title: Prophylactic reoperation for strut fractures of the Björk-Shiley convexo-concave heart valve.
abstract: Outlet strut fracture of the Björk-Shiley Convexo-Concave (C/C) heart valve is the current paradigm of structural failure of mechanical heart valve prostheses. The estimated risk of fracture for C/C valves varies from 0.02% to 2.5% per patient-year, depending on valve size, opening angle, date of manufacture and position as a mitral or aortic replacement. This report examines our experience with 396 implants, comprising 346 C/C 60 degrees valves and 50 C/C 70 degrees valves. The 30-day mortality was 1.8%. Through April 1993, mean follow up was 8.9 years, incorporating 2971 patient-years and knowledge of the current status of 91.5% (356/389) of operative survivors. Late mortality was 3.7% per patient-year, including one 60 degrees and one 70 degrees outlet strut fracture. To evaluate the risk of semi-elective valve re-replacement at our institution, we reviewed the results of isolated re-replacements of failing or incipiently failing bioprostheses in 65 patients who had no serious co-morbidity and who were NYHA Class III or lower immediately before the procedure. The 30-day mortality was 4.6% and the overall serious morbidity rate was 10.8%, necessitating six repeat reoperations. When these factors were balanced against the life expectancy and general status of five patients with large-size, higher-fracture-risk 70 degrees C/C valves, it was concluded that only two patients remained possible reoperation candidates. Consideration for re-replacement of a normally functioning C/C heart valve should take into account institution-specific experience because structural failure remains a low risk compared to valve-related complications engendered by reoperation.
authors.affiliation: Thoracic and Cardiovascular Surgery, Klinikum RWTH Aachen, Germany.
authors.forename: F A
authors.initials: FA
authors.lastname: Schöndube
authors.forename: W
authors.initials: W
authors.lastname: Althoff
authors.forename: H C
authors.initials: HC
authors.lastname: Dörge
authors.forename: M
authors.initials: M
authors.lastname: Voss
authors.forename: J L
authors.initials: JL
authors.lastname: Laufer
authors.forename: J G
authors.initials: JG
authors.lastname: Chandler
authors.forename: B J
authors.initials: BJ
authors.lastname: Messmer
mesh_terms: D000328:Adult; D000368:Aged; D001021:Aortic Valve; D001705:Bioprosthesis; D005260:Female; D006350:Heart Valve Prosthesis / Q000401:mortality; D006801:Humans; D008297:Male; D008875:Middle Aged; D008943:Mitral Valve; D011475:Prosthesis Failure; D012086:Reoperation; D012189:Retrospective Studies; D015996:Survival Rate