Biomechanical Analysis of Wall Remodeling in Elastic Arteries With Application of Fluid–solid Interaction Methods

Abstract

The effects of age-related hypertrophic remodeling of the thoracic aortic wall on mechanical stresses are quantified using the fluid–solid interaction method. Boundary conditions include physiological flow and pressure waves. Fluid and solid governing equations are solved using the loose coupling method. The results show alteration of hemodynamic and wall mechanical parameters by the remodeling process, including reduction in maximum circumferential stress and lower shear stress fluctuation with smaller portion of negative value and smaller maximum value. Such characteristics are indicators of the reduction of risk of endothelial injury. Remodeling causes elevation of the stress phase angle, an indicator of interaction between shear and circumferential stresses that causes triggering of endothelial cell proliferation, which is necessary for coverage of extra surface required by remodeling. The improvement by remodeling is limited by age-related structural changes such as elastin dysfunction and disorganization of structural components.

The effects of stenosis severity on the hemodynamic parameters—assessment of the correlation between stress phase angle and wall shear stress

“…12-16. The results show that mean WSS in the pre-stenotic area is not much sensitive and it only decreases slightly, while SPA partly increases in this area, which is in agreement with that of Niroomand et al (2007). In the proximal shoulder area of the stenosis as the stenosis severity increases, mean WSS increases.…”

Effects of Cyclic Stretch Waveform on Endothelial Cell Morphology Using Fractal Analysis

“…As an example, a 25% decrease in wall shear stress has been reported in an elastic model compared with a solid model of the arterial wall (32). In hypertensive‐induced remodeling of the arterial wall, it has been shown that by elevation of the blood pressure pulse, not only the circumferential stress pulse is changed, but also the shear stress wave alters markedly, and hence, for a proper remodeling algorithm, both stresses should be considered (33).…”

“…Therefore, application of in vivo cyclic stretch on endothelial cells due to pulsatile pressure might influence cell morphology directly by circumferential stress and indirectly by shear stress due to coupling of wall mechanics and blood hemodynamics. In addition to shear and circumferential stress values, the phase shift between two stress waves is also a determinant (29,33).…”

Effect of Continuous Arterial Blood Flow of Intra-Aorta Pump on the Aorta - A Computational Study

“…Due to increasing number of causalities of cardiovascular diseases (CVD), blood flow in large arteries has been topic of extensive research [7,8]. The structure of the arterial network and the relevant geometrical and mechanical parameters are influenced by the governing principles in arterial function, growth, remodeling, and adaptation [9]. So it's necessary to research the laws to guide the clinical operation and long-term treatment of ventricular assist patients.…”