Assessment of stroke volume and cardiac output by Doppler echocardiography.

The authors used the pulse and continuous-wave Doppler technique to perform 51 measurements of stroke volume and cardiac output in 37 persons. Results were compared with those obtained using Fick's principle of thermodilution (immediately subsequent or simultaneous). Regression analysis showed a close correlation between Doppler and haemodynamic values - r = 0.86 for stroke volume and 0.94 for cardiac output (p less than 0.001). Using the paired t-test, the methods did not differ significantly. Standard deviation of Doppler stroke volume values from reference haemodynamic values was 10%, and only two measurements differed by more than 25%. Doppler determination of cardiac output can be therefore recommended as an alternative method in patients with high-quality echo Doppler recordings.