title: Choice of replacement valve in the elderly.
abstract: OBJECTIVE
  Little comparative information exists on the outcome of the valve replacement with bioprostheses or mechanical valves in the elderly. This study was carried out to make such a comparison.
  
  
  METHODS
  Follow up data were examined from 219 patients aged > or = 65 years who underwent aortic and/or mitral valve replacement using bioprosthetic (n = 67) or mechanical valve (n = 152) between April 1979 and December 1993. The mean follow up periods were 6.3 +/- 2.8 years after bioprosthesis and 4.9 +/- 2.1 years after mechanical valve implantation.
  
  
  RESULTS
  Although the actuarial rate of structural deterioration was higher in patients with bioprosthetic valves than in those with mechanical valves (58% versus 100% freedom at 10 years after surgery, p < 0.01), no such prosthesis-related difference was seen in the subgroup of patients aged > or = 70 (100% versus 100% at nine years, p = N.S.). The actuarial rate of major bleeding was higher after mechanical valve implantation than after bioprosthetic valve placement (90% versus 100% freedom at 10 years, p < 0.05); this lower rate with bioprosthetic valves was maintained in patients aged > or = 70 (78% versus 100% at nine years, p < 0.05). There were no significant differences in the incidences of thromboembolism and bacterial endocarditis between the two valve types.
  
  
  CONCLUSIONS
  Structural degeneration of bioprosthetic devices was a major problem in patients aged 65-70 years, but it was essentially negligible in those aged > or = 70 years. Anticoagulant-related bleeding was a major problem with mechanical valves in both age groups. Therefore, for patients older than 70 years, valve replacement with a bioprosthesis appears to be the method of choice.
authors.affiliation: Department of Internal Medicine, National Cardiovascular Center, Osaka, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Kobayashi
authors.forename: K
authors.initials: K
authors.lastname: Eishi
authors.forename: S
authors.initials: S
authors.lastname: Nagata
authors.forename: K
authors.initials: K
authors.lastname: Nakano
authors.forename: Y
authors.initials: Y
authors.lastname: Sasako
authors.forename: J
authors.initials: J
authors.lastname: Kobayashi
authors.forename: Y
authors.initials: Y
authors.lastname: Kosakai
authors.forename: K
authors.initials: K
authors.lastname: Miyatake
mesh_terms: D000367:Age Factors; D000368:Aged; D001021:Aortic Valve / Q000601:surgery*; D001705:Bioprosthesis; D016009:Chi-Square Distribution; D005069:Evaluation Studies as Topic; D005260:Female; D005500:Follow-Up Studies; D006349:Heart Valve Diseases / Q000503:physiopathology / Q000601:surgery; D006350:Heart Valve Prosthesis / Q000295:instrumentation*; D006801:Humans; D008297:Male; D008943:Mitral Valve / Q000601:surgery*; D011183:Postoperative Complications / Q000401:mortality*; D011379:Prognosis; D011474:Prosthesis Design; D012086:Reoperation; D015996:Survival Rate