| Intracranial and abdominal aortic aneurysms are frequent and potentially life threatening conditions. Minimally invasive techniques have been developed as alternatives to surgery, to reduce treatment-related morbidity and to fasten recovery.; CHEM is a shape memory polyurethane with appealing properties for the endovascular treatment of aneurysms. It's shape memory permits miniaturisation and transcatheter delivery to reach the treatment site, where it expands with temperature to occlude the aneurysmal sac.; CHEM biocompatibility has been demonstrated in vitro. Canine experimental aneurysms were occluded per-operatively with CHEM blocks. Canine internal maxillary arteries were also occluded with CHEM using a transcatheter technique. The angiographic evolution and tissue reaction to CHEM have been studied at 3 weeks and 3 months.; The use of 2 other polymers has also been explored. Intraoperative and endovascular alginate embolization is feasible and could be useful for in situ growth factor delivery. Poloxamer, a thermoreversible gel, can provide a safe temporary and reversible arterial occlusion, and as such could be used to deliver molecules to the arterial wall using a transcatheter technique.; Certain properties of CHEM, such as its shape memory, porosity, low thrombogenicity and low inflammatory response are promising for the design of embolic tools. CHEM embolization caused complete and permanent occlusion of maxillary arteries. Aneurysms treated with CHEM did not show significant recanalisation at 3 months. Additional work should be done to improve miniaturization of the material to meet requirements for the transcatheter delivery to cerebral aneurysms. The use of CHEM as an embolic agent in the treatment of aortic aneurysms in combination with stent-grafts is more realistic and should be evaluated.; These polymers (CHEM, alginate and poloxamer) are promising materials for the development of a "bioactive" strategy designed to improve results of endovascular treatment of aneurysms. |
