RESUMO
PURPOSE: As the promoter of the stent expansion, the balloon plays a very important role, offering a strong influence on the deployment process. Balloon-artery interaction is pointed as a probable cause of restenosis, stressing the relevance of balloon modeling when simulating the stenting procedure. In this work, an in-silico study of the balloon modeling strategies is performed. METHODS: Ultrasonic-microcasting is a novel technology that allows obtaining stents manufactured in magnesium alloys, being suggested as a promising solution. However, this technique demands superior stent strut thickness, which may have an impact on the stent deployment procedure. The influence of the balloon modeling is studied through the simulation of different balloon geometries (open- or taper-ended) and material constitutive model (linear elastic or hyperelastic) on the expanded configuration of a stent manufactured through ultrasonic-microcasting. RESULTS: The results obtained suggest that the choice of balloon type has small impact in terms of demanded pressure to inflate the balloon and in the stent final radius achieved at fully-expanded configuration. Additionally, it was proved that the balloon-type influences the stent expanded profile along its length and diameter as a result of the different deformation behavior exhibited by the balloon. CONCLUSION: The hyperelastic taper-ended balloon suggests being the model that better correlates with both experimental and clinical results regarding the expanded balloon profile during the procedure.
