title: Thirty-year results after implantation of the Björk-Shiley Convexo-Concave Heart valve prosthesis.
abstract: BACKGROUND
  Modifications of the Björk-Shiley valve prosthesis have shown good long-term results. The convexo-concave model, however, was recalled 27 years ago because of a propensity for breakage due to outlet strut fracture. The objective of this study is to describe the 30-year outcome after implantation of the Björk-Shiley convexo-concave mechanical heart valve prosthesis (Pfizer, Rye Brook, NY).
  
  
  METHODS
  The study included 279 patients who were operated between 1979 and 1983 at Turku University Hospital. A total of 305 valves were implanted; 205 in the aortic position and 100 in the mitral position. Patient records were reviewed for baseline characteristics and late events, data on mortality were acquired from registries.
  
  
  RESULTS
  Mean actuarial survival was 19.8 years and mean follow-up was 19.2 years (maximum 34 years). Freedom from reoperation was 91.3% at 30 years. There were 3 outlet strut fractures (2 fatal) during follow-up. Statistically significant predictors of mortality were age and concomitant coronary artery bypass grafting.
  
  
  CONCLUSIONS
  Despite the possibility of structural valve failure the Björk-Shiley convexo-concave valve confers excellent 30-year survival.
authors.affiliation: Heart Center, Turku University Hospital and University of Turku, Turku, Finland. Electronic address: jarmo.gunn@tyks.fi.
authors.forename: Jarmo M
authors.initials: JM
authors.lastname: Gunn
authors.affiliation: Heart Center, Turku University Hospital and University of Turku, Turku, Finland.
authors.forename: Markus
authors.initials: M
authors.lastname: Malmberg
authors.affiliation: Heart Center, Turku University Hospital and University of Turku, Turku, Finland.
authors.forename: Tommi
authors.initials: T
authors.lastname: Vähäsilta
authors.affiliation: Heart Center, Turku University Hospital and University of Turku, Turku, Finland.
authors.forename: Anne I
authors.initials: AI
authors.lastname: Lahti
authors.affiliation: Heart Center, Turku University Hospital and University of Turku, Turku, Finland.
authors.forename: Kari T
authors.initials: KT
authors.lastname: Kuttila
mesh_terms: D000328:Adult; D001021:Aortic Valve / Q000601:surgery*; D015331:Cohort Studies; D005260:Female; D006350:Heart Valve Prosthesis; D019918:Heart Valve Prosthesis Implantation; D006801:Humans; D008297:Male; D008875:Middle Aged; D008943:Mitral Valve / Q000601:surgery*; D011474:Prosthesis Design; D012189:Retrospective Studies; D013997:Time Factors
keywords: 35