Recent studies have uncovered the pivotal role that valvular interstitial cells play in the
aortic valve system. The valvular interstitial cells regulate the extracellular matrix, maintain
homeostasis, and modulate pathology, among other vital functions. The inherent connection
between the aortic valve as an organ and its constituent cells may explain the shortcoming of
traditional biomechanical modeling, particularly when the goal is to understand the cause,
evolution, treatment, and prevention of disease.
Multiscale modeling of aortic valves has recently emerged, but is relatively nascent and
much is missing from the literature. Most notably is the lack of a coupled multiscale model of
the aortic valve, wherein the biomechanics of the aortic valve organ and its constituent cells
impact one another. In this work, we investigate a novel multiscale approach to modeling
aortic valve tissue that is coupled, i.e., biomechanical events occurring at disparate length
scales are simultaneously captured.
We begin by presenting a model of aortic valve tissue that explicitly accounts for the
collagen bers that make up its microstructure and is consistent with experimental data.
We then apply this model in an FE2 (computational homogenization) framework to model
the aortic valve tissue as an organ and its constituent valvular interstitial cells. We show
the validity of such an approach and use it to argue the necessity of 3D multiscale modeling.
Finally, we apply the multiscale model to a calcied aortic valve to study the mechanical
behavior of the valvular interstitial cells in pathological tissue.