Minimally Invasive Trans-Axillary versus Full Sternotomy Mitral Valve Repair: A Propensity Score-Matched Analysis on Mid-Term Outcomes

Background and Objectives: Minimally invasive cardiac surgery is an established approach for the treatment of heart valve pathologies and is associated with excellent technical and early postoperative outcomes. Data from medium- and long-term longitudinal evaluation of patients who underwent mitral valve repair (MVr) through transaxillary approach (TAxA) are still lacking. The aim of this study is to investigate mid-term results in patients who underwent TAxA MVr. Materials and Methods: Prospectively collected data of patients who underwent first-time MVr for MV regurgitation between 2017 and 2022, were reviewed. A total of 308 patients received TAxA, while in 220 cases, traditional full sternotomy (FS) was performed. Concomitant aortic and coronary artery bypass grafting (CABG) procedures, infective endocarditis or urgent operations were excluded. A propensity match (PS) analysis was used to overcome preoperative differences between the populations. Follow-up data were retrieved from outpatients' clinic, telephone calls and municipal administration records. Results: After PS-matching, two well-balanced cohorts of 171 patients were analysed. The overall 30-day mortality rate was 0.6% in both cohorts. No statistical difference in postoperative complications was reported. TAxA cohort experienced earlier postoperative extubation (p < 0.001) with a higher rate of extubation performed in the operating theatre (p < 0.001), shorter intensive care unit (ICU) stay (p < 0.001), and reduced hospitalization with 51% of patients discharged home (p < 0.001). Estimated survival at 5 years was 98.8% in TAxA vs. 93.6% in FS cohort (Log rank p = 0.15). The cumulative incidence of reoperation was 2.6% and 4.4% at 5 years, respectively, in TAxA and FS cohorts (Gray test p = 0.49). Conclusions: TAxA approach for MVr was associated with low rates of in-hospital mortality and major postoperative complications being furthermore associated with shorter mechanical ventilation time, shorter ICU stay and reduced hospitalization with a higher rate of patients able to be discharged home. At mid-term, TAxA was associated with excellent survival and low rate of MV reoperation