MODELLING LDL ACCUMULATION IN THE CASE OF ENDOTHELIAL DYSFUNCTION
A. I. Sakellarios, P. Siogkas, T. Exarchos, K. Stefanou, C. V. Bourantas, L. Athanasiou, E. Fotiou, M. Papafaklis, K. K. Naka, L. K. Michalis, D. I. Fotiadis UDC: (612.13/.15:519.87; 616-008.9:577.125.8]:519.87)
The endothelium is responsible to keep the normal homeostasis of the vessels by regulating several biological and chemical mechanisms and responses. Nowadays it is evident that endothelial dysfunction is associated with an increased risk for plaque evolution. This work focuses on the modeling of LDL transport and accumulation in realistic geometries of coronary arteries in case of endothelial dysfunction. The Navier-Stokes equations and the convection- diffusion equations are utilized to simulate blood flow and LDL transport, respectively. Our model assumes shear stress dependent hydraulic conductivity, but also increased endothelial permeability in the case of endothelial dysfunction. For this purpose, the production of endothelial nitric oxide synthase (eNOS) is used for the calculation of nitric oxide (NO) synthesis. More specifically, the chemical reaction of NO production is modelled and the calculated concentration is taken into account to affect endothelial permeability. The obtained results demonstrate that endothelial dysfunction and NO concentration have an additional impact on LDL accumulation. Low concentration of NO, increases endothelial permeability resulting in an increased buildup of LDL molecules into the arterial wall. It appears that the LDL accumulation raises by up to 46% in case of endothelial dysfunction results which highlight the role of endothelial dysfunction on plaque evolution.