Reproducibility and correlations of right ventricular end-diastolic volume index measured by real-time three-dimensional echocardiography.

BACKGROUND: To correlate right ventricular volumes measured by real-time three-dimensional echocardiography (RT3DE) with left ventricular volume indices in patients with or without left-sided heart diseases.

METHODS: For this retrospective, we reviewed 806 consecutive RT3DE examinations with quantitative evaluation of both the left and the right (RV) ventricle. We excluded cases of disease or surgery that would directly affect the size of the RV (eg, intracardiac shunt, significant tricuspid, or pulmonic regurgitation) as well as poor sonographic image quality, leaving a total of 701 studies for analysis. RV volumetric quantification was performed using dedicated software.

RESULTS: Linear regression analysis showed that left ventricular stroke volume index significantly correlated with RV end-diastolic volume index (RVEDVI) (r = 0.78, p < 0.0001). Overall, 4% (28 of 701) of the patients had RVEDVI lower than 50 ml/m(2) , and 12% (84 of 701) had RVEDVI greater than 100 ml/m(2) . Intraclass correlation coefficient ranged from 0.91 to 0.99 for intraobserver and 0.85 to 0.98 for interobserver reproducibility.

CONCLUSIONS: RT3DE was feasible and reproducible for quantifying RV volume. In patients without known primary RV pathology, RV volume strongly correlated with left ventricular stroke volume.