Measurement of Stroke Volume With Echocardiography Compared to Gold Standard Cardiac Magnetic Resonance Imaging: An Observational Study.

OBJECTIVES:The authors aimed to compare the assessment of left ventricular (LV) stroke volume with transthoracic echocardiography (TTE) using 2- and 3-dimensional (2D and 3D) Doppler and volumetric techniques with gold standard cardiac magnetic resonance imaging (CMR). DESIGN:An observational study. SETTING:A medical research institute. PARTICIPANTS:A total of 187 volunteer participants free of known structural heart disease. INTERVENTIONS:None. MEASUREMENTS AND MAIN RESULTS:LV stroke volume was measured with TTE using the following 4 techniques: LV outflow tract (LVOT) pulsed wave Doppler with 2D LVOT area, LVOT pulsed wave Doppler with 3D LVOT area, 2D volumetric (Simpson's biplane), and 3D volumetric techniques. This was compared with gold standard CMR. Stroke volume measured with echocardiography underestimated stroke volume compared to CMR by all techniques (p < 0.001 for all values compared to CMR). The LVOT Doppler stroke volume with a 3D area most closely agreed with CMR, with a bias of 6.35%. This bias progressively increased with 3D volumetric (13.4%), LVOT Doppler with a 2D area (15.1%), and 2D volumetric (18.3%) stroke volume techniques, with wider limits of agreement. CONCLUSION:Of the 4 echocardiographic LV stroke volume measurement methods the authors assessed, stroke volume with LVOT Doppler using 3D measurement of LVOT area most closely approximates gold standard CMR.