Non-invasive study of cardiac performance using Doppler ultrasound in patients with hypertension.

Using a pulsed Doppler velocimeter with spectral analysis, it is possible to measure instantaneous ascending aortic blood velocity by the suprasternal approach. Cardiac output, stroke volume and maximal acceleration are evaluated from the aortic velocity curve. Maximal aortic acceleration is increased in patients with borderline hypertension by comparison with normal subjects and patients with sustained essential hypertension of the same age. Stroke distance is calculated as the ratio between stroke volume and the cross-sectional area of aortic valve measured by echocardiography. Stroke distance is significantly decreased in patients with sustained hypertension, suggesting that the distance covered by a column of blood passing through the aortic root during one cardiac cycle is smaller in patients with hypertension than in normal subjects.