Finite element shape optimization for biodegradable magnesium alloy stents

W. Wu, L. Petrini, D. Gastaldi, T. Villa, M. Vedani, E. Lesma, B. Previtali, F. Migliavacca

Research output: Contribution to journalArticle

74 Citations (Scopus)

Abstract

Biodegradable magnesium alloy stents (MAS) are a promising solution for long-term adverse events caused by interactions between vessels and permanent stent platforms of drug eluting stents. However, the existing MAS showed severe lumen loss after a few months: too short degradation time may be the main reason for this drawback. In this study, a new design concept of MAS was proposed and a shape optimization method with finite element analysis was applied on two-dimensional (2D) stent models considering four different magnesium alloys: AZ80, AZ31, ZM21, and WE43. A morphing procedure was utilized to facilitate the optimization. Two experiments were carried out for a preliminary validation of the 2D models with good results. The optimized designs were compared to an existing MAS by means of three-dimensional finite element analysis. The results showed that the final optimized design with alloy WE43, compared to the existing MAS, has an increased strut width by approximately 48%, improved safety properties (decreased the maximum principal stress after recoil with tissue by 29%, and decreased the maximum principal strain during expansion by 14%) and improved scaffolding ability (increased by 24%). Accordingly, the degradation time can be expected to extend. The used methodology provides a convenient and practical way to develop novel MAS designs.

Original languageEnglish
Pages (from-to)2829-2840
Number of pages12
JournalAnnals of Biomedical Engineering
Volume38
Issue number9
DOIs
Publication statusPublished - Sep 2010

Fingerprint

Stents
Shape optimization
Magnesium alloys
Finite element method
Degradation
Struts
Tissue

Keywords

  • Bioabsorbable device
  • Computational analysis
  • Experimental tests
  • Minimally invasive device
  • Optimized design

ASJC Scopus subject areas

  • Biomedical Engineering

Cite this

Wu, W., Petrini, L., Gastaldi, D., Villa, T., Vedani, M., Lesma, E., ... Migliavacca, F. (2010). Finite element shape optimization for biodegradable magnesium alloy stents. Annals of Biomedical Engineering, 38(9), 2829-2840. https://doi.org/10.1007/s10439-010-0057-8

Finite element shape optimization for biodegradable magnesium alloy stents. / Wu, W.; Petrini, L.; Gastaldi, D.; Villa, T.; Vedani, M.; Lesma, E.; Previtali, B.; Migliavacca, F.

In: Annals of Biomedical Engineering, Vol. 38, No. 9, 09.2010, p. 2829-2840.

Research output: Contribution to journalArticle

Wu, W, Petrini, L, Gastaldi, D, Villa, T, Vedani, M, Lesma, E, Previtali, B & Migliavacca, F 2010, 'Finite element shape optimization for biodegradable magnesium alloy stents', Annals of Biomedical Engineering, vol. 38, no. 9, pp. 2829-2840. https://doi.org/10.1007/s10439-010-0057-8
Wu, W. ; Petrini, L. ; Gastaldi, D. ; Villa, T. ; Vedani, M. ; Lesma, E. ; Previtali, B. ; Migliavacca, F. / Finite element shape optimization for biodegradable magnesium alloy stents. In: Annals of Biomedical Engineering. 2010 ; Vol. 38, No. 9. pp. 2829-2840.
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