Comprehensive Assessment of Right Ventricular Function by Three-Dimensional Speckle-Tracking Echocardiography: Comparisons with Cardiac Magnetic Resonance Imaging.

Background: Three-dimensional speckle-tracking echocardiography (3D-STE) has been increasingly used to quantify right ventricular (RV) function. However, direct comparisons of 3D-STE with cardiac magnetic resonance (CMR) imaging for evaluation of RV function are limited. This study aimed to test the feasibility and accuracy of 3D-STE for the quantification of RV volumes, ejection fraction (EF), and longitudinal strain in comparison with CMR imaging and to determine whether 3D-STE for RV strain is superior to two-dimensional (2D) STE in comparison with CMR imaging.

Methods: A total of 195 consecutive patients referred for both CMR imaging and echocardiography were studied. Right ventricular end-diastolic volume (RVEDV), RV end-systolic volume (RVESV), RVEF, and 3D RV longitudinal strain (3D-RVLS) of the free wall by 3D-STE and 2D-RVLS of the free wall by 2D-STE, were compared with CMR measurements. Pearson correlation and Bland-Altman analyses were used to assess the intertechnique agreement.

Results: Right ventricular 3D-STE was feasible in 174 patients (89%). Right ventricular volumes and EF determined by 3D-STE strongly correlated with CMR values (RVEDV, r = 0.94; RVESV, r = 0.96; RVEF, r = 0.91; all P < .001). Three-dimensional STE slightly underestimated the RV volumes and longitudinal strain and overestimated the RVEF. The 3D-RVLS values correlated better than 2D-RVLS values with CMR values (0.85 vs 0.64, P < .001) with smaller bias and narrower limits of agreement (bias: 2.0 and 2.6; limits of agreement: 8.5 and 12.5, respectively). The bias and limits of agreement for 3D-STE-obtained RVLS were increased in patients with RV dilation, RVEF < 45%, or lower frame rate compared with those with normal RV size, RVEF ≥ 45%, or higher frame rate, respectively. Right ventricular 3D-STE measurements were highly reproducible.

Conclusions: The 3D-STE measurements of RV volumes, EF, and longitudinal strain are highly feasible and reproducible, and data measured by 3D-STE correlate strongly with those determined using CMR imaging. Thus, 3D-STE may be a valid alternative to CMR imaging for the quantification of RV function in everyday clinical practice.