Denopamine was orally administered for more than 12 months to patients with chronic heart failure on maintenance hemodialysis. The plasma level in subjects treated with denopamine at 30 mg/day tended to be higher than that in subjects on 15 mg/day. There was no gradual increase in plasma level as the duration of therapy prolonged. Left ventricular end-diastolic and end-systolic diameters as well as ejection fraction on echocardiography showed a tendency to be improved by denopamine. Similarly, the cardiothoracic ratio was improved temporarily. No adverse effects were detected by electrocardiography and laboratory tests. These observations suggest that denopamine is safe and effective for hemodialysis patients with chronic heart failure.