Greiner S, et al. - In a clinical setting, researchers compared right ventricular (RV) volumetry using almost simultaneous state-of-the-art three-dimensional (3D) transthoracic echocardiography (3DE) and cardiac magnetic resonance imaging (CMR). Within 30 minutes of CMR, 47 consecutive participants had comprehensive echocardiography including 3DE. In patients with good image quality, reliable evaluation of RV-ejection fraction (-EF) can result from transthoracic 3DE, but absolute RV volumes quantified by 3DE show a systematic deviation from CMR volumetry that was neglected previously and necessitates conscientious interpretation of anatomical cardiac imaging.