Minimally invasive right thoracotomy approach for mitral valve surgery in patients with previous sternotomy: A single institution experience with 173 patients

Objective: This study presents a review of our experience with minimally invasive mitral valve surgery (MIMVS) in patients with a previous cardiac procedure performed through a sternotomy over a 10-year period. Methods: From November 2003 to August 2013, 173 patients (age 61.3 +/- 12.4 years) underwent reoperative MIMVS through a right minithoracotomy. Previous operations were coronary artery bypass grafting (n = 49; 28.6%), a mitral valve procedure (n = 120; 70.1%), an aortic valve procedure (n = 32; 18.7%), and other operations (n = 14; 8.1%). The mean euroSCORE was 11.2 +/- 3.8. The time to redo surgery was 6.9 +/- 4.2 years. Results: Procedures were performed with central aortic cannulation in 55 patients (31.7%) and peripheral cannulation in 118 (68.3%). A transthoracic clamp was used in 58 patients (33.5%), an endoaortic balloon in 72 (41.6%), hypothermic ventricular fibrillation in 23 (13.2%), and beating heart in 20 (11.5%). Mean cardiopulmonary bypass and crossclamp times were 160 +/- 58 minutes and 82 +/- 49 minutes, respectively. Mitral repair was performed in 53 patients (30.6%). Forty-three patients (24.7%) had an additional cardiac procedure. Conversion to sternotomy was necessary in 2 patients (1.1%) and reoperation for bleeding in 11 patients (6.3%). Thirty-day mortality was 4.1% (n = 7). Major morbidities included stroke (n = 11; 6%) and new-onset dialysis requirement (n - 4; 2.3%). The mean blood transfusion requirement was 1.4 +/- 1.1 units. Mean follow-up was 3.3 +/- 2.6 years. Survival at 1, 5, and 10 years was 93.1% +/- 1.9%, 87.5% +/- 2.7%, and 79.7% +/- 3.8%, respectively. Conclusions: Reoperative mitral valve surgery can be safely performed through a right minithoracotomy with good early and late outcomes. The avoidance of extensive surgical dissection, optimal valve exposure, and low blood transfusion are the main advantages of this technique.