Patient-specific CFD-PIV assessment of carotid hemodynamics and atherogenic risk

This study presents a combined numerical and experimental investigation of hemodynamics in a highly complex, patient-specific carotid artery with stenosis, reconstructed from magnetic resonance angiography images. Patient-specific boundary conditions were applied, using velocity measurements obtained via echo-Doppler from the same individual. The numerical analysis was validated through an experimental setup based on a cam-follower cylinder mechanism. This system offers a flexible and cost-effective solution capable of generating transient waveforms with high precision, effectively replicating physiological flow conditions. It is proposed as an alternative to conventional gear pump systems commonly reported in the literature, providing a more affordable and accurate option. The findings showed noticeable flow disturbances and recirculation throughout the cardiac cycle, particularly in the diastole, as well as regions of low and oscillatory wall shear stress associated with potential plaque progression. These are a result of the high complexity of the geometry, with distinct sharp edges as a result of plaque accumulation. Despite minor discrepancies between numerical and experimental velocity profiles, mainly due to wall compliance effects and the averaging effect of particle imaging velocimetry, the overall agreement validates the reliability of the methodology. The cam–follower–cylinder mechanism proved effective in reproducing physiological pulsatile flow.