Influence of pulsatile inlet waveforms on hemodynamics in a severely stenosed carotid artery: A CFD study

Carotid artery stenosis is a major contributor to ischemic stroke, a leading cause of death and long-term disability worldwide [Lopez et al., Lancet 367, 1747–1757 (2006) and WHO, Stroke fact sheet, 2023]. Accurate hemodynamic modeling of stenosed carotid arteries is essential for understanding atherosclerosis progression and developing computational tools for stroke risk assessment [Lloyd-Jones et al., Circulation 121, e46–e215 (2010) and Hankey et al., Stroke 33, 1034–1040 (2002)]. This study presents a three-dimensional computational fluid dynamics (CFD) investigation of pulsatile blood flow through an idealized carotid artery with 75% area reduction, comparing a simplified sinusoidal inlet waveform against a physiologically realistic waveform reconstructed from 16 Fourier harmonics. Blood is modeled as an incompressible Newtonian fluid with a rigid vessel wall, and the low-Reynolds-number k-ω turbulence model is employed. Wall shear stress (WSS), velocity, centerline pressure, and streamline patterns are evaluated at early systole, peak systole, and diastole. Results show close agreement between models at peak systole but significant differences at low-flow phases in WSS, centerline velocity, and recirculation zone size, underscoring the necessity of physiologically accurate inlet conditions in carotid CFD studies.