Thoracic aortic parallel stent-graft behaviour when subjected to radial loading. (June 2021)

• Record Type: Journal Article
• Authors: Kwiecinski, Jakub; Cheng, Christopher P.; Uberoi, Raman; Hadi, Mohammed; Hempel, Philipp; Degel, Christoph; You, Zhong
• Is Part Of: Journal of the mechanical behavior of biomedical materials. Volume 118(2021)
• Publication Date: 2021-06
• Subjects: Stent-graft -- Chimney graft -- Parallel graft -- Endograft -- Gutter -- Endoleak -- Radial force -- Thoracic aortic aneurysm -- Dissection -- Endovascular repair -- TEVAR -- Nitinol -- Stent testing; Biomedical materials -- Periodicals; Biomedical materials -- Mechanical properties -- Periodicals; Biomedical materials; Biomedical materials -- Mechanical properties; Periodicals; Electronic journals; 610.28
• DOI: 10.1016/j.jmbbm.2021.104407
• Languages: English
• ISSNs: 1751-6161

Abstract

Abstract: To manage complex aortic arch disease using minimally invasive techniques, interventionalists have reported the use of multiple stent-graft devices deployed in a parallel configuration. The structural device-device and device-artery interactions arising during aortic arch parallel endografting, also known as chimney thoracic endovascular aortic repair (ch-TEVAR), is not well understood. Through the use of a radial force testing system we sought to characterise both the loading and deformation behaviour of parallel endografts in representative ch-TEVAR configurations. Four commercially available devices (Bentley BeGraft, Gore TAG, Gore Viabahn, and Medtronic Valiant) were subjected to uniform radial load individually, and in six combinations, to quantify loading profiles. Image data collected during testing were analysed to evaluate mechanical deformations in terms of gutters, chimney and main endograft compression, as well as graft infolding. Parallel endografting was found to increase radial loads when compared to standard TEVAR. Chronic outward force during ch-TEVAR was dependent on main endograft manufacturer, with TAG combinations leading to consistently higher loads than Valiant, but independent of chimney graft type. Endograft deformations were dependent on chimney graft type, with Viabahn combinations presenting with lower gutter areas and increased lumen compression than BeGraft. Chimney graft deformations were also influenced by deployment arrangement in the case of double ch-TEVAR. This study emphasizes the significant variability in both radial loads and mechanical deformations between clinically relevant ch-TEVAR configurations. Graphical abstract: Image 1 Highlights: The mechanics of stent-graft devices when deployed in a parallel configuration is not well understood. Radial loading and deformation behaviour of six clinically relevant parallel endograft configurations have been assessed. Parallel endografting may result in increased aortic wall loading in vivo . Mechanical deformations are dependent on device type and deployed arrangement.