A Hemodynamic Shear Stress-driven CFD Model to Assess Risk of Atherosclerotic Progression

Presenter: Harshawardhan Patil, Mechanical Engineering

Authors: H. Patil, A. Untaroiu

Abstract: Hemodynamics of blood flow have been linked to influence atherosclerosis, a condition that describes fatty deposits on the inner walls of arteries and a narrowing of the arterial lumen (known as a stenosis). This study investigates how wall shear stress patterns are influenced by stenosis severity and its orientation relative to the bulk flow affects the flow dynamics. The study aims to reveal clinician-oriented insights that aid in atherosclerosis diagnosis and/or management. We computationally analyzed blood flow in 4 stages of carotid artery stenoses (0%, 30%, 60% and 80%) at 3 different ‘angles of attack’ (orientation relative to bulk flow) in Ansys Fluent. We employed a Newtonian rheology of blood and utilized the low Reynolds k-w turbulence model. Time-Averaged Wall Shear Stress (TAWSS) below the established threshold of 0.4 Pa is observed in the internal carotid artery region, consistent with findings in literature. Progressively severe stages of stenosis experience higher TAWSS, while the angle of attack influences the onset and persistence of turbulence. Turbulent production is known to correlate positively with platelet activation, thereby promoting thrombus formation. We qualitatively rank the different artery models based on the risk of atherosclerotic progression.