TY - JOUR
T1 - Effects of material, coating, design and plaque composition on stent deployment inside a stenotic artery - Finite element simulation
AU - Schiavone, A.
AU - Zhao, L.G.
AU - Abdel-Wahab, A.A.
PY - 2014/9/1
Y1 - 2014/9/1
N2 - Finite-element simulations have been carried out to study the effects of material choice, drug eluting coating and cell design on the mechanical behaviour of stents during deployment inside a stenotic artery. Metallic stents made of materials with lower yield stress and weaker strain hardening tend to experience higher deformation and stronger dogboning and recoiling, but less residual stresses. Drug eluting coatings have limited effect on stent expansion, recoiling, dogboning and residual stresses. Stent expansion is mainly controlled by the radial stiffness of the stent which is closely associated with the stent design. In particular, open-cell design tends to have easier expansion and higher recoiling than closed-cell design. Dogboning is stronger for slotted tube design and open-cell sinusoidal design, but reduced significantly for designs strengthened with longitudinal connective struts. After deployment, the maximum von Mises stress appears to locate at the U-bends of stent cell struts, with varying magnitude that depends on the materials and severity of plastic deformation. For the artery–plaque system, the stresses, especially in the plaque which is in direct contact with the stent, appear to be distinctly different for different stent designs and materials in terms of both distribution and magnitude. The plaque composition also strongly affects the expansion behaviour of the stent–artery system and modifies the stresses on the plaque.
AB - Finite-element simulations have been carried out to study the effects of material choice, drug eluting coating and cell design on the mechanical behaviour of stents during deployment inside a stenotic artery. Metallic stents made of materials with lower yield stress and weaker strain hardening tend to experience higher deformation and stronger dogboning and recoiling, but less residual stresses. Drug eluting coatings have limited effect on stent expansion, recoiling, dogboning and residual stresses. Stent expansion is mainly controlled by the radial stiffness of the stent which is closely associated with the stent design. In particular, open-cell design tends to have easier expansion and higher recoiling than closed-cell design. Dogboning is stronger for slotted tube design and open-cell sinusoidal design, but reduced significantly for designs strengthened with longitudinal connective struts. After deployment, the maximum von Mises stress appears to locate at the U-bends of stent cell struts, with varying magnitude that depends on the materials and severity of plastic deformation. For the artery–plaque system, the stresses, especially in the plaque which is in direct contact with the stent, appear to be distinctly different for different stent designs and materials in terms of both distribution and magnitude. The plaque composition also strongly affects the expansion behaviour of the stent–artery system and modifies the stresses on the plaque.
KW - Stent expansion
KW - Stenotic artery
KW - Finite element
KW - Recoiling
KW - Dogboning
KW - Stresses
UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84903215811&partnerID=MN8TOARS
U2 - 10.1016/j.msec.2014.05.057
DO - 10.1016/j.msec.2014.05.057
M3 - Article
SN - 0928-4931
VL - 42
SP - 479
EP - 488
JO - Materials Science and Engineering C
JF - Materials Science and Engineering C
ER -