journal article

Journal Article

Text

International Journal for Numerical Methods in Biomedical Engineering. 2021, 37(12), p. e3335

Computational modeling of braided-stent deployment for interpreting the mechanism of stent flattening

John Wiley and Sons

English

Text

2021-12

https://doi.org/10.1002/cnm.3335

This is the peer reviewed version of the following article: Shiozaki, S, Otani, T, Fujimura, S, Takao, H, Wada, S. Computational modeling of braided-stent deployment for interpreting the mechanism of stent flattening. Int J Numer Meth Biomed Engng. 2021; 37:e3335., which has been published in final form at https://doi.org/10.1002/cnm.3335. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving. This article may not be enhanced, enriched or otherwise transformed into a derivative work, without express permission from Wiley or by statutory rights under applicable legislation. Copyright notices must not be removed, obscured or modified. The article must be linked to Wiley’s version of record on Wiley Online Library and any embedding, framing or otherwise making available the article or pages thereof by third parties from platforms, services and websites other than Wiley Online Library must be prohibited.

This study develops a computational model of the braided stent for interpreting the mechanism of stent flattening during deployment into curved arteries. Stent wires are expressed using Kirchhoff's rod theory and their mechanical behavior is treated using a corotational beam formulation. The equation of motion of the braided stent is solved in a step-by-step manner using the resultant elastic force and mechanical interactions of wires with friction. Examples of braided-stent deployment into idealized arteries with various curvatures are numerically simulated. In cases of low curvature, the braided stent expands from a catheter by releasing the bending energy stored in stent wires, while incomplete expansion is found at both stent ends (ie, the fish-mouth phenomenon), where relatively little bending energy is stored. In cases of high curvature, much torsional energy is stored in stent wires locally in the midsection of the curvature and the bending energy for stent self-expansion is not fully released even after deployment, leading to stent flattening. These findings suggest that the mechanical state of the braided stent and its transition during deployment play an important role in the underlying mechanism of stent flattening. Novelty Statement: This study developed a computational mechanical model of the braided stent for interpreting stent flattening, which is a critical issue observed during deployment into highly curved arteries. Mechanical behaviors of the stent wires are appropriately treated by corotational beam element formulation with considering multiple contacts. We conducted numerical examples of the stent deployment into curved arteries and found that the mechanical state of the braided stent during deployment associated with occurrences of the stent flattening. We believe this finding gives new insight into the mechanism of stent flattening and would advance the design of the stent and its deployment protocol.

© 2020 John Wiley & Sons, Ltd.

88324

Computational modeling of braided-stent deployment for interpreting the mechanism of stent flattening

John Wiley and Sons

English

2021-12

International Journal for Numerical Methods in Biomedical Engineering

37

12

e3335

https://doi.org/10.1002/cnm.3335

32212324

https://hdl.handle.net/11094/88324