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Choice of replacement valve in the elderly.

BACKGROUND AND AIMS OF THE STUDY
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.