The Influence of the H.E.L.P. System on Yield Shear Stress in Vascular Disease

At a constant haematocrit ratio the yield shear stress (YSS) depends on the level of fibrinogen and on the influence of other plasma constituents, erythrocyte membrane changes on the red cells and fibrinogen interaction. The study of the influence of the H.E.L.P. system on the value of YSS was carried out in 9 patients with vascular disease (acute stroke - 3 patients -, multi-infarct dementia - 3 patients -, peripheral arteriosclerotic vascular disease - 2 patients - and coronary heart disease - 1 patient -) in the model of diluted plasma media varying in fibrinogen concentration. The H.E.L.P. system application significantly decreased the value of YSS (p<0.001), which was related to the parallel reduction of the fibrinogen level (p<0.001) and plasma viscosity (p<0.001). The significant coefficients of correlations were found out between following parameters: YSS and fibrinogen (p<0.001), YSS and plasma viscosity (p<0.001) and fibrinogen and plasma viscosity (p<0.00 1) .