10-year experience with the Biocor porcine bioprosthesis in the mitral position

One hundred and thirty-seven consecutive patients had mitral valve replacement between January 1983 and January 1993 with Bicor porcine bioprosthesis. Concomitant cardiac procedures were performed in 37% (51/137). Mean age was 63 years. Follow up was 98% complete at a mean of 53 months. Early mortality was 13% (18/137). Within the 10-year follow up another 34 patients died, 21 due to cardiac and three to valve related causes. Overall survival at 10 years as 54.7 +/- 4.9%, and freedom from valve related mortality 94.9 +/- 2.8%. Functional class improved in all surviving patients with 84% being in NYHA class I or II at the end of the tenth year. There were 10 reoperations, three for structural valve deterioration (SVD), three for non-structural valve dysfunction (non-SVD) and four because of prosthetic valve endocarditis (PVE). Actuarial freedom from reoperation for all causes was 78.9 +/- 9.2%. None of the patients were on long term anticoagulation at hospital discharge but 57% received chronic anticoagulant treatment at the end of the 10-year follow up. Embolism occurred in 13 patients (2.5%/pty, fatal 0.4%/pty). Three patients had anticoagulant related hemorrhage (0.6%/pty, fatal 0.2%/pty). Doppler echocardiography was carried out in 52% within the last three years of follow up. Actuarial freedom from SVD (confirmed at reoperation or by echocardiography) was 80.3 +/- 9.8%. At 10 years 93.2 +/- 2.8% were free from PVE. The incidence of total mortality and morbidity was 5.9%/pty (fatal 0.8%/pty) with an actuarial freedom of 59.6 +/- 8.8% from all valve related complications.(ABSTRACT TRUNCATED AT 250 WORDS)