Endothelial dysfunction indicators and hemorheological properties in acute ischemic stroke

Abstract

We evaluated endothelial dysfunction and hemorheological indicators in acute ischemic stroke. The hemorheological indicators (blood viscosity, plasma viscosity, hematocrit, erythrocyte aggregation and deformability, fibrinogen concentration) were assessed three times: within the first 12 hours of the onset of symptoms and on day 3–5 and day 18–20 after hospitalization; the endothelial dysfunction indicators were examined on day 15–17 using a cuff test. Patients in the acute phase of ischemic stroke had pronounced changes in the hemorheological indicators that could be characterized as high blood viscosity syndrome. For example, we observed increased platelet aggregation that plays a key role in the blood viscosity value in blood vessels with low shear rates. We also observed reduced erythrocyte deformability at high shear rates. After treatment, patients had positive clinical dynamics according to neurological scales. Dynamics of the hemorheological indicators was as follows: erythrocyte aggregation decreased; blood viscosity tended to reduce; however, erythrocyte deformability tended to worsen. Therefore, the pathological changes in elastic properties of the erythrocyte membranes in stroke are not corrected by ongoing standard therapy. Assessment of the endothelial functional activity revealed that stroke patients had a decreased brachial artery response associated with reactive hyperemia and an increased response to the nitroglycerin test. The study demonstrated that treated patients with ischemic stroke had endothelial functional activity changes that manifested as a statistically significant increase in the endothelial dysfunction index. We concluded that the approach to stroke treatment requires complex pharmacological correction, in particular by means with the proven hemorheological activity.