Objective: Long-term durability and hemodynamics of stentless valves are unknown. Therefore, this study was undertaken to evaluate long-term clinical and echocardiographic outcome after aortic valve replacement with the Toronto stentless porcine valve (SPV) bioprosthesis at our institution.
Methods: Between 1991 and 1998, the Toronto SPV was implanted in 255 patients (mean age, 63+/-11 years, range 22-83 years, 181 males and 74 females). Preoperative diagnoses were aortic stenosis (76%), aortic insufficiency (12%) and mixed lesion (12%). New York Heart Association class III and IV were present in 49% (126/255) of the patients preoperatively. Mean valve size implanted was 26.5+/-2.1mm and in addition 34% (86/255) of the patients had coronary artery bypass surgery.
Results: Early mortality was 0.8% (2/255). Actuarial survival at 7 years was 90+/-3%. At 7 years, the freedom from cardiac death was 98+/-2%; from valve-related death, 99+/-1%; from valve reoperation, 97+/-2%; from structural valve degeneration, 97+/-2%; from thromboembolism, 95+/-2%; and from endocarditis, 99+/-1%. At 7 years of follow-up, the transvalvular peak and mean pressure differences across the aortic valve measured with Doppler echocardiography was 9.6+/-5.1 and 3.6+/-2.0 mmHg, respectively.
Conclusions: The Toronto SPV has provided excellent clinical and hemodynamic results up until 7 years of follow-up.