Article

Computational fluid dynamics and stent design.

Biomedical Engineering Institute, Florida International University, Miami, Florida, USA.
Artificial Organs (impact factor: 2). 08/2002; 26(7):614-21. pp.614-21
Source: PubMed

ABSTRACT Stents are small, usually metallic tubes that are intended to prop open arteries blocked with atherosclerotic plaques. While stents have been used successfully in recent years, they still suffer from failure due to development of new tissue in stented segment (restenosis). Variations in the failure rates associated with different stent designs have led researchers to investigate the role of near-wall flow patterns. While there is no direct evidence yet, the patterns of flow stagnation as the blood flows past the stent struts may affect the restenosis process. Computational fluid dynamics (CFD) approaches are well suited for obtaining detailed information on stent flow patterns. Many CFD simulations make use of a two-dimensional model. The strong dependence of flow stagnation on stent strut spacing has been clearly demonstrated. These results have been employed to interpret the results of in vitro experiments designed to elucidate the mechanisms of restenosis.

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Keywords

atherosclerotic plaques
 
blood flows
 
CFD simulations
 
Computational fluid dynamics
 
different stent designs
 
direct evidence
 
failure rates
 
flow stagnation
 
near-wall flow patterns
 
new tissue
 
open arteries
 
researchers
 
stent flow patterns
 
stent strut spacing
 
stent struts
 
stented segment
 
Stents
 
strong dependence
 
two-dimensional model
 
Variations
 

Andreas O Frank