[Risk of perioperative mortality and complications following biological aortic valve replacement in elderly patients: stented vs unstented bioprotheses].

Recently published studies suggest that the hemodynamic advantage of stentless bioprostheses in comparison to stented bioprostheses positively influence the long-term survival after aortic valve replacement. However, the more complex and time consuming implantation technique may increase the risk of operative death. Between April 1996 and September 2000, 201 patients with the mean age of 75 ± 5 years underwent aortic valve replacement (AVR) with a stentless Medtronic Freestyle Bioprothesis (FP) and 166 patients with a mean age of 77 ± 5 years received a stented Medtronic Mosaic Biopros thesis (MP). Patients requiring concomitant procedures other than coronary artery bypass grafting (CABG) were excluded. The operative mortality was 3.5% after AVR with the FP and 6% after AVR with the MP. Multiple logistic regression analysis considering the different patient populations revealed no increased risk of operative death after AVR with FB (p = 0.46). Previously heart operations (p = 0.046) and emergency operation (p = 0.022) were risk factors for operative death after AVR with the biological bioprostheses. The risk for postoperatively neurological impairment (p = 0.15) and other complications (p = 0.46) was furthermore not increased after implantation of a Freestyle stentless valve. The risk of delayed mobilization (p < 0.001) was 2.4-fold increased for patients after AVR with the Freestyle valve. A positive influence on survival due to the implantation of a stentless Freestyle valve could not be shown within the observed period. However, in spite of the more complex and time-consuming operation technique, the risk of operative death and postoperative complications is not increased after aortic valve replacement with the stentless FB.