title: Medtronic Intact porcine bioprosthesis experience to twelve years.
abstract: BACKGROUND
  The Medtronic Intact porcine bioprosthesis was further evaluated to determine the influence of zero-pressure glutaraldehyde fixation on structural valve deterioration (SVD).
  
  
  METHODS
  From 1986 through 1996, at three Canadian centers, 1,272 patients had 1,296 procedures: 836 aortic valve replacement (AVR), 332 mitral valve replacement (MVR), 14 tricuspid valve replacement, 3 pulmonary valve replacement, and 111 multiple valve replacements. The mean age of the patient population was 67 years (range 9 to 91 years). The total follow-up was 8,011 patient-years (mean 6.2 years).
  
  
  RESULTS
  The late mortality (overall) was 4.8% and 6.7% per patient-year for AVR with or without concomitant procedures, respectively; and 4.7% and 10.4% per patient-year for MVR, respectively. There were 51 cases of SVD (AVR 22 of 836; MVR 23 of 332; pulmonary valve replacement 1 of 3; and multiple valve replacement 5 of 111). The actuarial freedom from SVD at 12 years for AVR was 94.3%+/-3.3% for patients aged 61 to 70 years and 97.7%+/-1.1% for those more than 70 years; for MVR actuarial freedom from SVD at 12 years was 93.7%+/-3.9% for patients more than 70 years. The actual freedom at 12 years from SVD for AVR was 92.4%+/-3.1% for patients aged 51 to 60 years, 96.1%+/-2.1% for those 61 to 70 years, and 98.4%+/-0.7% for those older than 70 years; for MVR actual freedom from SVD at 12 years was 89.6%+/-3.2% for patients 61 to 70 years and 96.6%+/-3.4% for those more than 70 years.
  
  
  CONCLUSIONS
  The Medtronic Intact porcine bioprosthesis, formulated with tissue preservation at zero-pressure fixation, has encouraging freedom from structural failure.
authors.affiliation: Department of Surgery, University of British Columbia, Vancouver, Canada. wrej@interchange.ubc.ca
authors.forename: W R
authors.initials: WR
authors.lastname: Jamieson
authors.forename: M D
authors.initials: MD
authors.lastname: Lemieux
authors.forename: J A
authors.initials: JA
authors.lastname: Sullivan
authors.forename: I A
authors.initials: IA
authors.lastname: Munro
authors.forename: J
authors.initials: J
authors.lastname: Métras
authors.forename: P C
authors.initials: PC
authors.lastname: Cartier
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001021:Aortic Valve / Q000601:surgery; D001705:Bioprosthesis; D002170:Canada; D002423:Cause of Death; D002648:Child; D019544:Equipment Failure Analysis; D005260:Female; D005500:Follow-Up Studies; D006349:Heart Valve Diseases / Q000601:surgery*; D006350:Heart Valve Prosthesis; D006801:Humans; D008297:Male; D008875:Middle Aged; D008943:Mitral Valve / Q000601:surgery; D011183:Postoperative Complications / Q000401:mortality; D011474:Prosthesis Design; D011664:Pulmonary Valve / Q000601:surgery; D012086:Reoperation; D014261:Tricuspid Valve / Q000601:surgery