CARDIAC, HEMODYNAMIC AND RENAL FUNCTIONS IN CONGESTIVE HEART FAILURE DURING INDUCED PERIPHERAL VASODILATATION; RELATIONSHIP TO STARLING'S LAW OF THE HEART IN MAN*†

Abstract

Peripheral vasodilatation for one hour was produced by intravenous infusion of the ganglionic blocking agent, Arfonad [d-3,4(l[image],3[image]-dibenzyl-2[image]-keto-imidazolido)-l,2-trimethylenethiophanium d camphor sulfonate], in 12 cardiac subjects during conjestive heart failure, in 7 cardiac subjects after recovery of compensation and in 2 non-cardiac subjects. In all subjects intracardiac pressures and pressures in the systemic and pulmonic circulations fell (20 to 30%). In 8 of 10 subjects with low output congestive heart failure the lowering of vascular pressures was associated with an increase of cardiac output (15%) and a fall in A-V oxygen difference. In contrast, in 4 of 5 non-cardiac and compensated cardiac subjects cardiac output decreased (15%) and A-V oxygen difference increased slightly. In all subjects the excretion of water and sodium decreased, while renal hemodynamic functions changed variably and slightly. Because of the fall in arterial pressures the increase in cardiac output during vasodilatation in congestive heart failure was achieved without increase in cardiac minute or stroke work. In the non-cardiac and compensated cardiac subjects, minute and stroke work of the heart decreased during vasodilatation and this decrease was due more to the fall in arterial pressure than to the decrease in cardiac output. The fall in arterial pressures in these observations makes it difficult to determine whether Starling''s Law of the heart applied. If one accepts the condition of altered arterial pressures, then Starling''s Law may be considered to have held in the non-cardiac and compensated cardiac circulations but not in congestive heart failure, unless one assumes that cardiac function in all of these patients was on the flat portion of the cardiac work-filling pressure curve.