Erythrocyte aggregation as derived from blood viscoelasticity - clinical studies

Viscoelasticity of blood results primarily from the reversible network building, aggregation and disaggregation of red blood cells (RBCs) and from their elastic deformations. By measuring viscoelasticity one can differentiate during an oscillating shear experiment between elastic and viscous deformations in order to get some information about the elastic components of the fluid. Blood viscoelasticity was determined here with an oscillating capillary rheometer. The changes in the elastic parameters of blood viscoelasticity with increasing shear stress reflect the changes in RBC aggregates. An aggregation index (AI) was described to measure pathological changes of RBCs. The values of AI for healthy and for several pathological blood samples have been demonstrated. The results of various types of therapeutical treatment on hemorheological parameters, as well as their predictive potential in a prospective study on patients with arterial occlusive deseases have also been shown.