Association of Whole Blood Viscosity and Severe Extracranial Carotid Artery Stenosis

Objective: Carotid artery stenosis (CAS) is not only an important risk factor for cerebrovascular events but also can indicate generalized atherosclerosis. Hemorheological parameters are altered in CAS and chronic cerebrovascular disorders as well, but it is controversial whether hemorheological parameters could be markers of stenosis or atherosclerosis.
Material and Methods: We studied 154 patients with extracranial internal carotid artery stenting for symptomatic or asymptomatic severe CAS. Hematocrit total protein values of the patients included in the study were calculated using the De-Simone constant formula, low shear stress (LSR) and high shear stress (HSR).
Results: No statistically significant difference was found between the whole blood viscosities (LSR, HSR) of asymptomatic and symptomatic patients with carotid artery stenting (p=0.234, p=0.165).
Conclusion: Although hemorheological parameters are impaired in both CAS and chronic cerebrovascular disorders, the severity of stenosis cannot be detected based on hemorheological parameters. Our investigation suggests that the alteration of hemorheological parameters could indicate carotid atherosclerosis.

Keywords: Carotid artery stenosis, hematocrit, viscosity, carotid artery stenting