Vasculature graft materials are generally of two main types, woven Dacron textile and expanded polytetrafluoroethylene (ePTFE). Both of these materials are synthetic materials and only marginally tolerated by the body. In the case of stent grafts, they are subject to wear because they are assembled to metallic spring expansion members, commonly known as stents, which cause wear of the graft material at attachment points. In addition, these synthetic grafts are relatively thick and when they are collapsed for introduction into the body through introducer sheaths, they require very large sheaths, making percutaneous introduction very difficult.
USPTO Backgrounds
USPTO Backgrounds