Mechanical stresses in carotid plaques using MRI-based fluid–structure interaction models

Kock, S; Nygaard, Jens Vinge; Eldrup, Nikolaj; Fründ, Ernst-Torben Wilhelm; Klaerke, A; Paaske, William P.; Falk, Erling; Kim, W Yong

doi:10.1016/j.jbiomech.2008.03.019

Cited by 116 publications

(53 citation statements)

References 49 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…However, no significant differences were found between models with proximal cores vs. distal cores, indeed the stress levels were virtually identical. In a previous study [17], we found the longitudinal distribution of maximal stresses and plaque ruptures to be asymmetrically distributed in a group of symptomatic patients, with the majority occurring proximally to the plaque in line with the findings of Lovett et al…”

Section: Acknowledgementssupporting

confidence: 91%

“…strain relationship was used to specify the mechanical properties of the plaque components [17,18]. Two examples of velocity fields, first principal stress distributions, and velocity streamlines are presented in Figure 3.…”

Section: Resultsmentioning

confidence: 99%

“…Using a previously published method [17], a longitudinal 2D model was generated of the patient's carotid artery. In brief, the method uses a well-validated protocol with four magnetic resonance imaging (MRI) scans for segmenting plaque morphological components; lipid-rich necrotic core, fibrous cap, blood lumen, vessel wall, and calcifications (Figures 1(a) and (b)) [5].…”

Section: Methodsmentioning

confidence: 99%

See 2 more Smart Citations

The Effect of Carotid Plaque Morphology on Longitudinal Fibrous Cap Stress Levels

Thrysøe¹,

Stegmann²,

Eldrup³

et al. 2012

WJM

Self Cite

View full text Add to dashboard Cite

Background and Purpose: Rupture of vulnerable carotid atherosclerotic plaques is a major cause of stroke. Stress levels may reflect risk of rupture in patients with carotid atherosclerotic plaques. Features thought to influence the risk of plaque rupture include the degree of stenosis, lipid-rich necrotic core (LR-NC) size, and thickness of the protective fibrous caps. We used computational models to investigate the effect of these variables on fibrous cap stress levels. Methods: Two-way coupled fluid-structure interaction longitudinal 2D simulations were performed on a bifurcation model based on idealized geometry derived from a symptomatic patient. Models with varying degrees of stenosis (50% -95%), fibrous cap thicknesses (0.05 -1 mm), and LR-NC sizes (2 × 1 mm -6 × 3 mm) were simulated. The stress distribution for each model was calculated and peak principal stresses extracted. Regression analysis was used for assessing the relationship between the variables and stress levels. Results: Mechanical stresses increased with decreasing fibrous cap thicknesses (ß = -0.905, p < 0.001) and increasing LR-NC sizes (ß = 0.262, p < 0.001). The degree of stenosis (ß = 0.024, p = 0.344) and LR-NC placement (ß = -0.001, p = 0.979) had insignificant effects on mechanical stress levels. Conclusions: Thin-capped plaques with large atheromas, known predictors of plaque vulnerability, were shown to exhibit the greatest mechanical stress levels.

show abstract

Section: Acknowledgementssupporting

confidence: 91%

Section: Resultsmentioning

confidence: 99%

Section: Methodsmentioning

confidence: 99%

See 1 more Smart Citation

The Effect of Carotid Plaque Morphology on Longitudinal Fibrous Cap Stress Levels

Thrysøe¹,

Stegmann²,

Eldrup³

et al. 2012

WJM

Self Cite

View full text Add to dashboard Cite

show abstract

“…Flow velocities were measured using a phase-contrast turbo field echo sequence, whereas vessel wall deformation was depicted using a balanced gradient echo sequence. 5 …”

Section: Mri Protocolmentioning

confidence: 99%

Longitudinal Distribution of Mechanical Stresses in Carotid Plaques of Symptomatic Patients

