Eventos Anais de eventos
COBEM 2023
27th International Congress of Mechanical Engineering
Analysis on the effect of connecting links in the foreshortening of a bioabsorbable stent for the treatment of Aorta Coarctation in Children: a Finite element study
Submission Author:
Flávio Santos , SP
Co-Authors:
Flávio Santos, Bruno Agostinho Hernandez, Marcel Machado, ROSANA SANTOS, Aron Andrade, EDSON CAPELLO SOUSA
Presenter: Bruno Agostinho Hernandez
doi://10.26678/ABCM.COBEM2023.COB2023-0379
Abstract
Coarctation of the Aorta (CoA) is a congenital heart disease that causes a narrowing of the aorta artery cross-section area, partially reducing the blood flow. Some studies estimated about 51,000 new-borns per year worldwide have some degree of CoA. One of the most traditional treatments for CoA is the use of metallic stents. However, their use in young children is limited due to the patient’s constant growth and the need for new surgeries for stent expansion; which is only possible up to a certain diameter. Limited foreshortening is one of the key features of a stent during CoA treatment. Thus, the development of a bioabsorbable stent was idealised, as these devices degrade over time and remain temporarily in the patient's body; an ideal scenario for children. The finite element method is widely used in the development of biomechanical devices and this study aimed to evaluate the influence of the connecting links in the bioabsorbable stent performance in terms of foreshortening for the treatment of Aorta Coarctation in Children. Three different types of connecting links were analysed: beam, bracket, and braces. All geometries had an outer diameter of 6.75 mm, a wall thickness of 0.25 mm, and they were modelled in CAD software. During the simulations at ANSYS software, a surface-type balloon was used to expand the geometries until reaching a varied maximum diameter ranging from 11 to 15 mm. It was found that the type of connecting links highly impacted the foreshortening performance during the expansion of the stent, as the geometry with braces’ connecting links elongated instead of shortening, as occurred with the other two geometries. The developed model allowed a simulation of the structural behaviour of three new geometries of bioabsorbable stents for the treatment of aorta coarctation. An evaluation of the stent's performance in terms of foreshortening during its implantation as well as the influence of the type of connecting link was assessed.
Keywords
Coarctation of the Aorta (CoA), Finite Element Method, Foreshortening, Bioabsorbable Stents
