Hemodynamic and volume changes associated with captopril.

Abstract

The effects of captopril on bemodynamic, rolmne, and neurohumoral indices were inrestigated in 33 patients with essential hypertension or renal arterial disease. Changes associated with treatment were studied under two conditions: immediately (V4 to 1 boar) after administration of the drug, or after 5 to 7 days of therapy. Blood pressure (BP) reduction in both conditions was due to a reduction in total peripheral resistance (TPR) (r = 0.714, p < 0.001 for A MAP / TPR); there was no significant change in either cardiac output or heart rate. The immediate BP and TPR responses were significantly related to pretreatment plasma renin activity (PRA) (r = 0.737, p < 0.001), but this correlation was much weaker (r -0392, p > 0.50) after maintained treatment. Response to therapy could not be predicted from either bemodynamic or volume characteristics of the patients (r -0.265, NS for A MAP / TBV and -0.262, NS for A MAP / cardiac output).