Background:
The coaptation length (CL) of the mitral valve leaflet decreases with increasing mitral regurgitation. Visualization of the CL of the tricuspid valve (TV) is challenging using conventional 2D echocardiography. The aims of this study were: (1) to test the feasibility of visualizing and quantifying the CL of the TV using three-dimensional (3D) transesophageal echocardiography (TEE), and (2) to study it relationship with the severity of tricuspid regurgitation (TR).
Methods:
Full-volume 3D TEE datasets of the TV were obtained in 24 patients from the transgastric approach. Using multiplanar reconstruction, short-axis plane depicting an en-face view of the TV was used to mark the central coaptation point (Fig. A). Three planes cutting through this point were then selected to view the 3 coaptation lines between: (1) anterior and posterior, (2) septal and anterior, and (3) septal and posterior TV leaflets (Figs. B-D). The CL was measured in each of these planes to obtain mean CL. The severity of tricuspid regurgitation was graded qualitatively as “none”, “trace”, “mild” and “moderate”.
Results:
Visualization of leaflet coaptation was feasible in 17/24 patients (71%). The mean CL was 0.89±0.03 cm in patients with no TR (N=4), 0.64±0.13 with trace TR (N=6), 0.50±0.07 with mild TR (N=3) and 0.13±0.11 with moderate TR (N=4). Since there was no overlap between the “moderate” group and the other 3 groups, the threshold of average CL for moderate TR was estimated to be between 0.25 (highest value in the “moderate” group) and 0.39 cm (lowest value in the other groups) (Fig. E).
Conclusion:
Visualization of the TV leaflet coaptation length from transgastric 3D TEE images is feasible in the majority of patients. TV coaptation length is inversely related to the severity of TR. The ability to visualize and quantify the CL of the TV may be useful when planning tricuspid valve repair surgery. Our findings suggest that CL below the threshold may indicate clinically significant TR.
Three-dimensional transesophageal echocardiography incremental value in a case with a rare combination of tricuspid valve prolapse and rheumatic mitral valve stenosis