Thrysøe

Oikawa

Yuan

et al. 2010

Stroke

Self Cite

View full text Add to dashboard Cite

Background and Purpose-Mechanical stress may contribute to plaque rupture in patients with carotid atherosclerosis. We determined longitudinal mechanical stresses in carotid atherosclerotic plaques and compared them with known markers of plaque vulnerability. Methods-Nineteen symptomatic patients scheduled for carotid endarterectomy underwent carotid MRI with a multicontrast protocol to characterize plaque morphology and geometry. Longitudinal 2-dimensional computational models were generated from the MRI data, and the mechanical stresses were calculated. Results-Peak longitudinal mechanical stresses occurred predominantly in the shoulder regions of the carotid plaque and correlated inversely with fibrous cap thickness (r s ϭϪ0.61; Pϭ0.01), and increasing degrees of stenosis (r s ϭ0.71; Pϭ0.003). Peak stress levels were asymmetrically distributed longitudinally, with 50% occurring proximal to the maximal stenosis, 25% at the point of maximal stenosis, and 25% distal to the maximal stenosis. Conclusion-The peak longitudinal mechanical stresses in the fibrous caps of symptomatic patients with carotid atherosclerotic stenosis were located at known predilection sites for plaque rupture, suggesting that mechanical stresses may play a role in plaque destabilization.

show abstract

“…A 3-D FSI model has revealed an association between regions of high plaque critical stress and fibrous cap disruption in human carotid plaques. 50 Furthermore, maximum principal stresses were identified on shoulder regions of the fibrous caps of carotid plaques, according to the simulations of Kock et al 151 A histology-based finite element analysis was used by Vengrenyuk et al 152 to investigate the peak circumferential stresses in aortic and brachiocephalic plaques of ApoE-/-mice. Both peak and circumferential stresses in the aortic lesions were found to be significantly less than in the brachiocephalic lesions, despite only modestly larger cap thickness.…”

Section: Plaque Rupture Structural Stressmentioning

confidence: 99%

Evolution and rupture of vulnerable plaques: a review of mechanical effects

Assemat¹,

Hourigan²

2013

CPT

View full text Add to dashboard Cite

Atherosclerosis occurs as a result of the buildup and infiltration of lipid streaks in artery walls, leading to plaques. Understanding the development of atherosclerosis and plaque vulnerability is of critical importance, since plaque rupture can result in heart attack or stroke. Plaques can be divided into two distinct types: those that rupture (vulnerable) and those that are less likely to rupture (stable). In the last few decades, researchers have been interested in studying the influence of the mechanical effects (blood shear stress, pressure forces, and structural stress) on the plaque formation and rupture processes. In the literature, physiological experimental studies are limited by the complexity of in vivo experiments to study such effects, whereas the numerical approach often uses simplified models compared with realistic conditions, so that no general agreement of the mechanisms responsible for plaque formation has yet been reached. In addition, in a large number of cases, the presence of plaques in arteries is asymptomatic. The prediction of plaque rupture remains a complex question to elucidate, not only because of the interaction of numerous phenomena involved in this process (biological, chemical, and mechanical) but also because of the large time scale on which plaques develop. The purpose of the present article is to review the current mechanical models used to describe the blood flow in arteries in the presence of plaques, as well as reviewing the literature treating the influence of mechanical effects on plaque formation, development, and rupture. Finally, some directions of research, including those being undertaken by the authors, are described.

show abstract

Mechanical stresses in carotid plaques using MRI-based fluid–structure interaction models

Cited by 116 publications

References 49 publications

The Effect of Carotid Plaque Morphology on Longitudinal Fibrous Cap Stress Levels

The Effect of Carotid Plaque Morphology on Longitudinal Fibrous Cap Stress Levels

Longitudinal Distribution of Mechanical Stresses in Carotid Plaques of Symptomatic Patients

Evolution and rupture of vulnerable plaques: a review of mechanical effects

Contact Info

Product

Resources

About