In assessing paravalvular regurgitation in mitral prostheses, the actual area of dehiscence can be detected by TEE as an area of echo drop-out outside the sewing ring (Figure 20 A). This must be confirmed by the presence of the paravalvular regurgitant jet on color flow imaging. In order to facilitate communication between the echocardiographer and the interventionalist, the location of the dehiscence is best described in relation to internal landmarks such as the left atrial appendage, aortic valve and crux of the heart (Figure 21).

The entire sewing ring should be examined by meticulously sweeping the mitral prosthesis from 0 to 180°, quantitating the circumferential extent of dehiscence by noting the angle at which the jet(s) is(are) first detected to the point of disappearance. Multiple regurgitant jets can be identified by the presence of intervening areas where the attachment of the sewing ring is intact.

Real-time 3D TEE imaging is a major advance in the localization and quantification of paravalvular mitral regurgitation, because it can consistently provide an en face view of the mitral prosthesis allowing the accurate determination of the number and location(s) of areas of paravalvular dehiscence (Figure 22A). The location and orientation of the paravalvular regurgitant jets can be further delineated using 3D color flow imaging (Figure 23).

In paravalvular aortic regurgitation addition to mid-esophageal long and short axis views (Figure 24 A, B), the transgastric view should be attempted and a good display of the left ventricular outflow tract can be obtained by using a longitudinal imaging plane at about 100 to 120° with leftward flexion of the transducer (Figure 24 C). A zero degree deep transgastric view with anteflexion and leftward angulation may also be helpful (Figure 24D).