title: Hemodynamic and clinical outcomes with the Biocor valve in the aortic position: an 8-year experience.
abstract: OBJECTIVE
  The aim of this study was to analyze the 8-year experience, survival, prosthetic complications, and hemodynamics of patients who received the Biocor valve, a new-generation tissue valve, in the aortic position.
  
  
  METHODS
  From May 1992 through May 2001, 257 consecutive patients (129 women and 128 men; mean age, 75 +/- 6 years; age range, 45-91 years) received 258 aortic Biocor porcine prostheses. One female patient who received 2 Biocor valves in the aortic position during 2 consecutive operations was entered twice in the statistical analysis. Twelve (4.6%) patients had previous aortic valve operations. Preoperatively, 82 (32%) patients were in New York Heart Association functional class III or IV. Associated surgical procedures included coronary artery bypass grafting in 56 (21.7%) patients, aortic annular enlargement or aortoplasty in 20 (8%) patients, and others in 8 (3%) patients. Echocardiography was performed in the majority of long-term survivors (91.6%). Follow-up included 1215 patient-years and was 100% complete, with a median time of 5 patient-years (range, 0.4-10.5 years).
  
  
  RESULTS
  There were 16 (6.2%) early deaths. According to a univariate analysis, New York Heart Association functional class III or IV, concomitant procedures, ejection fractions of less than 40%, and urgent operations were identified as significant perioperative risk factors. At follow-up, 75 patients died; 8-year actuarial Kaplan-Meier survival was 48% +/- 5%. At 8 years, the actuarial freedom from valve-related death was 92% +/- 2.6%, the freedom from thromboembolism was 93% +/- 2%, the freedom from anticoagulant-related hemorrhage was 95% +/- 2%, the freedom from endocarditis was 99% +/- 0.6%, the freedom from paravalvular leak was 96% +/- 1.5%, the freedom from all valve-related complications was 78% +/- 4.5%, and the freedom from structural valve deterioration was 95% +/- 3.7%. At 8 years, the actuarial freedom from structural valve deterioration was 89% +/- 10% and 95.8% +/- 4% in patients younger and older than 65 years, respectively. At 10 years, in patients older than 65 years, the actual freedom from structural valve deterioration was 97.9% +/- 2.1%, and the freedom from reoperation was 97% +/- 1.3%. New York Heart Association status was I or II in 90% of patients at the end of follow-up. The mean echocardiographic follow-up time was 4.6 +/- 2 years. By using Doppler echocardiography, the peak and mean transprosthetic gradients were determined to be 30.8 +/- 9.3 mm Hg and 16.6 +/- 5.3 mm Hg, respectively. Mean mass/volume ratio and left ventricular end-diastolic volume were 1.37 +/- 0.17 g/mL and 63.4 +/- 22.6 mL/m(2), respectively. The majority of patients showed a persistent left ventricular hypertrophy.
  
  
  CONCLUSIONS
  The Biocor is an effective bioprosthesis with a low incidence of valve-related complications comparable with that of other second-generation bioprostheses. This stented porcine prosthesis provides satisfactory results in terms of hemodynamics, valve durability, and freedom from reoperation.
authors.affiliation: Department of Cardiovascular Surgery, University of Padua Medical School, Padua, Italy.tomaso.bottio@unipd.it
authors.forename: Tomaso
authors.initials: T
authors.lastname: Bottio
authors.forename: Giulio
authors.initials: G
authors.lastname: Rizzoli
authors.forename: Gaetano
authors.initials: G
authors.lastname: Thiene
authors.forename: Georgios
authors.initials: G
authors.lastname: Nesseris
authors.forename: Dino
authors.initials: D
authors.lastname: Casarotto
authors.forename: Gino
authors.initials: G
authors.lastname: Gerosa
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001022:Aortic Valve Insufficiency / Q000000981:diagnostic imaging / Q000401:mortality / Q000601:surgery*; D001024:Aortic Valve Stenosis / Q000000981:diagnostic imaging / Q000401:mortality / Q000601:surgery*; D001705:Bioprosthesis; D015331:Cohort Studies; D016001:Confidence Intervals; D015150:Echocardiography, Doppler; D005260:Female; D005500:Follow-Up Studies; D006350:Heart Valve Prosthesis; D019918:Heart Valve Prosthesis Implantation / Q000379:methods / Q000401:mortality; D006439:Hemodynamics / Q000502:physiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D008991:Monitoring, Physiologic / Q000379:methods; D011183:Postoperative Complications / Q000401:mortality; D011336:Probability; D011474:Prosthesis Design; D011475:Prosthesis Failure; D012189:Retrospective Studies; D018570:Risk Assessment; D016019:Survival Analysis; D013997:Time Factors