Robotic-assisted versus minimally invasive mitral valve repair: a claims data analysis of clinical and cost outcomes.

Background: Minimally invasive mitral valve repair (Mini-MVr) and robotic-assisted MVr are alternatives to median sternotomy, offering benefits such as shorter recovery. However, cost comparisons between these two approaches remain unclear in Japan, where both are reimbursed equally. Our objective was to conduct a claims-based analysis in Japan to evaluate the inpatient costs as well as acute clinical outcomes between Mini-MVr and robotic-assisted MVr. Methods: We performed a retrospective analysis using the Medical Data Vision (MDV) claims database, covering 473 acute care hospitals in Japan. Patients who underwent MVr under general anesthesia from February 2019 to July 2023 were included. Clinical outcomes and costs were evaluated using the Diagnostic Procedure Combination codes. Results: Among 1,430 Mini-MVr and 110 robotic-assisted MVr patients, all robotic cases were performed in large-volume hospitals. The concomitant Maze procedure rates were similar between groups. Robotic-assisted MVr was associated with higher intraoperative transfusion rates and greater use of fibrin-based hemostatic agents. In-hospital mortality was low and similar (0.5% Conclusions: Robotic-assisted MVr was safe and comparable to Mini-MVr in terms of clinical outcomes and total inpatient costs, despite higher operative day costs. These findings support the feasibility of robotic-assisted MVr, particularly in high-volume centers.