[Time-related degeneration of Carpentier-Edwards bioprosthesis in mitral position]

Carpentier-Edwards bioprostheses have been shown to provide a low incidence of valve-related complications, especially thromboembolism, but the durability has caused the serious concern. This report suggests that Carpentier-Edwards prostheses have been gradually degenerative, and stenotic degeneration and the year after operation are well correlative. In Osaka National Hospital, Carpentier-Edwards prostheses were implanted in 89 patients in mitral position from 1973 to 1981. Of all the patients, 50 patients were undertaken to single valve replacement in mitral position and could be followed up in our department. For a total of 50 patients, materials are 30 patients who could be detected by clinical findings, pulsed Doppler echocardiography, cardiac catheterization and soft X-ray evaluation in explanted prostheses at reoperation. Follow-up duration was ranged 4.2 to 12.1 years with a mean duration of 7.94 years. The age ranged from 32 to 71 years of age. The initial diagnosis of the time-related degeneration was the appearance of newly acoustic rumbiling murmur. Furthermore, regurgitant murmur, arrythmia (atrial fibrillation) and cardiac enlargement were followed in addition to rumbling murmur. The assess of the transmitral flow such as pressure half time and peak pressure gradient by pulsed Doppler echocardiography was the easy way to evaluated the time-related degeneration. Time-related stenotic change by pulsed Doppler was expressed as a linearized curve. At 6 years and below valve function seemed not to be impaired but stenotic dominant degeneration with the cusp tear was prominent beyond 7 years. Cardiac catheterization data could make sure of the pulsed Doppler findings by assessing mitral valve gradient and mitral valve area.(ABSTRACT TRUNCATED AT 250 WORDS)