Strut fracture and other events after valve replacement with the 60 degree convexoconcave Björk-Shiley prosthesis.
A total of 688 patients received 808 Björk-Shiley prostheses during a 5 year span. Cumulative duration of follow-up totaled 1175.4 patient-years (1368 valve-years). Linearized rates in percent per patient-year for valve-related events (95% confidence limits) were: strut fracture, 0.5 (0.00 to 1.03); infective endocarditis, 0.94 (0.39 to 1.49); thromboembolism, 2.2 (1.37 to 3.052); valve impingement, 0.3 (0.00 to 0.77); and anticoagulant-related hemorrhage, 3.1 (2.15 to 4.14). No valve thrombosis occurred. Actuarial patient survival, including in-hospital mortality, was: aortic valve replacement, 79.8 +/- 3.4%; mitral valve replacement, 71.7 +/- 4.9%; double valve replacement, 59.8 +/- 7.5%. Incremental risk factors for death were age over 65 (p = .001), preoperative infective endocarditis (p = .04), and associated procedures (p = .0002). Although this prosthesis carries a low risk of infective endocarditis and thromboembolism, concern has been raised regarding its structural integrity.
D000206:Actuarial Analysis; D001021:Aortic Valve; D004697:Endocarditis, Bacterial / Q000453:epidemiology; D005260:Female; D005500:Follow-Up Studies; D006349:Heart Valve Diseases / Q000601:surgery*; D006350:Heart Valve Prosthesis; D006470:Hemorrhage / Q000453:epidemiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D008943:Mitral Valve; D011183:Postoperative Complications / Q000453:epidemiology*; D011474:Prosthesis Design; D011475:Prosthesis Failure; D012306:Risk; D013923:Thromboembolism / Q000453:epidemiology; D013997:Time Factors