Launching a program of minimally invasive mitral valve surgery

Aim: To evaluate the learning curve of minimally invasive mitral valve surgery (MVS). Procedure related times and complexity of mitral valve surgery were retrospectively analysed after establishing this surgical technique. Method: The first 300 patients operated at our center through an endoscopically enhanced MVS using a right anterolateral mini-thoracotomy and femoral cannulation, were compared for the following: perioperative times, mitral valve pathologies and reconstructive techniques. The underlying mitral valve pathologies were: degenerative (n = 279, 93%), ischemic (n = 3, 1%), rheumatic (n = 12, 4%), endocarditis (n = 5, 1.7%). All patients suffered from severe mitral regurgitation (3.2 ± 0.5) with a maintained ejection fraction of 60.2 ± 8.5%. Results: There were no early deaths in this cohort. The overall repair rate was 95.3%. When rheumatic pathologies were excluded, repair rate improved to 98.2%. Table 1 shows significant reduction of the operating, – the ECC and the cross clamp-time (analysed in groups of 100 patients), as well as an increase in the complexity of procedures performed e.g. implantation of neo-chordae to AML and PML. Table 1: Overall Analysis of Improvement 0 – 100 patients B vs. D p value 101 – 200 patients D vs. F p value 201 – 300 patients OP time [min] 293 ± 56 p ≤0.01 234 ± 55 p = ns 232 ± 41 ECC time [min] 181 ± 40 p = 0.02 163 ± 46 p = ns 153 ± 27 AXC time [min] 114 ± 24 p = ns 108 ± 30 p = 0.04 97 ± 19 Annuloplasty 89 p = ns 96 p = ns 96 Leaflet resection post. 77 p = ns 81 p = ns 72 Cleft repair 2 p ≤0.01 18 p = ns 13 Alfieri plasty 2 p = 0.01 11 p = ns 7 Neo-chordae AML 2 p ≤0.01 16 p = 0.04 28 Neo-chordae PML 2 p = 0.03 14 p = ns 17 Conclusion: The learning curve for minimally invasive MVS shows an improvement with respect to the procedure related times and complexity of the reconstructive techniques.