Short-term Therapy of Severe Hypertension. Hemodynamic Correlates of the Antihypertensive Response in Man

Ten severely hypertensive patients were randomized into five treatment groups: vasodilators; vasodilators plus diuretics; sympatholytics; sympatholytics plus diuretics; and sympatholytics, diuretics, and vasodialtors. Cardiac index was measured daily by echocardiography, and total peripheral resistance (TPR) calculated. Plasma renin activity (PRA) and creatinine clearance (CCR) were measured every other day. There was no difference in antihypertensive response. Seven patients, whose initial TPR was high, responded to treatment with a fall in TPR, regardless of regimen. Three patients with a high pretreatment cardiac index responded with a fall in cardiac index. Changes in TPR or cardiac index were not related to changes in CCR. There was no correlation between PRA and either blood pressure or TPR. It is concluded that the pretreatment hemodynamic status of severely hypertensive patients is the major determinant of the hemodynamic response to antihypertensive therapy.