Mitral valve replacement is one of the most common heart valve surgeries in China. In recent years, with the increase in degenerative valve diseases, older patients, and the progress of anti-calcification technology of biological valves, the proportion of mitral valve biological valve replacement has been increasing year by year. After the damage of traditional mitral valve biological valves, re-operation of valve replacement with thoracotomy is required. However, the adhesion between the heart and sternum, as well as the damage caused by cardiopulmonary bypass and cardiac arrest, can cause significant trauma to elderly patients and those with multiple organ dysfunction, leading to increased mortality and complication rates. In recent years, interventional valve surgery, especially transcatheter valve-in-valve surgery, has developed rapidly. This procedure can correct the damaged mitral valve function without stopping the heart, but there are still many differences between its technical process and conventional aortic valve replacement surgery. Therefore, organizing and writing multicenter expert recommendations on the technical process of transcatheter valve-in-valve surgery for damaged mitral valve biological valves is of great significance for the training and promotion of this technology.

Objective    To compare the efficacy and safety of mitral valvuloplasty via minimally invasive approach with those of mitral valvuloplasty via traditional median sternotomy. Methods    A total of 1 221 patients undergoing mitral valvuloplasty from January 2015 to August 2018 in Guangdong Provincial People's Hospital were analyzed retrospectively, including 721 males and 500 females, with an average age of 47.2±15.1 years. According to the different surgical methods, they were divided into a study group (n=654), who received mitral valvuloplasty via the totally thoracoscopic approach, and a control group (n=567), who received mitral valvuloplasty via traditional median sternotomy. Clinical data, surgical results, and perioperative outcomes of the two groups were compared. Results    There was no significant difference in preoperative general data between the two groups (P>0.05). Compared with the control group, the study group had longer cardiopulmonary bypass time and aortic cross-clamping time (146.7±42.4 min vs. 122.7±30.6 min, 96.2±32.7 min vs. 78.3±23.8 min, both P=0.000), and shorter total operation time (227.4±55.3 min vs. 238.1±56.4 min, P=0.001). There was no significant difference in the incidence of secondary cross-clamping and mitral valve replacement between the two groups (3.7% vs. 2.6%, P=0.312; 1.7% vs. 1.4%, P=0.690). The blood transfusion rate and the incidence of respiratory tract infection and postoperative poor wound healing were lower (13.0% vs. 24.5%, 2.1%vs. 18.0%, 1.5% vs. 5.3%, all P=0.000) and the postoperative hospital stay was shorter (6.2±4.4 d vs. 11.5±8.8 d, P=0.000) in the study group. There was no significant difference in hospitalization expense between the two groups (95 847.9±31 322.0 yuan vs. 99 673.1±47 930.3 yuan, P=0.149). Within 30 d after surgery, 1 patient died in the study group and 4 patients died in the control group. Before discharge, there were 4 and 5 patients with severe mitral valve regurgitation in the study group and the control group, respectively. Conclusion    Compared with mitral valvuloplasty via traditional median sternotomy, minimally invasive mitral valvuloplasty is superior in shortening operation time and postoperative hospital stay, lowering blood transfusion rate, and reducing postoperative complications, which can achieve better clinical outcomes.