Background and aim of the study: The study aim was to review the long-term results of mitral valve replacement (MVR) with the Biocor“ porcine bioprosthesis, in order to investigate patient survival and valve-related complications.
Methods: Data were presented for 546 patients (320 females, 226 males; mean age 49.2 ± 17.1 years) who underwent MVR with the Biocor porcine bioprosthesis between March 1983 and December 2000. Preoperatively, rheumatic fever was present in 42.3% of patients. Associated procedures were performed in 179 patients (32.7%), and myocardial revascularization in 54 (9.9%). Preoperatively, 41.9% of patients were in NYHA class IV. Postoperative follow up was conducted by telephone interviews, questionnaires, or examination of hospital records.
Results: The hospital mortality was 9.5% (n = 52); of these patients, 30 died after their first MVR and 22 after mitral reoperation. Mortality after isolated MVR was 7.6%.

The total follow up was 2,148.9 patient-years, and actuarial survival was 45.0 ± 15.8% at 15 years. Freedom from structural valve deterioration (SVD) was 51.8 ± 13.8% for patients aged <50 years, 88.7 ± 5.1% for those aged 51-60 years, and 84.0 ± 9.8% for those aged 61-80 years. The incidence of prosthetic valve endocarditis was low, with 88.8 ± 6.1% non-recurrence in 15 years. Freedom from reoperation was 33.9 ± 10.4%, and from thromboembolism was 82.3 ± 15.0%. Freedom from valve-related mortality was 80.7 ± 12.5% during a 15-year period.
Conclusion: The 15-year clinical results with the Biocor porcine bioprosthesis in the mitral position were excellent in a young, predominantly rheumatic, patient population which, preoperatively, was in a grave clinical condition. The incidence of valve-related complications was low, as was that of SVD in patients aged >50 years.

The Journal of Heart Valve Disease 2006;15:763-767