title: Stress analysis of fracture of atherosclerotic plaques: crack propagation modeling.
abstract: Traditionally, the degree of luminal obstruction has been used to assess the vulnerability of atherosclerotic plaques. However, recent studies have revealed that other factors such as plaque morphology, material properties of lesion components and blood pressure may contribute to the fracture of atherosclerotic plaques. The aim of this study was to investigate the mechanism of fracture of atherosclerotic plaques based on the mechanical stress distribution and fatigue analysis by means of numerical simulation. Realistic models of type V plaques were reconstructed based on histological images. Finite element method was used to determine mechanical stress distribution within the plaque. Assuming that crack propagation initiated at the sites of stress concentration, crack propagation due to pulsatile blood pressure was modeled. Results showed that crack propagation considerably changed the stress field within the plaque and in some cases led to initiation of secondary cracks. The lipid pool stiffness affected the location of crack formation and the rate and direction of crack propagation. Moreover, increasing the mean or pulse pressure decreased the number of cycles to rupture. It is suggested that crack propagation analysis can lead to a better recognition of factors involved in plaque rupture and more accurate determination of vulnerable plaques.
authors.affiliation: Cardiovascular Engineering Lab, Faculty of Biomedical Engineering, Amirkabir University of Technology (Tehran Polytechnic), Tehran, Iran.
authors.forename: Alireza
authors.initials: A
authors.lastname: Rezvani-Sharif
authors.affiliation: Cardiovascular Engineering Lab, Faculty of Biomedical Engineering, Amirkabir University of Technology (Tehran Polytechnic), Tehran, Iran. tafazoli@aut.ac.ir.
authors.forename: Mohammad
authors.initials: M
authors.lastname: Tafazzoli-Shadpour
authors.affiliation: Atherosclerosis Research Center, Baqiyatallah University of Medical Sciences, Tehran, Iran.
authors.forename: Davood
authors.initials: D
authors.lastname: Kazemi-Saleh
authors.affiliation: Department of Surgical and Clinical Pathology, Tehran Heart Center, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Maryam
authors.initials: M
authors.lastname: Sotoudeh-Anvari
mesh_terms: D003198:Computer Simulation; D003324:Coronary Artery Disease / Q000473:pathology* / Q000503:physiopathology*; D003331:Coronary Vessels / Q000473:pathology* / Q000503:physiopathology*; D055119:Elastic Modulus; D005260:Female; D020342:Finite Element Analysis; D006801:Humans; D008297:Male; D008875:Middle Aged; D008953:Models, Anatomic; D008955:Models, Cardiovascular; D058226:Plaque, Atherosclerotic / Q000473:pathology* / Q000503:physiopathology*; D033081:Shear Strength; D013314:Stress, Mechanical
keywords: Atherosclerotic plaque; Fatigue; Finite element method; Fracture mechanics; Myocardial infarction