mitral valve surgery via the conventional sternotomy, MICS, and robotic approaches. EVIDENCE ACQUISITION: MEDLINE and EMBASE were searched through November 2020 to identify randomized controlled trials (RCTs) and propensity-score matched (PSM) trials that investigated early- and long-term outcomes after mitral surgery via the conventional sternotomy, MICS, and robotic approaches. A subanalysis focusing on only subjects who initially underwent mitral valve repair was also conducted. EVIDENCE SYNTHESIS: Our systematic literature search identified two RCTs and 19 PSM studies. MICS was related to significant risk reductions of permanent pacemaker implantation, surgical site infection, and transfusion compared to the sternotomy approach. The robotic approach was associated with a significant increase in re-exploration for bleeding compared to sternotomy. The subanalysis showed that MICS was associated with a significant increase requiring mitral valve reoperation compared to the sternotomy approach (hazard ratio 7.33 [95% CI: 1.54-34.97], P=0.012), while no significant difference was observed between the sternotomy and the robotic approach. CONCLUSIONS: Our network meta-analysis demonstrated that MICS was associated with better short-term outcomes compared to the sternotomy approach. Mitral valve reoperation was more frequent with MICS compared with the sternotomy approach after mitral valve repair, while no difference was observed between the sternotomy and robotic approaches.