The natriuretic peptide family consists of atrial natriuretic peptide (ANP), brain natriuretic peptide (BNP) and C-type natriuretic peptide (CNP). These peptides are produced in the heart and are well known to serve as circulating hormones in regulating renal function and vascular tone. Recently the presence of the natriuretic peptide receptors in the heart has been reported and interest in their role as autocrine/paracrine factors which modulate cardiac function and the coronary circulation has been growing. Our laboratory and others have reported effects of the natriuretic peptide family or its common second messenger, cyclic guanosine monophosphate (cGMP), on myocardial or ventricular function and coronary vascular tone in vitro and in vivo. The growing body of data concerning the role of the natriuretic peptide family as autocrine/paracrine factors in the heart should lead to the further elucidation of its pathophysiologic role in the development of heart failure and its potential clinical utility in the diagnosis and treatment of heart failure.