Influence of Crimping Process Parameters on Vascular Prostheses Mechanical Performances

Abstract

Textile prostheses made of polyethylene terephthalate fibers are commonly used to cure cardiovascular pathologies by replacing diseased arteries. Any failure of vascular surgery is not only expensive, but also unacceptable. Biocompatibility, biofunctionality and biodurability must be taken into consideration especially with the increasing life expectancy of the population. An outstanding development of vascular prostheses might be achieved by a better choice of biomaterials and an optimization of manufacturing processes, especially the crimping technique. Crimping is an "accordion"-pleat deformation, which gives the graft a radial resistance and a longitudinal compliance. It also improves the resistance of the prosthesis to kinking and external compression. The aim of the present study is to compare the effect of three thermofixing techniques used for vascular prosthesis crimping. This will help to find the crimping process that leads to the lowest reduction of the mechanical performances of the material. We have demonstrated that the heat-setting in saturated vapor introduces the best mechanical behavior of crimped woven tubes in comparison to heat-settings with dry heat and boiling water.

Development of a test bench assessing the hydrodynamic compliance of vascular prostheses

“…Moreover, these standards essentially focus on characterizing the specimen breaking stresses whether they are unidirectional (longitudinal or transversal tensile tests) or multidirectional (burst test) without taking into account the behavior in deformation or the aptitude to dilate. 26,27 By introducing mechanical fatigue to prosthetic walls, cyclic loading tests take into account the time factor and allow giving a realistic evaluation of the prosthetic compliance.…”