Cineradiographic evaluation of ATS open pivot bileaflet valves

Echocardiography and cineradiography are both valuable for the evaluation of prosthetic valve function, especially of mechanical valves. Although Doppler echocardiography data are available for the recently developed ATS valve, cineradiographic evaluation of leaflet movement of the valve has not been performed.

Five patients received aortic and another five mitral valve replacement with the open pivot ATS bileaflet prosthetic valve. There were three men and seven women; mean patient age was 58.8 years. Cineradiographic and Doppler echocardiographic evaluations of the ATS valve were performed early after surgery in all 10 patients.

There were no early deaths after surgery or after discharge from the hospital. No valve-related complications were seen, and no clinical symptoms or signs of prosthetic malfunction were observed during the follow up period. Doppler-derived values of the ATS valve were comparable with those previously reported; however, cineradiography of the valve demonstrated that the mean angle enclosed by the two open leaflets was 37.6 degrees (range: 34 degrees to 44 degrees) in the aortic position and 29.7 degrees (range: 20 degrees to 35 degrees) in the mitral position. Mean leaflet mobility was 93.0 degrees (range: 86 degrees to 96 degrees) in the aortic position and 100.0 degrees (range: 92 degrees to 110 degrees) in the mitral position. Thus, the opening of the normally functioning ATS valves in vivo was less than that observed in vitro and reported by the manufacturer.

These results suggest that unevenly distributed blood flows with different velocities through the two side orifices and the central orifice may result in incomplete opening of the ATS leaflets, which respond with great sensitivity to localized blood flow. Our findings appear to be important to avoid the removal of a normally functioning ATS valve only because the leaflet opening appears to be 'restricted'.