The impact of strut profile geometry and malapposition on the haemodynamics and drug-transport behaviour of arteries treated with drug-eluting stents
International Journal of Numerical Methods for Heat & Fluid Flow
ISSN: 0961-5539
Article publication date: 24 May 2022
Issue publication date: 25 November 2022
Abstract
Purpose
Stent malapposition is one of the most significant precursors of stent thrombosis and restenosis. Adverse haemodynamics may play a key role in establishing these diseases, although numerical studies have used idealised drug transport models to show that drug transport from malapposed drug-eluting stent struts can be significant. This paper aims to study whether drug transport from malapposed struts is truly significant. Another aim is to see whether a streamlined strut profile geometry – with a 61% smaller coating but a 32% greater coating-tissue contact area – can mitigate the adverse haemodynamics associated with stent malapposition while enhancing drug uptake.
Design/methodology/approach
Two- and three-dimensional computational fluid dynamics simulations were used in this study. Unlike past simulations of malapposed drug-eluting stent struts, a qualitatively validated drug-transport model which simulates the non-uniform depletion of drug within the drug coating was implemented.
Findings
It was shown that even a 10-µm gap between the strut and tissue dramatically reduces drug uptake after 24 h of simulated drug transport. Furthermore, the streamlined strut profile was shown to minimise the adverse haemodynamics of malapposed and well-apposed stent struts alike and enhance drug uptake.
Originality/value
Unlike prior numerical studies of malapposed stent struts, which did not model the depletion of drug in the drug coating, it was found that stent malapposition yields negligible drug uptake. The proposed semicircular-profiled strut was also shown to be advantageous from a haemodynamic and drug transport perspective.
Keywords
Acknowledgements
This study was supported by the Australian Postgraduate Award Scheme. This support did not otherwise influence the writing of this article.
Ethics statement: This is a numerical study using idealised geometries and, as such, no ethics approval was required.
Citation
Vijayaratnam, P.R.S., Reizes, J.A. and Barber, T.J. (2022), "The impact of strut profile geometry and malapposition on the haemodynamics and drug-transport behaviour of arteries treated with drug-eluting stents", International Journal of Numerical Methods for Heat & Fluid Flow, Vol. 32 No. 12, pp. 3881-3907. https://doi.org/10.1108/HFF-03-2022-0145
Publisher
:Emerald Publishing Limited
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