Studies of Pulmonary Hypertension. Ix. The Effects of Intravenous Hexamethonium on Pulmonary Circulation in Patients With Mitral Stenosis1

During the past five years, circulatory effects of intravenous hexamethonium have been studied in normal subjects and in patients with various car- diac diseases (1-10). With adequate doses of the drug a significant reduction of the systemic blood pressure was observed in almost all cases. In many patients, particularly those with pulmonary hypertension, a reduction of the pulmonary artery pressure was also seen. However, the pulmonary "capillary" or pulmonary artery wedge pressures were recorded in only a small number of cases and changes of resistances in the pulmonary cir- cuit were seldom studied.