THE EFFECTS OF 1-HYDRAZINOPHTHALAZINE UPON CORONARY HEMODYNAMICS AND MYOCARDIAL OXYGEN METABOLISM IN ESSENTIAL HYPERTENSION 1

Abstract

Cardiac and coronary hemodynamics and 02 metabolism were studied before and after intravenous administration of 1-hydrazinophthalazine to 6 hypertensive patients and in 5 patients using saline solution instead of Hydralazine. The drug produced an increase in heart rate, a fall in systemic arterial blood pressure and peripheral arterial resistance, a decreased arterial and mixed venous CO2 content, and a smaller arteriovenous CO2 difference. The change in cardiac index was variable but there was a slight increase in the over-all average. In the coronary circulation significant changes were an increased coronary blood flow, diminished coronary vascular resistance, and decreased arterial-coronary sinus O2 difference. Myocardial O2 consumption was not changed.