Stroke volume measured by pulsed ultrasound Doppler and M-mode echocardiography.

The velocity of the bloodstream in the ascending aorta was measured by pulsed ultrasound Doppler. The diameter of the aorta was measured by M-mode echocardiography. Forty-three measurements were performed in six patients, who all had a Swan-Ganz catheter. The calculated stroke volumes from the Doppler-Echo method were compared with the stroke volumes measured by the thermodilution technique, which was performed simultaneously with the Doppler measurements. The correlation between the measurements was good (r = 0.08). It is concluded that it is possible non-invasively to measure stroke volume (and cardiac output) by means of ultrasound Doppler and an echocardiograph.