Atrial natriuretic peptide in patients with severe heart failure.

Alpha atrial natriuretic peptide was measured in plasma in 7 patients with severe heart failure before and after the administration of the synthesized substance. An inverse correlation was found between basal plasma levels of alpha atrial natriuretic peptide and cardiac output. Incremental bolus injections of synthetic alpha atrial natriuretic peptide and the continuous infusion for 30 minutes resulted in a decrease of peripheral vascular resistance, an increase of cardiac output and a decrease of blood pressure. Plasma aldosterone was markedly reduced in each patient by the administration of atrial natriuretic peptide and a small but significant decrease of plasma cortisol was found. Diuresis, urinary sodium and potassium excretion were enhanced. No significant changes were observed concerning adrenocorticotropic hormone, plasma renin concentration, plasma norepinephrine and vasopressin and the plasma levels of 6-keto-prostaglandin F1-alpha and prostaglandin E2.