Elastic response of filament wound arterial prostheses under internal pressure

Filament wound synthetic prostheses have anisotropic material properties and are therefore able to match closely the elastic properties of the replaced host vessels. Highly porous prosthesis walls are required to allow ingrowth of capillar cells from the outer surface of the graft in order to increase endothelium coverage of the luminal surface. The coating of highly porous grafts with biodegradable polymers has been shown to result in a sealed structure at the time of implantation followed by controlled porosity during the healing process. Accordingly, a new manufacturing process for a coated filament wound vascular graft is proposed in this work, which combines high potential porosity with high mechanical compliance. In vitro testing of its mechanical properties shows that the compliance can be controlled by changing the reinforcement angle and the coating material. Whereas the initial compliance of the coated structure expresses a composite material response, the post-degradation compliance reflects the highly compliant response of the filament wound non-woven scaffold. Hence, higher compliance values can be achieved by the proposed technique, compared with those of the commonly used synthetic grafts.