Mechanical versus biological heart valves: a ten-year comparison in a single centre

Between January 1977 and December 1986, 1606 Bjørk-Shiley tilting disc prostheses (BS) and 1346 Carpentier Edwards porcine prostheses (CE) were implanted in 1300 and 1156 patients, respectively, at the same institution. During the time of implantation, both valves have developed: the BS through standard disc and convexo-concave to monostrut, and the CE valves from standard to supra-annular. Newer valve types were used where applicable as they became available. Preoperative status in respect of age and cardiac rhythm were similar. There were significantly more females (64% BS: 54% CE, P less than 0.001); worse NYHA grade (74% Grade 111 and IV-BS: 56% 111 and IV-CE, P less than 0.001) more closed heart surgery (26% BS: 18% CE, P less than 0.001) and more previous open heart surgery (11.6% BS: 8.9% CE, P less than 0.001) in the BS group. All BS patients were anticoagulated and 49% of mitral CE patients and 7% of aortic CE patients were anticoagulated. There was no significant difference between the two groups in hospital mortality (BS 7.2%: CE 6.3%), late mortality (BS 2.5%/patient year: CE 3.2%/patient year) overall incidence of systemic embolism (BS 1.3%/patient year: CE 1.4/patient year), prosthetic valve endocarditis (BS 0.7%/patient year: CE 0.9%/patient year), valve failure (BS 0.5%/patient year: CE 0.9%/patient year) or peri-prosthetic leak (BS 1.2%/patient year: CE 1.3%/patient year). The incidence of systemic embolism in the aortic position was lower with the BS prosthesis (BS 0.2%/patient year: CE 1.2%/patient year, P less than 0.02).(ABSTRACT TRUNCATED AT 250 WORDS)