The role of atrial natriuretic peptide levels in the pathogenesis or progression of idiopathic dilated cardiomyopathy was just beginning to be explored in 1987. Although Syrian hamster studies did not suggest a genetic deficiency as the primary cause of dilated cardiomyopathy in that model, it was thought possible that ANP production or levels were somehow involved in how the myocardium responds in idiopathic dilated cardiomyopathy patients.