Determination of hemodynamic risk for vascular disease in planar artery bifurcations

Understanding hemodynamics in blood circulation is crucial in order to unveil the mechanisms underlying the formation of stenosis and atherosclerosis. In fact, there are experimental evidences pointing out to the existence of some given vessel configurations that are more likely to develop the above mentioned pathologies. Along this manuscript, we performed an exhaustive investigation in a simplified model aiming to characterize by means of physical quantities those regions and configurations in vessel bifurcations that are more likely to develop such pathologies. The two-fold analysis is based, on the one hand, on numerical simulations (via CFD) and, on the other hand, on experiments realized in an ad-hoc designed polydimethylsiloxane (PDMS) channel with the appropriate parameters and appropriate fluid flows. The results obtained demonstrate that low velocity regions and low shear stress zones are located in the outer walls of bifurcations. In fact, we found that there is a critical range of bifurcation angles that is more likely to vascular disease than the others in correspondence with some experimental evidence. The effect of the inflow velocity on this critical range is also analyzedWe gratefully acknowledge financial support by the Spanish Ministerio de Economía y Competitividad and European Regional Development Fund under contract MAT2015-71119-R AEI/FEDER, UE, and by Xunta de Galicia under Research Grants No. GPC2015/014 and ED431B 2017/64 Xunta de Galicia/FEDER. APM, AOC and VPM belong to the CRETUS Strategic Partnership (AGRUP2015/02) and MA and MTFA to the AGRUP2015/11(PC034). All these programs are co-funded by FEDER (UE). MA acknowledges a Pre-Doctoral Fellowship from Xunta de Galicia (Spain) financed by the Secretaría Xeral de Universidades and the Fondo Social Europeo (FSE)S