Analysis of atherosclerotic plaque formation in artery bifurcations

The role of geometric and fluid-dynamic parameters in atherogenesis is investigated by numerical solution of the relevant steady laminar flow equations, i.e. a finite-element solution of the steady-state 2-D and 3-D Navier-Stokes equations. The flow geometry representing an aortic bifurcation is a two-dimensional symmetric branching channel with and without stenosis. Since carotid flow also remains essentially constant, a three-dimensional tubular geometry is assumed for carotid artery bifurcations. The velocity fields, including reverse-flow regions, pressure profiles, and wall shear-stress distributions for different Reynolds numbers, wall curvatures, and bifurcation angles are of particular interest. The flow analysis is extended to include two new models. One is for the pseudotransient formation of plaque at sites, with deposition rates defined by the physical characteristics of the flow. The other model considers the fluid and the particles as interacting continua and describes the particle trajectories in order to determine the critical 'landing' sites, i.e. the wall areas of plaque formation. The validated computer simulation model is capable of analyzing the fluid-particle dynamics.<
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