Experimentally validated simulation of coronary stents considering different dogboning ratios and asymmetric stent positioning

PLoS One. 2019 Oct 18;14(10):e0224026. doi: 10.1371/journal.pone.0224026. eCollection 2019.

Abstract

In-stent restenosis remains a major problem of arteriosclerosis treatment by stenting. Expansion-optimized stents could reduce this problem. With numerical simulations, stent designs/ expansion behaviours can be effectively analyzed. For reasons of efficiency, simplified models of balloon-expandable stents are often used, but their accuracy must be challenged due to insufficient experimental validation. In this work, a realistic stent life-cycle simulation has been performed including balloon folding, stent crimping and free expansion of the balloon-stent-system. The successful simulation and validation of two stent designs with homogenous and heterogeneous stent stiffness and an asymmetrically positioned stent on the balloon catheter confirm the universal applicability of the simulation approach. Dogboning ratio, as well as the final dimensions of the folded balloon, the crimped and expanded stent, correspond well to the experimental dimensions with only slight deviations. In contrast to the detailed stent life-cycle simulation, a displacement-controlled simulation can not predict the transient stent expansion, but is suitable to reproduce the final expanded stent shape and the associated stress states. The detailed stent life-cycle simulation is thus essential for stent expansion analysis/optimization, whereas for reasons of computational efficiency, the displacement-controlled approach can be considered in the context of pure stress analysis.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Angioplasty, Balloon, Coronary
  • Arteriosclerosis / therapy
  • Computer Simulation
  • Humans
  • Models, Cardiovascular
  • Prosthesis Design*
  • Stents*

Grants and funding

This work was supported by the Bavarian State Ministry for Education, Culture, Science and Arts, Project “OptiStent” under grant No. AZ VIII.2-F1116.RE/17/3. This work was further supported by the by the Bavarian Academic Forum (BayWISS) – Doctoral Consortium “Health Research”, also funded by the Bavarian State Ministry of Science and Arts. LW was further supported by a scholarship of the LaKoF (State Conference of Women’s and Equal Opportunities Representatives at Bavarian Universities). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.