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Redo-transcatheter aortic valve implantation (redo-TAVI) is an emerging solution for failed transcatheter heart valves (THVs) in patients with aortic stenosis who outlive their initial implants. While early outcomes are promising, complications such as vascular injury (VI) remain a concern, particularly due to high radial forces during valve deployment. The choice of THV type, deployment strategy, and anatomical features such as calcifications influence VI risk, potentially leading to vessel rupture and bleeding.1 This study aims to identify biomechanical markers associated with VI using in silico simulations of redo-TAVI under varying expansion conditions. A 23 mm Sapien 3 THV was deployed as both index and redo THV in a patient-specific aortic root. Three expansion levels, under, nominal, and over-expansion, were compared in terms of stresses and strains. The aortic root and THV leaflets were modelled as hyperelastic (3rd-order Ogden), with elasto-plastic properties for the stent, catheter tip, and calcifications, and elastic properties for the balloon and skirting.2 Deployment was simulated using Abaqus/Explicit in two dynamic steps: leaflet opening via catheter displacement, followed by balloon inflation using fluid cavity interaction. General contact was defined with penalty friction and hard contact, and mass scaling kept the kinetic-to-internal energy ratio below 5–10% to maintain quasi-static conditions.Results showed over-expansion increased peak stresses in the aortic root, exceeding 2.5 MPa,3 particularly in calcified regions, highlighting elevated VI risk. This work establishes a computational framework for evaluating deployment-induced injury risk in redo-TAVI, with future directions including cohort expansion, damage modelling, and different THV combinations.References Mach M, et al. Vascular complications in TAVR: incidence, clinical impact, and management. J Clin Med. 2021;10(21). Reza S, et al. A computational framework for post-TAVR cardiac conduction abnormality (CCA) risk assessment in patient-specific anatomy. Artif Organs. 2022;46(7):1305–1317. Wang Q, et al. Simulations of transcatheter aortic valve implantation: implications for aortic root rupture. Biomech Model Mechanobiol. 2015;14(1):29–38.