A fluid-structure interaction finite element analysis of pulsatile blood flow through a compliant stenotic artery

A new model is used to analyze the fully coupled problem of pulsatile blood flow through a compliant, axisymmetric stenotic artery using the finite el ement method. The model uses large displacement and large strain theory for the solid, and the full Navier-Stokes equations for the fluid The effect o f increasing area reduction on fluid dynamic and structural stresses is pre sented Results show that pressure drop, peak wall shear stress, and maximum principal stress in the lesion all increase dramatically as the area reduc tion in the stenosis is increased from 51 to 89 percent. Further reductions in stenosis cross-sectional area, however, produce relatively little addit ional change in these parameters due to a concomitant reduction in flow rat e caused by the losses in the constriction. Inner wall hoop stretch amplitu de just distal to the stenosis also increases with increasing stenosis seve rity, as downstream pressures are reduced to a physiological minimum. The c ontraction of the artery distal to the stenosis generates a significant com pressive stress on the downstream shoulder of the lesion. Dynamic narrowing of the stenosis is also seen, further augmenting area constriction at time s of peak flow. Pressure drop results are found to compare well to an exper imentally based theoretical curve, despite the assumption of laminar flow.