[Non-invasive measurement by Doppler pulse of cardiac output and maximal aortic acceleration in essential arterial hypertension].

Three groups of 11 male subjects with the same mean age were studied: normotensives (group I), patients with sustained essential hypertension (group II) and patients with borderline hypertension (group III). M-mode echocardiography provided a measure of aortic root systolic diameter (D) and left ventricular mass index (LVMi, g/m2). We have used a 4 MHz pulsed doppler velocity meter with spectral analysis to measure instantaneous ascending aortic blood velocity. Measurements values were averaged during 10 s and included: stroke volume (SV, cm3 = integrated velocity over one cardiac cycle.aortic cross sectional area (3.14D2/4)), cardiac output (CO, cm3 = SV.heart rate), systemic vascular resistance (SVR, mmHg/cm3.s-1 = MAP/co) and maximal aortic acceleration (MA, cm/s2). (Table: see text). Stroke volume and cardiac output were similar in three groups. SVR was higher in group II than in group I. The myocardial contractility appreciated from the maximal aortic acceleration (Bennett et al, Cardiovasc Res 1984; 18: 632-8) was increased in patients with borderline hypertension and remained within the normal range in patients with sustained essential hypertension despite and increase in cardiac mass.