Learning curve in minimally invasive mitral valve surgery with 3D video endoscopic visualization system.

Aim: To compare the intraoperative parameters of minimally invasive mitral valve surgery with 3D video endoscopic visualization and conventional surgery, as well as to evaluate the learning curves for performing mitral valve interventions through a right minithoracotomy and to determine the number of surgeries that are required to achieve comparable success.

Methods: 242 medical records of patients with isolated mitral valve disease admitted to the Federal Center of Cardiovascular Surgery (Penza) for elective cardiac surgery in the period from January 2019 to December 2022 were retrospectively reviewed. All patients were divided into two groups. Group 1 patients (n=120) underwent mitral valve surgery through a right minithoracotomy with 3D video endoscopic visualization. All surgeries were performed by one operator. Group 2 patients (n=122) underwent mitral valve surgery through median sternotomy.

Results: 54 (45%) patients in Group 1 and 57 (46.7%) in Group 2 underwent mitral valve annuloplasty. Chordal replacement of the anterior mitral leaflet and mitral valve annuloplasty was performed in 23 (19.2%) patients in Group 1 and in 25 (20.5%) patients in Group 2. Resection or plication of the posterior mitral leaflet was performed in 28 (23.3%) patients in Group 1 and 26 (21.3%) patients in Group 2. 15 (12.5%) patients in Group 1 and 14 (11.5%) patients underwent mitral valve replacement using mechanical valves. Both groups did not differ by the types of surgical interventions. Postoperative complications did not differ between the groups. There were no cases of deaths in Groups 1 and 2. Both groups did not differ by the time of surgery, myocardial ischemia and cardiopulmonary bypass after transversing the curve.

Conclusion: Minimally invasive mitral valve surgery with total endoscopic visualization is a method of choice for treating mitral valve disease. To transverse the learning curve and achieve similar intraoperative results, at least 120 similar interventions should be performed. Patient selection is of great importance when starting mastering minimally invasive approaches.

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