Numerical simulation of low-density lipoprotein mass transport in human arterial stenosis - Calculation of the filtration velocity.

Accumulation of cholesterol and other atherogenic lipids such as low-density lipoprotein (LDL) in artery wall causes reduction of vessel diameter and artery stenosis. The study of the mass transfer of these large molecules in the wall with considering effective factors on lumen flow and different physiological factors is the subject considered nowadays. In this paper, results of two dimensional and axi-symmetric simulations of three different models of the artery with 60% stenosis under pulsatile blood flow are presented. Filtration velocity of LDL mass transport in the permeable artery wall and shear stress of blood flow are investigated using ADINA software Three different flow models are considered. In the first and second models, the filtration velocity considered as a given parameter and constant in arterial wall boundary, while in third model arterial wall considered as porous wall, the filtration velocity is calculated from pressure difference as an input parameter of the model. The results show that filtration velocity is strongly depend on geometry and it is not constant along the wall, contrary to simplified models. The results of concentration variations in lumen and wall illustrate the increase in near wall LDL concentration or concentration polarization.