Objective: Elastic properties of the vessel wall are associated with atherosclerosis and major cardiovascular events. Several physiological and pathological conditions can affect arterial elasticity, but few studies have considered the role of hemorheological parameters. The present study aimed to investigate the relationship between hemorheological parameters and vascular stiffness in the carotid artery district.
Methods: One hundred and two individuals were enrolled. Blood and plasma viscosity were measured by a cone-plate viscometer (Wells-Brookfield DV-III, Stoughton, U.S.A.). Echo-Doppler evaluation of carotid arteries was performed in order to calculate elastic indexes (strain, β-stiffness index and distensibility). The association between hemorheological parameters and carotid elasticity indexes was assessed by simple and multiple regression analyses.
Results: In simple correlation analysis, only blood viscosity was directly associated with β-stiffness index (r = 0.20, p = 0.05) and inversely with strain (r =-0.26, p = 0.01) and distensibility (r =-0.34, p = 0.001). After adjusting for cardiovascular risk factors, blood viscosity, but not plasma viscosity or hematocrit, was independently associated carotid arterial measures, together with age, obesity, hypertension, and dyslipidemia.
Conclusions: The results of the present study demonstrate a strong association between blood viscosity and common carotid elasticity indexes.
Keywords: Blood viscosity; carotid elasticity; plasma viscosity; ultrasound.