We studied the effects of recombinant human erythropoietin (rEPO) on angina pectoris in patients with chronic maintenance hemodialysis. We evaluated hemodynamic changes and exercise tolerance in 6 patients underwent symptom-limited treadmill exercise tests, before and 3-months after treatment with rEPO. Hemoglobin concentration and hematocrit increased significantly from 8.1 +/- 1.0 to 10.3 +/- 1.1 g/dl, from 25.7 +/- 2.7 to 31.5 +/- 2.5%, respectively. Exercise duration increased significantly from 291 +/- 68 to 396 +/- 77 sec. Maximal oxygen uptake (VO2max) also increased significantly from 18.3 +/- 3.3 to 24.2 +/- 3.4 ml/kg/min during correction of anemia. Systolic blood pressure (SBP) and pressure rate product (PRP) at rest, and at maximal exercise showed no significant changes, on the other hand ischemic ST change at maximal exercise decreased significantly from 1.2 +/- 0.7 to 0.2 +/- 0.3 mm under 3-months treatment. Our results suggest that improvement of exercise capacity and ST depression in patients with chronic hemodialysis is the outcome of increased coronary oxygen supply with unchanged cardiac oxygen demand after correction of renal anemia treated with rEPO.