Realistic finite element-based stent design: the impact of balloon folding.

The influence of plaque composition on underlying arterial wall stress during stent expansion: The case for lesion-specific stents

On the effects of different strategies in modelling balloon-expandable stenting by means of finite element method.

The process of restenosis after a stenting procedure is related to local biomechanical environment. Arterial wall stresses caused by the interaction of the stent with the vascular wall and possibly stress induced stent strut fracture are two important parameters. The knowledge of these parameters after stent deployment in a patient derived 3D reconstruction of a diseased coronary artery might give insights in the understanding of the process of restenosis. 3D reconstruction of a mildly stenosed coronary artery was carried out based on a combination of biplane angiography and intravascular ultrasound. Finite element method computations were performed to simulate the deployment of a stent inside the reconstructed coronary artery model at inflation pressure of 1.0 MPa. Strut thickness of the stent was varied to investigate stresses in the stent and the vessel wall. Deformed configurations, pressure-lumen area relationship and stress distribution in the arterial wall and stent struts were studied. The simulations show how the stent pushes the arterial wall towards the outside allowing the expansion of the occluded artery. Higher stresses in the arterial wall are present behind the stent struts and in regions where the arterial wall was thin. Values of 200 MPa for the peak stresses in the stent strut were detected near the connecting parts between the stent struts, and they were only just below the fatigue stress. Decreasing strut thickness might reduce arterial damage without increasing stresses in the struts significantly. The method presented in this paper can be used to predict stresses in the stent struts and the vessel wall, and thus evaluate whether a specific stent design is optimal for a specific patient.

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Simulation of stent deployment in a realistic human coronary artery

Stent expansion in curved vessel and their interactions: a finite element analysis.

Analysis of the transient expansion behavior and design optimization of coronary stents by finite element method

Finite element analysis of the implantation of a balloon-expandable stent in a stenosed artery.

Instent restenosis (ISR) has been a key factor that restricts the further use of intraoronary stents. And the mechanical interaction between the stent and the artery has been indicated as one of the significant causes for the activation of stent-related restenosis. However, there is very little quantitative information about the interaction of stent with artery. In order to improve the general understanding of coronary stenting, finite element method (FEM) has been used to model the revascularization of a stenosed artery through the insertion of a balloon-expandable stent. Given a stent design, the deformed shape of the stent and possible areas of the artery injury were presented. The fact that the distal end of stent penetrated into the artery wall may help to explain the phenomena that much restenosis occurs at the ends of stents. The recoil ratios of the stent model, the plaque-artery model and the stent-plaque-artery model were 2%, 26.7% and11.3%, respectively. They were well consistent with the experimental data. In conclusion, this work would be helpful for the general understanding of intraoronary stent implantation and stent design optimization.

Finite Element Analysis of a Stent Implantation in a Stenosed Artery

The utility model discloses a nickel titanium alloy support in medical field, the laser curved 'quasi sine' tube type nickel titanium alloy support is a pipe network structure made of many groups the 'quasi sine' corrugated ring which is enchased by the nitinol and presents the pairwise mirror symmetry. The laser curved 'quasi sine' tube type nickel titanium alloy support is can be used in the lumen for the carotid, the biliary passage, the esophagus, etc. vessels. The utility model is characterized in that the support can expand of itself by using the super elasticity of the niti-shaped memorial alloy, and does not need the saccule. The centre shaft is arranged towards to the adjacent 'quasi sine' corrugated ring and presents the mirror symmetry, and two ends of the centre shaft are designed as a bell mouth shape; the corrugated ring of the end part is longer than the corrugated ring of the case body. The wave crest of the relative elements are connected together by a short straight splice bar, one wave crest is arraned between the splice bars at the ends, and the two wave crests are positioned between the splice bars at the case body. The shape of the wave crest at outside of the bell mouth on the end is different from the shape of the other regions, and the top of the wave crest at the other regions are presented a ring type.

Dongke Liang

Papers

Analysis of the transient expansion behavior and design optimization of coronary stents by finite element method

Finite element analysis of the implantation of a balloon-expandable stent in a stenosed artery.

Finite Element Analysis of a Stent Implantation in a Stenosed Artery

Laser curved 'quasi sine' tube type nickel titanium alloy support

Finite element method and computational fluid dynamics used in the analysis of a stent