Normal Values of Three-Dimensional Right Ventricular Size and Function Measurements: Results of the World Alliance Societies of Echocardiography Study

Abstract

Normal values for 3D right ventricular (RV) size and function are not well established, as they originate from small studies that involved predominantly white North American and European populations, did not use RV-focused views and relied on older 3D RV analysis software . The World Alliance of Societies of Echocardiography (WASE) study was designed to generate reference ranges for normal subjects around the world. In this study, we sought to assess the world-wide capability of 3D imaging of the right ventricle and report size and function measurements, including their dependency on age, sex and ethnicity. Healthy subjects free of cardiac, pulmonary and renal disease were prospectively enrolled at 19 centers in 15 countries, including 6 continents. 3D wide-angle RV datasets were obtained and analyzed using dedicated RV software (Tomtec) to measure end-diastolic and end-systolic volumes (EDV, ESV), stroke volume (SV) and ejection fraction (EF). Results were categorized by sex, age (18-40, 41-65 and >65 years) and ethnicity. Of the 2007 subjects with attempted 3D RV acquisitions, 1051 had adequate image quality for confident measurements. Upper and lower limits for BSA-indexed EDV (mL/m2) and ESV (mL/m2) and EF (%) were [48, 95], [19, 43] and [44, 58] for men and [42, 81], [16, 36] and [46, 61] for women. Men had significantly larger EDV, ESV and SV (even after BSA indexing) and lower EF than women (p<0.05). EDV and ESV did not show any meaningful differences between age groups. 3D RV volumes were smallest in Asians. Reliability of 3D RV acquisition is low worldwide underscoring the importance for future improvements in imaging techniques. Sex and race must be taken into consideration in the assessment of both RV volumes and EF.