Reference values for right ventricular geometry and function by three-dimensional echocardiography. A multicenter study of a large cohort of healthy subjects

Background: Right ventricular (RV) size and function are important predictors of outcome in heart and lung diseases. 3DE is the only echo modality allowing the assessment of RV volumes and function. However, population-based reference values obtained from a large cohort of healthy subjects are still lacking, hindering the adoption of 3DE into routine clinical practice. Methods: 533 healthy subjects (51% females, 44 + /-16 years, range 13-90) were prospectively recruited at 3 Institutions (C1, C2 and C3). Enrolled subjects underwent a complete 2D, Doppler and 3D transthoracic examination. Interinstitutional agreement of RV volume measurements (4D RV function, TomTec Imaging Systems, D) was tested in a sample of 30 randomly chosen 3D data sets. Results: Bland-Altman analysis of intercenter reproducibility showed a fairly good agreement for the measurements of both RV end-diastolic (EDV) (C1 vs C2: bias= 29ml, LOA 241, + 23 ml; C2 vs C3: bias= + 6 ml, LOA -27, + 39 ml; C1 vs C3: bias = 23 ml, LOA -18, + 12 ml) and end-systolic volume (ESV) (C1 vs C2: bias = 23ml, LOA -16, + 10 ml; C2 vs C3: bias= 22ml, LOA -19, + 15 ml; C1 vs C3: bias= 25ml, LOA 218, + 8ml). At multivariable regression analysis (including age, gender, body surface area -BSA, systolic and diastolic blood pressure, and heart rate), only age and BSA were identified as independent predictors of RV EDV (R2=0.38) and ESV (R2=0.35). Reference values for RV geometry and function are summarized in Table. Conclusions: These reference values obtained in a large cohort of healthy subjects should encourage the routine assessment of RV volumes and ejection fraction in clinical practice and their inclusion in the echocardiographic report. Our results also show significant age-related changes in RV geometry and function that should be taken into account when assessing RV remodelling in cardiopulmonary diseases