Computer simulation and geometric design of endarterectomized carotid artery bifurcations

The main goal of this computational study is to establish surgical guidelines for optimal geometries of carotid endarterectomy reconstructions that may measurably reduce postoperative complications, that is, thrombosis, stroke, and/or restenosis. The underlying hypotheses are that nonuniform hemodynamics, or "disturbed flows," are linked to arterial diseases and consequently that minimization of "disturbed flow" indicators leads to geometric bifurcation designs that lower postoperative complication rates. Considering transient 3-D laminar blood flow in partially occluded, in-plane, rigid-wall carotid artery bifurcations, the results presented include time-averaged indicators of "disturbed flow", such as the wall shear stress, spatial wall shear stress gradient, and wall shear stress angle deviation. In addition, trajectories and deposition patterns of critical blood particles (i.e., monocytes) are shown and evaluated. Within given physiological constraints, the vessel geometry was then changed in order to reduce the magnitudes of key indicators associated with thrombosis (i.e., blood clot formation) or restenosis (e.g., renewed atherosclerosis and/or hyperplasia). The quantitative results and knowledge base generated will be crucial for future clinical trials.