Right Ventricular Analysis Using Real-time Three-dimensional Echocardiography for Preload Dependency

BACKGROUND: The importance of the right ventricle (RV) has been increasingly recognized, and accurate RV measurement has become necessary. However, assessment of the RV with two-dimensional (2D) echocardiography has several limitations. As the development of novel methods for RV measurement continues, we can expect more accordant values related to RV geometry. METHODS: Fifty-eight subjects who were examined by transthoracic echocardiography (TTE) immediately before and after hemodialysis (HD) were enrolled. Real-time, full-volume, three-dimensional (3D) echocardiographic images were acquired and analyzed using dedicated software. Conventional RV parameters for RV size and function were measured for comparison with pre-HD and post-HD values by both 2D-TTE and 3D-TTE. RESULTS: 3D RV volumes and ejection fractions were significantly decreased after HD. The values of the 3D image-derived RV dimensions, tricuspid annular plane systolic excursion (TAPSE), fractional area change (FAC), and longitudinal strain were also affected by acute preload changes (TAPSE pre-HD: 22.4 ± 4.0 mm, post-HD: 19.0 ± 4.2 mm, p < 0.001; FAC pre-HD: 49.6% ± 5.9%, post-HD: 46.4% ± 5.5%, p < 0.001; septal longitudinal strain pre-HD: -20.1% ± 3.7%, post-HD: -16.8% ± 3.8%, p < 0.001). With the exception of FAC, most 2D RV parameters were well correlated with the 3D values. CONCLUSIONS: Various parameters representing RV anatomy and function were acquired easily and more accurately from 3D echocardiographic images than from 2D images but were affected by acute preload changes. 3D TTE could be a new modality for assessing RV function and size, but each value from 3D TTE should be interpreted with caution while considering the loading condition of the patients.