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 w idely accepted that the focal nature of the disease in arterial bends, junctions, and bifurcations is directly related to locally abnormal h emodynamics, often labeled ''disturbed flows.'' Employing the aorto-ce liac junction of rabbits as a representative atherosclerotic model and considering other branching blood vessels with their distinctive inpu t wave forms, it is suggested that the local wall shear stress gradien t (WSSG) is the single best indicator of nonuniform flow fields Lading to atherogenesis, Alternative predictors of susceptible sites are bri efly evaluated. The results discussed include transient velocity vecto r fields, wall shear stress gradient distributions, and a new dimensio nless parameter for the prediction of the probable sites of stenotic d evelopments in branching blood vessels. Some of the possible underlyin g biological aspects of atherogenesis due to locally significant \WSSG \-magnitudes are briefly discussed.