title: Aortic valve replacement with the Toronto SPV: long-term clinical and hemodynamic results.
abstract: 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.
authors.affiliation: Division of Cardiovascular Surgery, The Toronto General Hospital, 200 Elizabeth Street, EN 14-222, Toronto, Ontario, Canada M5N 2C4.
authors.forename: Göran
authors.initials: G
authors.lastname: Dellgren
authors.forename: Christopher M
authors.initials: CM
authors.lastname: Feindel
authors.forename: Joanne
authors.initials: J
authors.lastname: Bos
authors.forename: Joan
authors.initials: J
authors.lastname: Ivanov
authors.forename: Tirone E
authors.initials: TE
authors.lastname: David
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001021:Aortic Valve / Q000000981:diagnostic imaging / Q000601:surgery*; D001022:Aortic Valve Insufficiency / Q000401:mortality / Q000601:surgery; D001024:Aortic Valve Stenosis / Q000401:mortality / Q000601:surgery; D001705:Bioprosthesis; D015150:Echocardiography, Doppler; D004696:Endocarditis / Q000209:etiology / Q000401:mortality; D005260:Female; D005500:Follow-Up Studies; D019918:Heart Valve Prosthesis Implantation; D006439:Hemodynamics / Q000502:physiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D009017:Morbidity; D009864:Ontario / Q000453:epidemiology; D011183:Postoperative Complications / Q000209:etiology / Q000401:mortality; D011475:Prosthesis Failure; D012086:Reoperation; D012720:Severity of Illness Index; D016019:Survival Analysis; D013923:Thromboembolism / Q000209:etiology / Q000401:mortality; D016896:Treatment Outcome