Misleading image of mechanical valve leaflet by transesophageal echocardiography.

Although bileaflet prosthetic valve function is commonly assessed by means of transesophageal echocardiography (TEE) during surgery, the author reports that the leaflet image is not a real image but an artifact. As the depth of the transducer is altered, the leaflet image is gradually skewed in relation to the plane of the prosthetic valve ring. The leaflet-like image consistently overlaps the line that is drawn from the transducer position to the atrial side edge of the leaflet, indicating that this image is caused by reverberations. Three-dimensional TEE shows that the leaflet image is not semilunar but is elongated towards the left ventricle and unusually tilted. As viewed from the ventricular side, the ring image is elongated and forms a cylinder-like image in the left ventricle, and the leaflets appear to be opening and closing at the bottom of this cylinder. Therefore, TEE assessment of leaflets in the open position can be misleading.