Two- and three-dimensional transthoracic echocardiographic assessment of superior vena cava, crista terminalis, and right atrial appendage using the right parasternal approach

BackgroundThe noninvasive assessment of superior vena cava (SVC), crista terminalis (CT), and the right atrial appendage (RAA) has clinical implications in determining the right atrium (RA) pressure in adult patients in whom the inferior vena cava cannot be imaged, in planning electrophysiological procedures and for evaluation of thrombi in RA/RAA. It is difficult to image these structures using standard two-dimensional transthoracic echocardiography (2DTTE), but the right parasternal approach has shown promise in the very few studies published so far. AimThe aim of this study was to show the feasibility of this approach and its usefulness in qualitative and quantitative assessments of these structures by both 2D and three (3D) TTE in patients with and without known cardiac pathologies. Material and MethodsThe study consisted of 38 adult patients, 17 of whom had cardiac pathologies (Group 1) while the remainder (Group 2) had no evidence of heart disease clinically or by echocardiography. Results and ConclusionBoth SVC and RAA could be imaged by 2DTTE and 3DTTE in 53% of 40 patients (two separate groups of 20 consecutive patients) studied demonstrating the technical feasibility of this approach. SVC size and collapsibility, CT and RAA size, and RAA fractional shortening were evaluated in both groups by both 2D and 3DTTE. 3DTTE provided incremental value over 2DTTE by its ability to view en face the SVC in short axis and the base of RAA and RAA volumes resulting in more comprehensive assessment of their size and function.