Acute electrocardiographic effects of captopril in the initial treatment of malignant or severe hypertension.

We evaluated electrocardiographically the acute effect of captopril in the initial treatment of malignant or severe hypertension and the findings were compared with the data obtained with diazoxide. The captopril group included seven patients treated with captopril or with a combination of diuretics. The diazoxide group included seven patients initially treated with diazoxide. A significant and similar degree of reduction in blood pressure was observed the second day after treatment in both groups. From 15 to 60 minutes after treatment, however, the reduction in mean blood pressure was more pronounced in the diazoxide group and was followed by a reflex tachycardia. In the diazoxide group, two patients went into shock and another three had nausea and vomiting, whereas in the captopril group there were no complications in any of the patients. In the captopril group ECG ST-T findings in leads V5 and V6 did not deteriorate, while in the diazoxide group there was a significant deterioration (p = 0.01). Thus captopril may be an effective and safe compound for the initial treatment of malignant or severe hypertension.