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

Abstract

Between January 1977 and December 1986, 1606 Bjork-Shiley tilting discprostheses (BS) and 1346 Carpentier Edwards porcine prostheses (CE) wereimplanted in 1300 and 1156 patients, respectively, at the same institution.During the time of implantation, both valves have developed: the BS throughstandard disc and convexo-concave to monostrut, and the CE valves fromstandard to supra-annular. Newer valve types were used where applicable asthey became available. Preoperative status in respect of age and cardiacrhythm 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 andIV-CE, P less than 0.001) more closed heart surgery (26% BS: 18% CE, P lessthan 0.001) and more previous open heart surgery (11.6% BS: 8.9% CE, P lessthan 0.001) in the BS group. All BS patients were anticoagulated and 49% ofmitral CE patients and 7% of aortic CE patients were anticoagulated. Therewas 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%/patientyear) overall incidence of systemic embolism (BS 1.3%/patient year: CE1.4/patient year), prosthetic valve endocarditis (BS 0.7%/patient year: CE0.9%/patient year), valve failure (BS 0.5%/patient year: CE 0.9%/patientyear) 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 withthe BS prosthesis (BS 0.2%/patient year: CE 1.2%/patient year, P less than0.02).(ABSTRACT TRUNCATED AT 250 WORDS)