Role of oscillatory shear index in predicting the occurrence and development of plaque

The paper presents theoretical basis and results obtained by calculation of blood flow in coronary artery bifurcation, whereby the emphasis is placed on the plaque occurrence analysis based on oscillatory shear index (OSI). OSI is the temporal fluctuation of low and high average shear stress. The endothelial or wall shear stress is a major factor that affects the formation of plaque phenomenon. There are complex hemodynamic conditions in these areas where local fluid flow dictates the occurrence and development of plaque. Favorable conditions for the plaque development occurring in areas characterized by low shear stress, while areas with higher values of OSI index are not susceptible. Arterial bifurcations are the places in vascular tree where atherosclerosis mainly occurs. OSI index response to the appearance of plaques in the common coronary artery and branches are considered on three out of eight possible combinations of plaque locations. Algorithm for the calculation of OSI index are embedded in software PAK-F and the results are written in FEMAP neutral and Paraview VTK file format.