Medium-term results of stentless bioprostheses for aortic valve replacement results in a series of 97 patients.

Stentless bioprostheses have been described as valve substitutes of interes t for aortic valvular replacement. We studied 97 consecutive patients with a mean age of 72.2 years (40-84) wh o underwent aortic valvular replacement with 80 Toronto SPV and 17 Freestyl e prostheses. Operative mortality was 6.2. With a mean follow-up of 19 +/- 10 months (1-4 6), 87.2% of the surviving 86 patients underwent an echocardiography perfor med by the same operator. Mean gradient was 10.9 +/-3.6 mmHg (4.2-22.6) and effective orifice area was 1.8 +/-0.5 cm(2) (0.8-3.0) for the 75 controlle d stentless valves. The best haemodynamic data were obtained with the 25 mm diameter prostheses. One asymptomatic partial dehiscence was observed duri ng monitoring. None of the 15 detected aortic leaks was significant. We obs erved a significant reduction of the ventricular mass in 41 patients who ha d undergone pre- and postoperative evaluation (p < 0.0014). Overall surviva l was 86.8 +/-4.4% at 2 years. Stentless bioprostheses offered satisfactory haemodynamic results in our se ries. They however require an implantation technique learning curve as well as a thorough knowledge of the aortic root anatomy and physiology.