12-YEAR FOLLOW-UP WITH THE SORIN PERICARBON BIOPROSTHESIS IN THE MITRAL POSITION

Background and aims of the study: The aim of this study was to evaluat e the long-term follow up of the Pericarbon pericardial bioprosthesis implanted in the mitral position. Methods: Between January 1985 and Ja nuary 1991, 78 patients (26 males, 52 females; mean age 56.9 +/- 7.8 y ears) underwent isolated mitral valve replacement with a Pericarbon va lve. All bioprostheses were size 29 mm and implanted by the same surge on. Results: Total follow up was 663.2 pt-years and it was 97% complet e. Early mortality was 1.3% (1/78); two minor cerebral embolisms were observed as early complications. At 12 years the overall survival rate was 85.0 +/- 4.2% and valve-related survival 93.1 +/- 3.0%; freedom f rom embolic events was 83.0 +/- 4.5% and from endocarditis 98.7 +/- 1. 3%. Freedom from primary tissue failure was 56.8 +/- 6.6%; it was 86.3 +/- 7.5% in patients aged >60 years and 36.8 +/- 8.2% in younger pati ents. There were 27 reoperations, 26 for primary tissue failure, one f or endocarditis. Comparison between basal and follow up echocardiograp hic studies showed a significant stenotic deterioration of the biopros thesis and a negligible incidence of regurgitation. Morphological find ings of explanted bioprostheses were characterized by stenotic and dif fuse microcalcification, but no tissue tear was observed. Conclusions: These results confirm that the Pericarbon bioprosthesis is structural ly safe and free from the fatigue problems which afflicted the first a nd second generation of pericardial valves. As with other tissue valve s, the rate of calcification is age-dependent, suggesting preferential use of the Pericarbon prosthesis in elderly people.