Biomechanical Analysis Of Atherosclerotic Plaque

Instability and rupture of atherosclerotic plaque can lead to cardiovascular diseases such as coronary syndrome.The process of the plaques rupture of atherosclerosis involves many factors,such as stress distribution,plaque morphology,and blood conditions.At the same time,in the process of plaque rupture,biomechanics is also generally believed to play an important role.Based on the common plaque models with the theoretical knowledge of fluid mechanics,we propose a plaque instability model——There is a cavity or microcalcification interlayer between the fibrous cap and the lipid core with a size of about 10 microns.The finite element method is used to analyze the stress distribution of plaques in different biological environments.Numerical simulation results show that the maximal stress conce ntration and torque occur in the AP shoulder.Secondly,a larger stres s distribution can be found along the direction of the two shoulders of atherosclerotic plaque.There is a relatively large stress distributi on in the smaller part in an AP structural combination.The model c an well describe the acute cardiovascular and cerebrovascular diseases appearance,which is produced by the plaque disruption leading to th e acute coronary syndromes,myocardial infarction,and sudden stroke.The results show that the mechanical stresses in AP play an import ant role in the AP rupture process,and this may be used for predicti ng plaque vulnerability and rupture.For the model of the interlayer plaque with defects,except for the larger shoulder stress,the stress concentration phenomenon also appears in the areas with cavities or the calcified areas.Compared with the case of the uniform plaque,the former will increase the stress at the boundary of fiber cap by 2 to 6 times,which will lead to the instability of plaque,and even lead to the peeling of fiber cap from the surface of lipid nucleus and the rupture of plaque,thus increasing the risk of plaque instability.The simulation results of this model also verify some phenomena in autopsy,that is,in addition to the easy rupture of the plaque shoulder,the rupture in the calcified and defected areas near the fiber cap also occurs occasionally.Our model can well explain some cardiovascular diseases caused by atherosclerosis.