HAeMODYNAMIC EFFECTS OF HISTAMINE IN MITRAL STENOSIS

Abstract
Eight patients with mitral stenosis were subjected to right heart catheterization, and observations were made at rest, during exercise, and during an intravenous infusion of histamine. At rest and during exercise the patients had hemodynamic and respiratory changes characteristic of mitral stenosis. Histamine infusion caused, among other things, an increase in the cardiac output, a decrease of the pulmonary vascular resistance, and a lowering of arterial O2 saturation. The mechanisms of action of histamine on the circulation and respiration in mitral stenosis are discussed.