Numerical investigation and prediction of atherogenic sites in branching arteries.

Atherosclerosis, a disease of large- and medium-size arteries, is the chief cause of death in the US and most of the western world. It is widely accepted that the focal nature of the disease in arterial bends, junctions, and bifurcations is directly related to locally abnormal hemodynamics, often labeled "disturbed flows." Employing the aorto-celiac junction of rabbits as a representative atherosclerotic model and considering other branching blood vessels with their distinctive input wave forms, it is suggested that the local wall shear stress gradient (WSSG) is the single best indicator of nonuniform flow fields leading to atherogenesis. Alternative predictors of susceptible sites are briefly evaluated. The results discussed include transient velocity vector fields, wall shear stress gradient distributions, and a new dimensionless parameter for the prediction of the probable sites of stenotic developments in branching blood vessels. Some of the possible underlying biological aspects of atherogenesis due to locally significant /WSSG/-magnitudes are briefly discussed.