Two-dimensional echocardiographic evaluation of mitral bioprosthetic function in infants and children

Two-dimensional echocardiography (2DE) was performed on 13 bioprosthetic mitral valves in 11 pediatric patients, 1 week to 46 months following implantation. Cardiac catheterization confirmed the echocardiographic findings of seven valves. The 11 normally functional bioprosthetic mitral valves by 2DE had leaflet thickness not exceeding 2.0 mm, freely moving leaflets, and normal sewing ring motion. The left atrium (LA) was enlarged only in the presence of mitral valve obstruction, atrial fibrillation, or left ventricular (LV) dysfunction. One bovine valve was stenotic due to fibrous tissue beneath normal valve leaflets; 2DE demonstrated limited leaflet motion, tissue beneath a thin valve leaflet, increase rocking motion of the sewing ring, and LA enlargement. In another patient, a bovine valve produced subaortic LV obstruction due to growth of fibrous tissue outside the stent; 2DE showed that the valve leaflets were thin and moved normally without excessive rocking of the valve ring, and identified the abnormal fibrous tissue in the LV outflow tract.