Computational modeling of luminal flow-driven mass transport in coronary arteries for optimizing drug-eluting stent efficacy

This study explores the influence of luminal flow and drug diffusivity on drug transport from a well-apposed drug-eluting stent with struts of square cross-section. A theoretical approach is adopted by constructing a numerical model that captures key aspects of the physiological environment. In this model, drug movement within the lumen is described as an unsteady convection-diffusion process, whereas transport through the arterial tissue is treated as a diffusion phenomenon. Assuming axis symmetry and employing a cylindrical coordinate system, the marker-and-cell (MAC) technique is used to solve the governing flow and transport equations for stent-mediated drug delivery. The model yields quantitative insights into how parameters such as Reynolds number and Peclet number influence wall shear stress and drug dispersion within both the lumen and the arterial tissue. The results, presented graphically, indicate that increasing the Peclet number reduces drug concentration in both regions. Furthermore, the simulations reveal two distinct recirculation zones—proximal and distal to the strut—with the distal region being notably more prominent. This finding aligns with earlier studies, thereby reinforcing the reliability of the proposed numerical model.