Degradation behaviors and in-vivo biocompatibility of a rare earth- and aluminum-free magnesium-based stent

Biodegradable stents can provide scaffolding and anti-restenosis benefits in the short term then gradually disappear over time to free vessel, among which Mg-based biodegradable metal have been prosperously developed. In present study, a Mg-8.5Li (wt.%) alloy (RE- Al-free) with high ductility (> 40%) was processed into mini-tubes, further fabricated finished stent through laser cutting electropolishing. In-vitro degradation test performed evaluate durability of this before after balloon dilation. The influence plastic deformation residual stress (derived from dilation process) on checked assistance finite element analysis. addition, in-vivo behaviors biocompatibility were evaluated by performing implantation iliac artery minipigs. process did not lead deteriorated degradation, exhibited decent rate (0.15 mm/y) vitro, but divergent result 0.6 found vivo. almost completely degraded 3 months, revealing an insufficient time. Meanwhile, it induce possible thrombus, tolerable surrounding tissues pigs. Besides, endothelial coverage 1 month achieved even under severe condition. end, feasibility for treatment benign vascular stenosis generally discussed, perspectives future improvement Mg-Li-based proposed.