Propensity-matched analysis of robotic versus sternotomy approaches for mitral valve replacement

Abstract

To compare early and medium-term outcomes between robotic and sternotomy approaches for mitral valve replacement (MVR). Clinical data of 1393 cases who underwent MVR between January 2014 and January 2023 were collected and stratified into robotic MVR (n = 186) and conventional sternotomy MVR (n = 1207) groups. The baseline data of the two groups of patients were corrected by the propensity score matching (PSM) method. After matching, the baseline characteristics were not significant different between the two groups (standardized mean difference < 10%). Moreover, the rates of operative mortality (P = 0.663), permanent stroke (P = 0.914), renal failure (P = 0.758), pneumonia (P = 0.722), and reoperation (P = 0.509) were not significantly different. Operation, CPB and cross-clamp time were shorter in the sternotomy group. On the other hand, ICU stay time, post-operative LOS, intraoperative transfusion, and intraoperative blood loss were shorter or less in the robot group. Operation, CPB, and cross-clamp time in robot group were all remarkably improved with experience. Finally, all-cause mortality (P = 0.633), redo mitral valve surgery (P = 0.739), and valve-related complications (P = 0.866) in 5 years of follow-up were not different between the two groups. Robotic MVR is safe, feasible, and reproducible for carefully selected patients with good operative outcomes and medium-term clinical outcomes.

Keywords: Mitral valve replacement; Propensity score matching; Robot; Sternotomy.

Fig. 1

Patient flow diagram

Fig. 2

Robotic mitral valve replacement. A Four robotic arms are docked to a patient’s right chest. From left to right: left instrument arm, camera arm, dynamic retractor arm, and right instrument arm. B The diseased mitral valve is excised. C Robotically seated bioprosthetic valve. D Robotically seated mechanical valve

Fig. 3

Absolute standardized mean differences

Fig. 4

The learning curve of robotic mitral valve replacement. A Operation time: y (min) = 412.52x^−41.04; r² = 0.623; P < 0.001. B CPB time: y (min) = 293.96x^−32.13; r² = 0.603; P < 0.001. C Cross-clamp time: y (min) = 203.26x^−24.39; r² = 0.631; P < 0.001. CPB cardiopulmonary bypass

Fig. 5

Comparison between the surgeon’s early and late experience of robotic MVR. A Operation time. B CPB time. C Cross clamp time. D ICU stay time. E Post-operative LOS. F Intraoperative transfusion. G Postoperative transfusion. H Intraoperative blood loss

Fig. 6

Time-to-event curves for clinical outcomes after matching. A All-cause mortality. B Redo mitral valve surgery. C Valve-related complications