Computational design and optimization of self-expandable cardiovascular devices - Dario Carbonaro

Recorded at CDFAM Computational Design Symposium, Amsterdam , 2025 https://cdfam.com/amsterdam-2025/ Organization: Politecnico di Torino Presenter: Dario CarbonaroPresentation Abstract Self-expandable cardiovascular devices, such as vascular stents, stent-grafts, and transcatheter aortic valves (TAVs), are medical devices implanted into diseased anatomies through minimally invasive procedures. Specifically, these devices are crimped into small catheters, where they are subjected to high strains, allowing them to pass through and be placed within the anatomy. Additionally, self-expandable cardiovascular devices are commonly fabricated from nickel-titanium (NiTi) and are capable of elastically recovering their initial shape when extracted from the catheter, even after being subjected to high strains. This capability is related to the super-elastic property of NiTi, which refers to the material’s ability to elastically sustain high strains. The effectiveness of the treatment depends on the interaction between the devices and the anatomy in which they are implanted. Furthermore, the forces exerted by the devices on the anatomy depend on their design, including geometric and material characteristics. In this context, the computational design and optimization of vascular stents represents an efficient tool for improving their mechanical characteristics and consequently enhancing outcomes and safety of the treatments. In this presentation, an overview is provided on the design optimization of self-expandable cardiovascular devices, with a focus on both geometric features and material properties. Firstly, a computational framework is presented for the multi-objective shape and cross-sectional size optimization of self-expandable TAV frames, based on finite element simulations of the implantation procedure in different diseased anatomies. Secondly, a computational framework for the design of innovative self-expandable femoral stents is introduced, in which inverse homogenization topology optimization is adopted to generate 2D unit cells with prescribed mechanical characteristics of clinical relevance, incorporating geometric constraints to ensure manufacturability. Finally, a study is presented that combines experimental tests on NiTi samples with finite element analysis of stent-graft mechanical testing, highlighting the potential for designing and optimizing the mechanical properties of self-expandable cardiovascular devices by finely tuning the temperature and processing time of the material heat treatment. This is a public episode. If you would like to discuss this with other subscribers or get access to bonus episodes, visit www.designforam.com