The medtronic intact porcine valve: ten-year clinical review

OBJECTIVE: Our objective was to assess the long-term mortality and morbidity associated with the Medtronic Intact valve (Medtronic, Inc, Minneapolis, Minn). METHOD: Between 1983 and 1996, 447 patients (280 men and 167 women) received 466 Intact valves: 280 aortic, 156 mitral, and 30 tricuspid. The mean age was 57 years (median 63 years), with 45% younger than 60 years. The mean New York Heart Association class was 3.1. The follow-up was 98% complete and extended for 39 months (1-154 months) and 1324 patient-years. There were 32 valves at risk at 10 years after implantation. Doppler echocardiography was performed whenever possible in patients followed up for longer than 4 years (mean 8 years) after implantation. RESULTS: Ten-year overall actuarial survival was 30% +/- 6% (14% +/- 7% for New York Heart Association classes IV-V and 39% +/- 8% for classes I-III). At 10 years freedom from infective endocarditis was 92% +/- 3%, freedom from thromboembolism was 80% +/- 5%, and freedom from nonstructural valve deterioration was 95% +/- 2%. Ten-year freedom from explantation was 64% +/- 6%, freedom from valve-related events was 51% +/- 6%, and freedom from valve-related death was 88% +/- 3%. There were 26 examples of structural valve deterioration, mainly caused by leaflet calcification (in 17 cases) and by buttress detachment (in 6 cases). In the aortic position at 10 years freedom from structural valve deterioration was 81% +/- 9%, but with only 1 event in patients older than 40 years (freedom 92% +/- 8%) and 100% freedom in patients older than 60 years. There was also 100% freedom from structural valve deterioration in the tricuspid position. In the mitral position freedom was 65% +/- 8%, with no significant difference between age groups. CONCLUSION: The Intact valve provides superior results in the aortic position in patients older than 40 years and in the tricuspid position at all ages.