Initial clinical experience with minimally invasive surgical aortic valve replacement

BACKGROUND The mini-sternotomy approach is increasingly used in aortic valve surgery. However, the advantages are still a matter of discussion. The aim of this study was to compare the postoperative outcome in patients undergoing elective aortic valve operation, either through mini-sternotomy or conventional sternotomy. METHODS We included 317 patients who were treated for their aortic valve, 63 patients underwent a minimally invasive aortic valve replacement (mini-AVR) and 254 patients underwent a full-sternotomy AVR. Patients with endocarditis, those who underwent previous cardiac surgery and those who required a concomitant procedure were excluded from the analysis. The method of matching weights according to propensity score was used to adjust for differences between the two treatment groups, and outcomes were compared. RESULTS The mediastinal drainage was significantly lower at 6, 24 hours and total after mini-AVR procedure than after full-sternotomy AVR (median: 373 vs 499ml, P<0.001). However, the number of patients receiving packed red blood cells transfusion was similar. Overall, the hospital mortality was lower in the fullsternotomy group, 0% vs 3.2%, P=0.039. No difference was found in the median hospital length of stay, perioperative myocardial infarction, postoperative incidence of new pacemaker implantation, stroke, prolonged mechanical ventilation and mediastinitis. No patients in the mini-AVR group experienced paravalvular leakage. Mid-term survival resulted in no difference between the treatment groups at 4-year (90.5% vs. 95.2%), P=0.75. CONCLUSIONS Although the minimally invasive surgery for AVR may increasingly be applied, our initial experience calls for a careful approach of adapting this procedure.