Computational design and analysis of biocompatible shape memory polymer-based self-expandable stent

Cardiovascular stents keep blood vessels open, but balloon-expandable designs can expand unevenly and potentially harm vessels. This work targets a self-expandable, biodegradable stent made from shape-memory polymers (SMPs). The authors model a hexagonal-nested lattice stent geometry in SOLIDWORKS and analyze it with finite elements under physiological internal pressure. They also evaluate thermo-mechanical deployment using an SMP heating/cooling sequence to assess shape fixity and recovery. Results indicate that reducing the number of circumferential cells from 7 to 5 lowers peak von Mises stress, leading to selection of the five-cell design. For PLLA, the reported shape fixity is high (95%) and recovery is near-complete (>99%), with negligible expansion stresses, while PLGA shows inferior shape-memory metrics and is not pursued for detailed stress comparison. The paper concludes that SMP-based biodegradable stents could combine low deployment stress with adequate radial support, and that the computational workflow can support later prototyping and in vitro validation.