Influence of Surrounding Tissues on Biomechanics of Aortic Wall: A Feasibility Study of Mechanical Homeostasis

Previous research in cardiovascular mechanics has shown that mechanical factors strongly influence the growth and remodeling of blood vessels, thereby leading the hypothesis of mechanical homeostasis as a mechanism of regulating vascular adaptation [1]. Nevertheless, this assumption is mostly based on stress analysis of an idealized blood vessel. However, for the aorta, its motion is considerably limited by the surrounding tissue during the cardiac cycle, with the thickness of the posterior side significantly thinner than the anterior side (Fig. 1). In this work, we test the possibility of the existence of a homeostatic level of stress in the aorta using a linear plane-strain model that accounts for thickness variations and surrounding tissues. The results of this computational study show that the surrounding tissue, together with thickness variations, homogenizes the stress level of blood vessel under a physiological pressure, which implies that the mechanical homeostasis is still feasible even with thickness variations and the influence of the surrounding tissues in the aorta.