Abstract
Long-term Results of Valve Replacement with Bioprosthesis: Evalution of Prosthetic Valve Function by Echography. Between May, 1988 and June, 1991, bioprosthetic valves in the mitral position were valuted echocardiograohically in 30 patiants. Of the 30 patiants, 15 (replacement group)underwent replacement of the bioprosthesis in this period, because of primary tissue failure of the bioprosthesis. The other 15 patiants (nonsurgical group) have not required replacement of the bioprosthesis. There were no significiant differences in left ventliculer dimention, and mitral valve area on the echocardio-gram between non-surgical group and re-opera-ted group. However, peak-flow veloci-ty through the bioprosthesis was significantly high in the replacement group than non-surgical group, and the peak-flow velocity in the 15 of the replacement group was more than 1.95m/sec. We conclude that echocardiography, especially Doppler echocardiography is an effective and reliable method to determine the timing of replacement of bioprosthesis with primary tissue failure.
