Novel sealing concept in the Endologix AFX unibody stent-graft

A major ongoing challenge for the endograft industry has been to create an endograft that assures the same reliable aneurysm seal afforded by surgical resection and suturing of a prosthetic graft to the abdominal aortic wall. The focus of these developmental efforts has always been the proximal neck, where the endo-graft must be firmly affixed to the aorta to prevent device movement and seal against leakage. The two mechanisms of fixation and seal, however, apply to both the proximal and the distal landing zones. Today's bifurcated stent-graft is configured much as it was two decades ago, with a short main body and long limbs, one of which must be mated to the main body after its deployment. The unibody Powerlink endograft made by Endologix, with its long main body and two innate limbs, is deployed so that it rests on the native aortoiliac bifurcation, the first and still only bifurcated endograft design to use anatomical fixation for stabilization and separate seal from fixation. The original Powerlink stent-graft has several design features that have allowed engineers to evolve new sealing technology that is featured on the company's latest iteration, the AFX Endovascular AAA System. This article reviews the approaches taken to enhance the device's ability to reduce type I endoleaks and provides some insight into the challenges of creating the perfect seal for an aortic stent-graft.