Medtronic intact porcine bioprosthesis experience to twelve years

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 replace-ment 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. (C) 2001 by The Society of Thoracic Surgeons.