The objective of the study was the evaluation of natriuretic peptides in ischemic heart disease. Atrial and brain peptides (ANP, BNP) were elevated in patients with ischemic heart failure, as compared with patients with angina without over failure, and controls (p < 0.01). BNP/ANP ratio was higher in NYHA class IV than in class III patients (2.67 +/- 0.87 vs. 1.52 +/- 0.59, respectively). Patients in the angina group, in whom elevated BNP or ANP was found, had subclinical systolic or diastolic dysfunction. There was inverse correlation between BNP, ANP and the left-ventricular ejection fraction (each r = 0.78, p < 0.001). We conclude that BNP is elevated as a result of myocardial dysfunction, but not of ischemia and seems to be a better index of disease stage and prognosis than ANP.