Effects of Iloprost on Blood Rheology and Tissue Perfusion in Patients with Intermittent Claudication: Results of a Double-blind Placebo-controlled Study

The effects of an infusion of a single dose of Iloprost (from 0.5 up to a maximum of 2 ng/kg/min for six hours) in patients with stage II peripheral vascular disease (PVD) on blood rheology and tissue perfusion were determined in a double-blind placebo-controlled study using repeated treadmill exercise test to stress leg circulation. Blood viscosity (BV) at low shear, soluble P-selectin levels (expression of platelet activation), unfractioned leukocyte and erythrocyte filterability rates (using a constant-flow positive-pressure system), plasma fibrinogen concentration, haematocrit, leukocyte and platelet counts were measured in two matched groups of 8 PVD patients before and after treatment. Transcutaneous oxygen pressure (TcPO2) during controlled ischaemia was also measured. Controlled peripheral ischaemia generated an impaired haemorheological profile. Iloprost reduced the impairments in BV and the filterability rates of unfractioned leukocytes, inhibited platelet activation and improved erythrocyte deformability. These improvements were associated with significant shortening of the TcPO2 half recovery time, indicating that ischaemic damage had been contained.