The micro-mitral operation comparing the port-access technique and the transthoracic clamp technique

Background: Several minimally invasive approaches to the mitral valve have been described, including parasternal incision and right anterolateral thoracotomy. Material and Methods: Since September 1996, 58 patients underwent minimally invasive mitral valve surgery at our institution through a right anterolateral minithoractomy. Two different techniques were used for institution of cardiopulmonary bypass (CPB) and aortic clamping: in the Port-Access group (group A) patients had femoro-femoral cannulation with a special arterial cannula to introduce an endoaortic balloon clamp (n = 23). The second group (group B) of patients underwent femoro-femoral CPB as well in combination with a specially designed transthoracic aortic clamp (Chitwood technique, n = 35). Patients were assigned to either technique in a nonrandomized fashion. Demographics were similar in both groups. Results: In group A, 4 valves were replaced, 19 patients had mitral valve repair. In group B, 7 patients had valve replacement and 28 patients underwent mitral repair. Four patients in group A were converted to Chitwood technique due to endoclamp dysfunction. Operating time, CPB time, cross-clamp time, and postoperative blood loss were lower in group B (operating time 295 +/- 83 min vs. 236 +/- 63.9 min; CPB min 167.6 = 64.9 min vs. 137.6 +/- 38.2 min; cross-clamp time 105.9 +/- 51.7 min vs. 78.9 +/- 25.2 min; postoperative blood loss 584 +/- 428 mt vs. 323 +/- 209 mL [p < 0.05]). Clinical outcome regarding postoperative mechanical ventilatilation time, hospital stay and hospital mortality was not different between groups. Conclusions: Minimally invasive mitral valve procedures via right anterolateral minithoracotomy, including complex valve repair, can be performed successfully using either technique. However, the Chitwood technique provides better intraoperative handling with shorter operation time and less postoperative blood loss. Additionally, costs of a procedure are less using the Chitwood technique compared to the Port-Access technique.