Carotid artery hemodynamics before and after stenting: A patient specific CFD study

Quantitative assessment of the hemodynamic impact of carotid artery stenting (CAS) represents an important ingredient to understand the CAS long-term outcomes, which are still a matter of clinical debate. Although computational fluid dynamics (CFD) has been extensively used for the biomechanical analysis of carotid arteries in healthy and stenotic conditions, there are few contributions in the literature dealing with post-stenting conditions because (i) current medical images do not have sufficient resolution to accurately reconstruct the stent geometry, and (ii) the generation of a body-fitted mesh of the stent-artery configuration is cumbersome. Motivated by these considerations, the present study proposes a numerical approach able to implicitly account for the stent geometry in the post-operative patient-specific hemodynamic CFD analysis by introducing velocity penalty terms in the weak form of the equations governing blood flow in arteries. Such an approach allows us to compare different patient-specific CAS scenarios, ranging from a healthy carotid to a post-stenting configuration after the treatment of a severe stenosis, and paves the way for rapid CFD-based investigations of the hemodynamic impact of novel endovascular devices with complex grid designs. Test computations as well as patient-specific CAS simulations are presented in this paper, with good results obtained in all cases.