Impact of bifurcation angle on hemodynamics and oxygen delivery in stenosed arterial junctions

Cardiovascular diseases, largely driven by atherosclerosis-induced stenosis, remain the leading cause of mortality worldwide. The bifurcation of the brachiocephalic trunk into the subclavian and common carotid arteries is particularly susceptible to disturbed hemodynamics and plaque accumulation. This study presents a computational analysis of the impact of stenosis and bifurcation geometry (45°, 60°, and 75°) on blood flow and oxygen transport using COMSOL Multiphysics®. Pulsatile flow conditions were modeled with coupled laminar flow and transport of diluted species modules to evaluate velocity, wall shear stress (WSS), and oxygen concentration. Results show that stenosis leads to a significant increase in peak systolic velocity (up to ∼31%) and localized WSS (peaking at 16 Pa), especially at lower bifurcation angles. Wider bifurcation geometries (75°) resulted in pronounced flow separation, vortex formation, and reduced oxygen delivery, with concentrations falling as low as 0.10 mol/m 3 in critical downstream regions. These hemodynamic disturbances were most severe in the presence of both wide bifurcation angles and stenotic narrowing. The model was validated against previous numerical and experimental studies, confirming its accuracy. The findings underscore the importance of considering arterial geometry in diagnosing vascular risk and optimizing intervention strategies. Integrating hemodynamic and oxygen transport analysis provides a more comprehensive understanding of stenosis progression and offers a foundation for personalized cardiovascular treatments.