“…41,44 Chitosan-based polymers (polyethylene oxide CH-PEO), PVA (polyvinyl alcohol) cryogel membranes, polyethylene terephthalate (PET) or segmented polyether polyurethane (SPP) (SPU), bio-inspired salmon collagen brillar gel, heparinimpregnated collagen stent-gra, etc., have been used as coatings on stents. [45][46][47] Covered stents face many clinical challenges when it comes to a small vascular treatment and aneurysms. They possess the risk of promoting thrombosis, hyperplasia and have been Review reported to prolong the healing process.…”