Systemic Blood Pressure Response to Changes in Right Ventricular Function.

• Previous investigations have described areas in the circulation which, when appropriately stimulated, induce changes in total peripheral vascular resistance." Such receptor areas have been demonstrated in vessels of the lesser and greater circulation and three of the heart chambers. Whether similar vascular reflexes can originate in the right ventricle has been questioned. Although increasing pressure in the vascularly isolated left ventricle results in a decrease in total peripheral vascular resistance,'" a similar response is not elicited from the isolated right ventricle. A reflex increase in pulmonary blood flow without changes in systemic vascular resistance has been demonstrated following elevation of the systolic pressure in the intact right ventricle. The present report describes a pressor reflex which originates in the intact functioning right ventricle. An increase in systemic blood pressure and vascular resistance is shown after a rise in right ventricular systolic pressure. Experiments were performed in open-chest anesthetized dogs. The systemic vascular response was measured 1) with the circulation intact, 2) during total perfusion of the systemic circulation with a mechanical pump, 3) after the administration of atropine, and 4) following bilateral cervical vagotomy.