Subjective approach to optimal cross-sectional design of biodegradable magnesium alloy stent undergoing heterogeneous corrosion

Najmeh Zarei; Seyed Ahmad Anvar; Sevan Goenezen

doi:10.14311/AP.2021.61.0661

Authors

Najmeh Zarei Shiraz University, Department of Civil and Environmental Engineering, Shiraz 71348, Iran
Seyed Ahmad Anvar Shiraz University, Department of Civil and Environmental Engineering, Shiraz 71348, Iran
Sevan Goenezen Texas A & M University, Department of Mechanical Engineering, College Station, 77843 Texas, USA

DOI:

https://doi.org/10.14311/AP.2021.61.0661

Keywords:

coronary stent, biodegradation, magnesium, pitting corrosion, finite element

Abstract

Existing biodegradable Magnesium Alloy Stents (MAS) have several drawbacks, such as high restenosis, hasty degradation, and bulky cross-section, that limit their widespread application in a current clinical practice. To find the optimum stent with the smallest possible cross-section and adequate scaffolding ability, a 3D finite element model of 25 MAS stents of different cross-sectional dimensions were analysed while localized corrosion was underway. For the stent geometric design, a generic sine-wave ring of biodegradable magnesium alloy (AZ31) was selected. Previous studies have shown that the long-term performance of MAS was characterized by two key features: Stent Recoil Percent (SRP) and Stent Radial Stiffness (SRS). In this research, the variation with time of these two features during the corrosion phase was monitored for the 25 stents. To find the optimum profile design of the stent subjectively (without using optimization codes and with much less computational costs), radial recoil was limited to 27 % (corresponding to about 10 % probability of in-stent diameter stenosis after an almost complete degradation) and the stent with the highest radial stiffness was selected.
The comparison of the recoil performance of 25 stents during the heterogeneous corrosion phase showed that four stents would satisfy the recoil criterion and among these four, the one having a width of 0.161 mm and a thickness of 0.110 mm, showed a 24 % – 49 % higher radial stiffness at the end of the corrosion phase. Accordingly, this stent, which also showed a 23.28 % mass loss, was selected as the optimum choice and it has a thinner cross-sectional profile than commercially available MAS, which leads to a greater deliverability and lower rates of restenosis.

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References

R. Erbel, C. Di Mario, J. Bartunek, et al. Temporary scaffolding of coronary arteries with bioabsorbable magnesium stents: a prospective, non-randomised multicentre trial. The Lancet 369(9576):1869–1875, 2007. https://doi.org/10.1016/s0145-4145(08)04009-4.

M. Haude, R. Erbel, P. Erne, et al. Safety and performance of the drug-eluting absorbable metal scaffold (DREAMS) in patients with de-novo coronary lesions: 12 month results of the prospective, multicentre, first-in-man BIOSOLVE-I trial. The Lancet 381(9869):836–844, 2013. https://doi.org/10.1016/s0140-6736(12)61765-6.

B. D. Gogas. Bioresorbable scaffolds for percutaneous coronary interventions. Global Cardiology Science and Practice 2014(4), 2015. https://doi.org/10.5339/gcsp.2014.55.

P. E. McHugh, J. A. Grogan, C. Conway, E. Boland. Computational modeling for analysis and design of metallic biodegradable stents. Journal of Medical Devices 9(3):030946, 2015. https://doi.org/10.1115/1.4030576.

T. Hu, C. Yang, S. Lin, et al. Biodegradable stents for coronary artery disease treatment: Recent advances and future perspectives. Materials Science and Engineering: C 91:163–178, 2018. https://doi.org/10.1016/j.msec.2018.04.100.

D. Gastaldi, V. Sassi, L. Petrini, et al. Continuum damage model for bioresorbable magnesium alloy devices — application to coronary stents. Journal of the Mechanical Behavior of Biomedical Materials 4(3):352–365, 2011. https://doi.org/10.1016/j.jmbbm.2010.11.003.

W. Wu, S. Chen, D. Gastaldi, et al. Experimental data confirm numerical modeling of the degradation process of magnesium alloys stents. Acta Biomaterialia 9(10):8730–8739, 2013. https://doi.org/10.1016/j.actbio.2012.10.035.

