Atrial natriuretic factor in acute and chronic cardiac failure

Water, sodium, and potassium balance and urinary excretion of norepinephrine and aldosterone were investigated in rats with left ventricular failure due to left ventricular infarction, and measurements were obtained of plasma levels of atrial natriuretic factor (ANF). Increased plasma levels of ANF in relation to the size of the infarction and to the right atrial and left ventricular end-diastolic pressure were found. The augmented levels of ANF were not able to prevent an accumulation of sodium in the rats with myocardial infarction in which urinary excretion of norepinephrine and aldosterone was unchanged in comparison to control values. Plasma levels of ANF in the pulmonary artery, aorta, and renal vein of six conscious dogs were studied during the development of heart failure due to rapid right ventricular pacing. A threefold increase in ANF was found: ANF levels did not differ between the pulmonary artery and the aorta, but a reduction in ANF of about 30% was reported in the renal vein in comparison to the arteries. A close positive correlation between right atrial pressure and plasma levels of ANF was noted. No correlation could be demonstrated between mean pulmonary arterial pressure and ANF or between the stimulated plasma renin concentration and plasma ANF values.