Blood Flow and Lipid Transport in a 45 Degree Bifurcation

Abstract

Atherosclerotic lesions may occur in arteries where there are major changes in flow patterns, e.g. bifurcations and junctions. As in an arterial stenosis, disturbed flows in such areas may affect the transport of atherogenic macromolecules and lipids from flowing blood to the luminal surface. The altered transfer of these substances at the junctions, in turn, might result in enhanced lipid infiltration, leading to atherosclerotic lesions. To predict the possible locations of atherogenesis, we used a two-dimensional bifurcation as a human carotid bifurcation model to simulate theoretically the blood flow and to assess quantitatively the effect of a disturbed flow on the luminal surface lipid concentration at the blood/vessel wall interface. The results show that disturbed flows at arterial bifurcations and surgically created junctions enhance atherogenic substance and lipid transfer from flowing blood toward vessel walls. Therefore, these areas have the potential of developing atherosclerotic lesions and are subject to the late failures of grafting resulting from intimal hyperplasia, atherogenic process and anastomotic false aneurysm associated with lipid infiltration.