Mathematical Modeling of Hemodynamic Flow in Coronary Arteries Under Stenotic Conditions

Abstract

Coronary artery stenosis alters vascular geometry and can alter local hemodynamics, in terms of pressure loss, wall shear stress and flow velocity significantly. Quantitative modeling is a constructive tool to examine such effects under controlled conditions, especially when one would like to isolate the contribution of stenosis severity. The present work develops a reduced-order mathematical model of hemodynamic flow in a coronary artery with localized stenosis and evaluates how stenosis severity influences pressure gradient, pressure drop, wall shear stress, and velocity distribution. The artery is represented as a straight axisymmetric vessel with a Gaussian-shaped constriction, and blood flow is modeled as steady, incompressible, laminar, and Newtonian in a rigid domain. A Poiseuille-type formulation with spatially varying radius is used to compute hemodynamic quantities, and the domain is discretized along the axial direction. Simulations are performed for stenosis severities of 0.2, 0.4, 0.6, and 0.8. The results show that increasing stenosis severity produces strongly nonlinear hemodynamic responses. The minimum radius decreases from 2.4 mm to 0.6001 mm, while pressure drop increases from 20.0570 Pa to 541.3338 Pa. Peak wall shear stress rises from 0.4835 Pa to 30.9375 Pa, and peak velocity at the stenosis throat increases from 0.1658 m/s to 2.6521 m/s, whereas upstream velocity remains largely unchanged. These findings indicate that localized geometric constriction significantly amplifies flow resistance and concentrates mechanical stress within the stenosed region. The proposed framework provides a computationally efficient basis for parametric analysis and may support further extensions toward more physiologically detailed coronary flow models.