Comparison Between Four-Chamber and Right Ventricular–Focused Views for the Quantitative Evaluation of Right Ventricular Size and Function

BACKGROUND: Right ventricular (RV) function plays a pivotal prognostic role in multiple cardiac diseases. Echocardiography guidelines recommend that RV quantification be performed in the RV-focused view, which is theoretically more reproducible than the four-chamber (4Ch) view. However, differences between views in RV size and function measurements have never been systematically studied. Accordingly, the aim of this study was to compare (1) RV size and function parameters obtained from the RV-focused and 4Ch views and (2) test-retest variability between these two views. METHODS: Fifty patients (26 men; mean age, 63 ± 18 years) undergoing clinically indicated transthoracic echocardiography were prospectively enrolled. Each patient underwent three repeated acquisitions of the 4Ch and RV-focused views by two sonographers. The first operator performed two acquisitions at the beginning and the end of the clinical transthoracic echocardiographic study, and the second operator performed the third acquisition afterward. RV size and function measurements were obtained from the two views and compared using paired t-test analysis and Bland-Altman analysis. Intra- and interoperator test-retest and intra- and interreader variability for both views were assessed using intraclass correlations and coefficients of variation. RESULTS: All RV size parameters were significantly larger when measured in the RV-focused view compared with the 4Ch view. Also, all RV function parameters, including RV free wall and global longitudinal strain, were larger in magnitude when measured in the RV-focused view. Measurements variability was consistently better for the RV-focused view. CONCLUSIONS: RV size and function measurements obtained from the RV-focused and 4Ch views are not interchangeable. RV size and function parameters measured from the RV-focused view are more reproducible than from 4Ch acquisitions. Therefore, only the RV-focused view should be used for quantitative assessment of the right ventricle.