[Change in hemodynamic indices in progressive hypertension]

The results of a long-term observation (for 1 to 4 1/2 years) of haemodynamic changes in 32 non-treated patients with stage II essential hypertension are presented. In 18 patients the lesion did not progress throughout the observation period (group I). At re-examination the haemodynamic parameters in this group of patients did not change significantly, although in some of them the haemodynamic mechanism of maintenance of hypertension underwent certain changes: the cardiac output decreased and the total peripheral resistance increased. In 14 patients (Group 2) their essential hypertension was progressively developing. At the same time a deceleration of the heart contractions rate, a reduction of the cardiac and stroke outputs, a decrease of the circulating blood volume, and an increase of the total peripheral resistance were noted. The reduction of the cardiac output was directly proportional to its initial value (r = +0.78, P less than 0.01) and to the elevation of the arterial pressure (r = +0.71, P less than 0.01). The most distinct changes were noted in 3 patients who developed signs of cardiac insufficiency during the period between the two examinations. The possible mechanisms of haemodynamic changes under the progression of essential hypertension are discussed.