Simulating the mechanical response of artery walls by high order finite elements

Prof. Zohar Yosibash

Jan. 14, 2011, 2:30 p.m. K 153C

The healthy human artery wall is a complex biological structure whose
mechanical response is of major interest and attracted a significant amount of
research, mainly related to its passive response. Herein we present a high-order
FE method for the treatment of the compressible hyper-elastic constitutive
model for the passive response based on a transversely isotropic strain-energy-
density-function (SEDF). More specifically, we first address two variants of the
SEDF and augment it by a volumetric part which is neglected in most studies.
Numerical examples are provided to demonstrate the efficiency of the high-
order methods compared to classical h-FEMs, and thereafter the in
uence of
the slight compressibility on the results.
Although the active response (when smooth muscle cells are activated) has a
significant in
uence of the overall mechanical response of the artery wall, it
has been scarcely investigated because of the difficulty of representing such
an in
uence in a constitutive model and lack of experimental evidence that
can validate such models. This active response is strongly coupled with the
passive response because of the mutual interaction (smooth muscle cells react
as a function of the mechanical response). In this presentation, we provide ex-
perimental evidence of the strong in
uence of the active response and propose
di erent approaches for its implementation using high-order FE methods.