Comprehensive Evaluation of Tricuspid Regurgitation Location and Severity Using Vena Contracta Analysis: A Color Doppler Three-Dimensional Transesophageal Echocardiographic Study

Background: The clinical significance of three-dimensional (3D) vena contracta area (VCA) in tricuspid regurgitation (TR) is not fully elucidated. The aim of this study was to investigate the diagnostic accuracy of 3D VCA using 3D echocardiography-derived regurgitation volume as a reference standard. Methods: One hundred sixteen patients with at least moderate TR underwent two-dimensional transthoracic and color Doppler 3D transesophageal echocardiography. The 3D vena contracta, which was located at the narrowest neck of the TR jet just above and toward the right atrial side of the flow convergence zone, was assessed for TR location and severity. Results: As for TR location, patients with severe functional TR had the highest prevalence of central jet location among TR subgroups, whereas patients with severe primary TR showed a greater spatial extent of TR jet location involved compared with the moderate TR group (P<.05 for both). As for TR severity, a 3D VCA cutoff value of 0.61 cm(2) discriminated severe TR with sensitivity of 78% and specificity of 97% in the total patient population (area under the curve=0.93, P<.001). Multivariate analysis revealed that 3D VCA, a dilated right ventricle, and hepatic vein systolic reversal were independently associated with regurgitant volume (P<.001 for all). The chi(2) value for the model that incorporated clinical and two-dimensional integrative parameters and 3D VCA > 0.61 cm(2) to evaluate severe TR was significantly higher than that for the model that incorporated only clinical and two-dimensional integrative parameters (P=.001). Conclusions: Three-dimensional VCA has independent and incremental diagnostic value for evaluating severe TR. Comprehensive evaluation of TR location and severity using 3D vena contracta analysis may help in treatment selection for TR.