Modelling Blood Flow and Analysis of Atherosclerotic Plaque Rupture under G-Force

In normal life the human body is quite often subjected to g-force. Prolonged exposure to such accelerations can generate significant effects on the blood circulation and its theological behavior depending on the configuration and geometry of the blood vessels. To analyze the effect of body acceleration in blood flow in arteries, blood is considered as a non-Newtonian fluid. The Navier-Stokes equations were used as the governing equations for an incompressible axisymmetric and fully developed flow. Atherosclerotic vascular disease is the leading cause of death in the developed world. It has been well accepted that over 50% of cerebral ischemic events are the result of rupture of vulnerable carotid atheroma and subsequent thrombosis. The wall shear stress of artery varies with body acceleration. So increased biomechanical stresses in the fibrous cap of atherosclerotic plaques contribute to plaque rupture and consequently to thrombosis and myocardial infarction and causes the blocks in small arteries. Thin fibrous caps and body acceleration are important determinants of increased plaque stresses. Here the velocities of blood through the artery and stress distribution within the plaque were simulated for varying g-force. Increased g-force and thinner fibrous cap led to larger plaque stress. This model suggests that g-force is critically related to plaque vulnerability. The degree of luminal stenosis from 10% to 70% and rupture stress of 300 kPa was chosen to indicate a high risk of plaque rupture.