The clinical benefit of hypervolumetric hemodilution combined with venesection with 8 infusion of HES 200/0.5 10% (C2/C6 substitution ratio: 4.6) versus 8 Infusions of 250 ml Ringers' solution (p<0.05) was observed in this double blind placebo controlled cross- over study on 20 patients (12 men, 8 women) of an average age of 58 with complaints of pectangina but free coronary system and/or symptoms of dyspnea and ischemia during stress ECGs or with stress induced hypertension even at low stress levels. Only 2 patients presented mild side effects (hypertension, pectangina) without residual complaints. HES improved the microcirculation of the skin. HES increased blood fluidity relevantly with particular influence on the plasma viscosity, the erythrocyte aggregation and hematocrit. Both infusion solutions decreased the systolic and diastolic blood pressure. The patients with pectangina profited the most clinically so that this form of treatment should be limited to this patient group.A stepwise diagnostic procedure and treatment seems to be the most adept to relate to the pathophysiology of the multiform disease.