Evaluation of minimal access proximal thoracic aortic surgery

Minimal access approaches in cardiac surgery and for procedures on the aortic valve began to develop in the 1990s. Several variations were performed in search of the most appropriate technique before the median ministernotomy was established. Despite limited exposure, difficult deairing or cardioplegia application and longer surgical times were described in the literature, surgeons believed that this technique would reduce surgical trauma and bleeding, improve chest stability, reduce pain and respiratory failure and shorten hospitalization and costs, while keeping mortality and morbidity low. The aim of this retrospective study was to review the techniques of minimal invasive surgery on the thoracic aorta in use in Heart Center Leipzig from 1998 to 2011 as well as the preoperative circumstances, intraoperative setup and early and late postoperative outcome of these patients. The results were to be integrated in the current literature and commented on. All 199 patients who underwent a procedure on the proximal aorta through minimal access incision were selected and included in this study. The procedures were completed with a standard surgical setup. Perioperative and intraoperative data were collected from surgical and discharge reports. Elective surgery was performed in 95.5% of the patients. 8.5% were redo procedures. Indication for surgery was dilatation of the proximal aorta in 92.5%, accompanied by pathology of the aortic valve in 87.9%. Access to the surgical site was L-type partial sternotomy in 59.7%. Cannulation for cardiopulmonary bypass was performed mostly through the ascending aorta or aortic arch (arterial line) and right atrium (venous line). Intermittent antegrade cardioplegia was delivered in all patients. Brain protection strategies for patients undergoing aortic arch replacement included hypothermic circulatory arrest and selective cerebral perfusion. Following procedures were performed: isolated aortic arch replacement (n=1); supracoronary ascending aorta replacement (isolated n=15, combined to aortic arch replacement n=8, combined to aortic valve replacement n=37 or combined to both n=10), and aortic root surgery (isolated aortic root replacement or repair n=95, aortic root replacement or repair combined to aortic arch replacement n=33). Cardiopulmonary bypass time was 123 ± 44 minutes. Conversion to full sternotomy was performed in 5 patients due to low cardiac output syndrome or bleeding. Thirty-day mortality was 5.0% (n=10) and ischemic stroke rate was 2.5% (n=5). Reoperation due to bleeding was performed on 13.1% (n=26). The estimated 10-year survival was 76 ± 4%. Clinical research to this subject is limited, based in studies with small populations and heterogenous procedures. Our study confirms the feasibility of minimal access proximal aortic surgery because neither inadequate exposure nor problems with deairing or cardioplegia were reported. Surgical times were shorter than described in the literature. Mortality, stroke, cardiac and sternal complication rates were low and comparable to the results in the literature. We consider that our higher reexploration rate of because of bleeding was caused primarily due to pathological coagulation state. We present the first long term results for minimal access proximal aortic surgery at 10 years. We consider that our results reflect better the risk inherent to minimal access proximal aortic surgery than studies with smaller cohorts but recognize it is limited by its retrospective form and heterogeneity of the reported procedures. Randomized prospective studies should bring more information about the safety of this procedure, but we support ministernotomy as a promising access for selected patients