Hemodynamic and mechanical factors acting on arteries

Abstract

Arteries are permanently exposed to mechanical stress. Mechanical stress can be divided according to their nature, either tensile stress or shear stress. Tensile stress corresponds to changes in dimension according to changes in forces applied on the vessel. Shear stress is of a different nature; it corresponds to the friction of viscous fluid (here the blood) on the inner surface of the vessel (here the endothelium). It is to be noted that direct measurement of stress is difficult in vivo and that stress is most of the time deduced from stretch (elongation) and force (derived from pressure). Stress can also be derived from mechanical modelling.