Computational analysis of mechanical performance for 3D-printed biodegradable PLA cardiovascular stents

Cardiovascular stents are widely applied in the treatment of arterial stenosis, but conventional metallic stents present limitations such as permanent implantation, hypersensitivity reactions, and late restenosis. Biodegradable polymer stents offer a promising alternative, though their translation is restricted by structural design challenges and inadequate mechanical performance. In this study, eight representative stent architectures were computationally evaluated with respect to radial elastic recoil, foreshortening, dogboning, and radial support force. Stents were fabricated from polylactide (PLA) via fused deposition modelling (FDM), and the effects of nozzle temperature, layer height, and printing speed were systematically assessed on PLA dogbone specimens to determine optimised process parameters. Computational analysis revealed that only type B and type F stents met clinical deformation requirements, with radial elastic recoil <6 %, foreshortening <10 %, and dogboning <10 %, while other designs exhibited values exceeding these thresholds. Parallel compression tests further quantified radial support capacity at 50 % compression. Fabrication and dimensional evaluation showed that, although all stent designs could be produced using optimised FDM parameters, manufacturing-induced geometric deviations at thin struts and unit connection regions were unavoidable. As a result, the finite-element simulations should be regarded as providing idealised mechanical responses for comparative design evaluation rather than exact predictions of fabricated prototypes. Overall, these findings provide structural and process design guidelines for the development of mechanically reliable 3D-printed biodegradable PLA cardiovascular stents, while emphasising the importance of manufacturing fidelity when translating computationally optimised designs into physical devices.