Propensity-matched analysis of two port approach versus three port approach for totally thoracoscopic mitral valve replacement

BACKGROUND: To objectively evaluate the feasibility, safety, effectiveness and short-term outcome of totally thoracoscopic mitral valve replacement via two port approach, we conducted a retrospective study comparing two port approach with three port approach for mitral valve replacement. METHODS: Data for all thoracoscopic mitral valve replacement were analyzed from Guangdong Cardiovascular Institute between January 1, 2016 and December 31, 2017. To account for selection bias between two port approach and three approach, one-to-one propensity score caliper matching without replacement was performed. The clinical data of the two groups were collected, including preoperative cardiac function, operative data, postoperative complications, and short-term outcome. RESULTS: A total of 330 patients who underwent totally thoracoscopic mitral replacement via two port or three port from January 1, 2016 to December 31, 2017 were enrolled (two-port group: n=103; three-port group: n=227). Propensity score matching resulted in 71 matched pairs with improved balance post matching in baseline covariates. The baseline differences between two groups were eliminated (P>0.05 for all baseline variables). The cardiopulmonary bypass time (min) (154.27±57.02 vs. 142.68±51.33 P=0.183) and the aortic cross-clamp time (min) (106.99±106.98 vs. 90.16±31.63 P=0.206) in the two-port group were not significantly different from those in the three-port group. No significant difference was observed between the two groups in mechanical ventilation time, duration of intensive care unit stay, or amount of postoperative chest drainage. No perioperative death or re-exploration for bleeding was found in either group. As for other postoperative complications, two groups had the similar rate of lung infection lung infection (1.41% vs. 1.33% P=1.000) or acute renal failure (1.41% vs. 1.41% P=1.000). CONCLUSIONS: No significant differences in cardiopulmonary bypass time, aortic cross-clamp time, overall operative time, perioperative mortality, or complications were observed between two-port and three-port totally thoracoscopic mitral valve replacement. Two-port totally thoracoscopic mitral valve replacement is a safe, effective, and feasible procedure for mitral valve replacement.