Propensity Score-Matched Analysis of Minimally Invasive Aortic Valve Replacement

Background: Right mini-thoracotomy and partial sternotomy are widely recognized as effective approaches in minimally invasive aortic valve replacement (AVR). The aim of this study was to evaluate the objective benefits of the respective approaches compared to the conventional approach. Methods and Results: A retrospective analysis was performed in 282 consecutive patients who underwent isolated and initial AVR at a single cardiovascular institute between May 2007 and December 2012. Mini-thoracotomy and partial sternotomy were performed in 62 (22%) and in 26 patients (9%), respectively. Propensity score matching produced 36 (mini-thoracotomy vs. full sternotomy) and 24 (partial sternotomy vs. full sternotomy) well-matched pairs. Compared to the conventional approach, mini-thoracotomy was associated with significantly shorter operative time (235 +/- 35 min vs. 272 +/- 73 min; P=0.009), lower prevalence of blood transfusion (42%, 15/36 vs. 67%, 24/36; P=0.025), and significantly shorter intensive care unit and postoperative hospital stay (1.4 +/- 0.8 days vs. 2.2 +/- 1.1 days, P=0.001; and 13.3 +/- 6.5 days vs. 21.5 +/- 10.3 days, P=0.001; respectively). There were no significant differences in operative and postoperative data between the partial sternotomy and full sternotomy groups. Conclusions: The objective benefits of right mini-thoracotomy included early rehabilitation and lower prevalence of blood transfusion. Significant advantages of partial sternotomy were not found.