W. Wu, D. Gastaldi, K. Yang, et al. Finite element analyses for design evaluation of biodegradable magnesium alloy stents in arterial vessels. Materials Science and Engineering: B 176(20):1733–1740, 2011. https://doi.org/10.1016/j.mseb.2011.03.013.

J. A. Grogan, B. J. O’Brien, S. B. Leen, et al. A corrosion model for bioabsorbable metallic stents. Acta Biomaterialia 7(9):3523–3533, 2011. https://doi.org/10.1016/j.actbio.2011.05.032.

W. Wu, L. Petrini, D. Gastaldi, et al. Finite element shape optimization for biodegradable magnesium alloy stents. Annals of Biomedical Engineering 38(9):2829–2840, 2010. https://doi.org/10.1007/s10439-010-0057-8.

J. A. Grogan, S. B. Leen, P. E. McHugh. Optimizing the design of a bioabsorbable metal stent using computer simulation methods. Biomaterials 34(33):8049–8060, 2013. https://doi.org/10.1016/j.biomaterials.2013.07.010.

C. Chen, J. Chen, W. Wu, et al. In vivo and in vitro evaluation of a biodegradable magnesium vascular stent designed by shape optimization strategy. Biomaterials 221:119414, 2019. https://doi.org/10.1016/j.biomaterials.2019.119414.

X. Ni, Y. Zhang, C. Pan. The degradable performance of bile-duct stent based on a continuum damage model: A finite element analysis. International Journal for Numerical Methods in Biomedical Engineering p. 36:e3370, 2020. https://doi.org/10.1002/cnm.3370.

L. Petrini, F. Migliavacca, F. Auricchio, et al. Numerical investigation of the intravascular coronary stent flexibility. Journal of Biomechanics 37(4):495–501, 2004. https://doi.org/10.1016/j.jbiomech.2003.09.002.

S. Pant, N. W. Bressloff, G. Limbert. Geometry parameterization and multidisciplinary constrained optimization of coronary stents. Biomechanics and Modeling in Mechanobiology 11(1-2):61–82, 2012. https://doi.org/10.1007/s10237-011-0293-3.

H. Li, J. Gu, M. Wang, et al. Multi-objective optimization of coronary stent using Kriging surrogate model. BioMedical Engineering OnLine 15:148, 2016. https://doi.org/10.1186/s12938-016-0268-9.

C. McCormick. Overview of cardiovascular stent designs. In Functionalised Cardiovascular Stents, pp. 3–26. Woodhead Publishing, 2018. https://doi.org/10.1016/b978-0-08-100496-8.00001-9.

M. De Beule, S. Van Cauter, P. Mortier, et al. Virtual optimization of self-expandable braided wire stents. Medical Engineering & Physics 31(4):448–453, 2009. https://doi.org/10.1016/j.medengphy.2008.11.008.

M. De Beule, P. Mortier, S. G. Carlier, et al. Realistic finite element-based stent design: the impact of balloon folding. Journal of Biomechanics 41(2):383–389, 2008. https://doi.org/10.1016/j.jbiomech.2007.08.014.

F. Gervaso, C. Capelli, L. Petrini, et al. On the effects of different strategies in modelling balloonexpandable stenting by means of finite element method. Journal of Biomechanics 41(6):1206–1212, 2008. https://doi.org/10.1016/j.jbiomech.2008.01.027.

R. Waksman. Current state of the absorbable metallic (magnesium) stent. Euro Intervention: Journal of EuroPCR in Collaboration with the Working Group on Interventional Cardiology of the European Society of Cardiology 5:F94–F97, 2009. https://doi.org/10.4244/eijv5ifa16.

R. Waksman, R. Erbel, C. Di Mario, et al. Early-and long-term intravascular ultrasound and angiographic findings after bioabsorbable magnesium stent implantation in human coronary arteries. JACC: Cardiovascular Interventions 2(4):312–320, 2009. https://doi.org/10.1016/j.jcin.2008.09.015.