From Jaunary 1985 to December 1992, of 1257 patients who underwwent a heart valve replacement 210(16.8%) underwent reoperation on prosthetic heart valves, and 6 of them had a second valve reoperation.
The indications for reoperation were structural deterioration (176 cases, 81.5%), prosthetic valve endocarditis (25 cases, 11.6%), paravalvular leak (12 cases, 5.6%), valve thrombosis (2 cases, 0.9%) and ascending aortic aneurysm (1 case, 0.4%).
Prosthetic valve failure developed most frequently in mitral position (57.9%) and prosthetic valve endocarditis and paravalvular leak developed significantly in the aortic valve (40%, 75%) (P<0.02).
Mean intervals between the primary valve operation were 105.3*28.4 months in the case of prosthetic valve failure, 61.5*38.5 months in proshtetic valve endocarditis, 26.8*31.2 months in paravalvualr leak, and 25.0*7.0 months in valve thrombosis.
In bioprostheses, the intervals were in 102.0*23.9 months in the aortic valve, and 103.6*30.8 months in the mitral valve.
The overall hospital mortality rate was 7.9% (17/26):15% in aortic valve reoperation (6/40), 6.5% in reoperation on the mitral prostheses (9/135) and 5.7% in lnultiple valve replacement (2.35). Low cardaic output syndrome was the most common
cause
of
death (70.6%). Advanced New York Heart Association class (P=0.00298). explant period (P=0.0031), aortic cross-clamp time (P=0.0070), prosthetic valve endocarditis (P=0.0101), paravalvularr leak (P=0.0096), and second reoperation (P=0.00036) were
the
independent risk factors, but age, sex, valve position and multiple valve replacement did not have any influence on operative mortality.
Mean follow up period was 38.6*24.5 months and total patient follow up period was 633.3 patient year. Actuarial survival at 8 year was 97.3*3.0% and 5 year event-free survival was 80.0*13.7%.
The surgical risk of reoperation on heart valve prostheses in the advanced NYHA class patients is higher, so reoperation before severe hemodynamic impairment occurs is recommended.
(Korean J Thoracic Cardiovas Surg 1995;28:23-30)
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