A hemodynamic study of arteriolar changes in patients with previous malignant hypertension

Blood flow resistance was studied in two peripheral vascular beds in 15 patients with previous malignant hypertension and in matched groups of patients with "benign" hypertension and control subjects. Both hypertensive groups had significantly higher resistance in the hands (skin vessel bed) at maximal dilatation (2.5 and 2.5 U, respectively) than the normotensive group (1.9 U) (p less than 0.01). This increase indicates structural changes in the arteriolar wall in both hypertensive groups. It indicates a similar degree of adaptation of the vascular changes to the present blood pressure level in both hypertensive groups, although the initial blood pressure had been much higher in the group with previous malignant hypertension than in the group with "benign" hypertension. Different findings were made in the calves (muscle vessel bed), and the most severe changes were found in patients with previous malignant hypertension. Resistance at maximal dilatation was 2.4 U compared to 1.9 U in the group with "benign" hypertension (p less than 0.05) and 1.6 U in the control group (p less than 0.001 and p less than 0.05, respectively).