Doppler flowmetry in the lower thoracic aorta. An indirect estimation of cardiac output.
Duplex scanning of the lower thoracic aorta was performed on 67 patients subjected to routine left and right heart catheterization with estimation of cardiac output ad modum Fick. Adequate Doppler signals from the lower thoracic aorta were obtained in 59 patients (88%), 26 of whom had aortic valve abnormality. A high correlation was found between the Doppler and Fick findings (r=0.89), with a regression line intercepting close to zero (cardiac output = 1.76 X Doppler flow +0.05). The presence of aortic valve abnormality did not seem to influence the accuracy of the Doppler flow results. It is concluded that Doppler flowmetry in the lower thoracic aorta is a useful method in estimation of resting cardiac output, especially in patients with aortic valve lesions making Doppler flowmetry in the ascending aorta impossible.
D000328:Adult; D000368:Aged; D001013:Aorta, Thoracic / Q000503:physiopathology*; D001783:Blood Flow Velocity; D002302:Cardiac Output; D003327:Coronary Disease / Q000175:diagnosis* / Q000503:physiopathology; D005260:Female; D006349:Heart Valve Diseases / Q000175:diagnosis / Q000503:physiopathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D014463:Ultrasonography