The aim of the study was to assess the use of gelofusine and voluven for acute normovolemic hemodilution at cardiac surgery under extracorporeal circulation (EC). Sixty-seven patients with coronary heart disease were examined. Heart rate, total peripheral vascular resistance, pulmonary pressure, pulmonary artery wedge pressure, oxygen delivery and consumption, central venous pressure, arteriovenous oxygen difference, oncotic pressure, and postoperative clinical course were studied. No significant group differences were found in indices, other than arteriovenous oxygen difference, after acute normovolemic hemodilution and in central venous pressure following 6 hours of EC termination. The administration of gelofusine caused a more steady-state oxygen-transport function of the circulatory system. The use of the agent for acute normovolemic hemodilution at cardiac surgery under EC is more economically justified than that of volumen.