Dynamic response of arterial walls in vivo.

By the use of non-linear constitutive equations suitable for the characterization of anisotropic viscoelastic incompressible materials under finite deformations, the paper is devoted to analytical study on the dynamic stress field in arterial walls under the combined action of the pressure of blood on the inner surface and the pressure from the neighbouring components of the body on the outer surface. By using short time range approximations, the magnitudes of the radial and circumferential stresses are examined at various locations of the vascular wall and for different time intervals. It is observed that consideration of the mechanical influence of the external tissues and the inertial forces makes the derived stress field quite close to the experimental results reported recently by Fung et al. (1979), in comparison to the results of Cheung et al. (1972), who did not consider the aforementioned factors. It can thus be concluded that these factors need be considered for the studies of the stress field in arteries in vivo.