A computational study of the effect of stent design on local hemodynamic factors at the carotid artery bifurcation
File(s)
Published version
Author(s)
Johari, Nasrul Hadi
Hamady, Mohamad
Xu, Xiao Yun
Type
Journal Article
Abstract
Background: Previous clinical studies have shown that the incidence of restenosis after carotid and coronary stenting varies with stent design and deployment configuration. This study aims to determine how stent design may affect in-stent hemodynamics in stented carotid arteries by means of Computational Fluid Dynamics (CFD).
Methods: A robust computational method was developed to integrate detailed stent strut geometry in a patient-specific carotid artery reconstructed from medical images. Three stent designs, including two closed-cell stents and one open-cell stent, were reproduced and incorporated into the reconstructed post-stent carotid bifurcation. CFD simulations were performed under patient-specific flow conditions. Local hemodynamic parameters were evaluated and compared in terms of Wall Shear Stress (WSS), Oscillatory Shear Index (OSI) and Relative Residence Time (RRT).
Results: All simulated stent designs induced some degree of flow disruption as manifested through flow separation and recirculation zones downstream of stent struts and quantified by WSS-related indices. Compared to the simulated open-cell stent, closed-cell stents created slightly larger areas of low WSS, elevated OSI and high RRT, due to a greater number of stent struts protruding into the lumen.
Conclusion: Detailed stent design and patient-specific geometric features of the stented vessel have a strong influence on the evaluated hemodynamic parameters. Our limited computational results suggest that closed-cell stents may pose a higher risk for in-stent restenosis (ISR) than open-cell stent design. Further large-scale prospective studies are warranted to elucidate the role of stent design in the development of ISR after CAS.
Methods: A robust computational method was developed to integrate detailed stent strut geometry in a patient-specific carotid artery reconstructed from medical images. Three stent designs, including two closed-cell stents and one open-cell stent, were reproduced and incorporated into the reconstructed post-stent carotid bifurcation. CFD simulations were performed under patient-specific flow conditions. Local hemodynamic parameters were evaluated and compared in terms of Wall Shear Stress (WSS), Oscillatory Shear Index (OSI) and Relative Residence Time (RRT).
Results: All simulated stent designs induced some degree of flow disruption as manifested through flow separation and recirculation zones downstream of stent struts and quantified by WSS-related indices. Compared to the simulated open-cell stent, closed-cell stents created slightly larger areas of low WSS, elevated OSI and high RRT, due to a greater number of stent struts protruding into the lumen.
Conclusion: Detailed stent design and patient-specific geometric features of the stented vessel have a strong influence on the evaluated hemodynamic parameters. Our limited computational results suggest that closed-cell stents may pose a higher risk for in-stent restenosis (ISR) than open-cell stent design. Further large-scale prospective studies are warranted to elucidate the role of stent design in the development of ISR after CAS.
Date Issued
2020-09
Date Acceptance
2020-05-27
Citation
Artery Research, 2020, 26 (3), pp.161-169
ISSN
1872-9312
Publisher
Elsevier
Start Page
161
End Page
169
Journal / Book Title
Artery Research
Volume
26
Issue
3
Copyright Statement
© 2020 Association for Research into Arterial Structure and Physiology. Publishing services by Atlantis Press International B.V. This is an open access article distributed under the CC BY-NC 4.0 license (http://creativecommons.org/licenses/by-nc/4.0/).
License URL
Identifier
https://www.atlantis-press.com/journals/artres/125941082
Subjects
Science & Technology
Life Sciences & Biomedicine
Peripheral Vascular Disease
Cardiovascular System & Cardiology
Carotid artery stenting
hemodynamics
in stent restenosis
computational fluid dynamics
FLUID-STRUCTURE INTERACTION
CLOSED-CELL STENTS
WALL SHEAR-STRESS
ENDARTERECTOMY
RESTENOSIS
STENOSIS
STROKE
ATHEROSCLEROSIS
PREVENTION
VELOCITIES
Cardiovascular System & Hematology
1103 Clinical Sciences
Publication Status
Published
Date Publish Online
2020-06-07