[Non-invasive measurement of cardiac output by Doppler echography]

In this review paper the theoretical and technical bases of cardiac output measurement in the thoracic extracted from the literature and obtained by the authors themselves are summarized. The main physiological assumptions required for calculations (flat velocity profile in the aorta) and the main technical options (pulsed or continuous emission of ultrasounds, spectral or simplified Doppler signal analysis, evaluation or non-evaluation of the angle of incidence by two-dimensional imaging, echographic mode of measurement of the aortic diameter) are discussed. The need for controlled studies of each equipment and method on large populations of patients is emphasized.