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Fenestration in endovascular grafts for aortic aneurysm repair: new horizons for preserving blood flow in branch vessels.

PURPOSE
To describe techniques for deploying fenestrated stent-grafts that use partial graft deployment and guided tracking of the fenestration to the arterial orifice.


TECHNIQUE
Fenestrations have been added to custom-made tube grafts and commercially manufactured Zenith stent-graft systems to preserve perfusion of aortic side branches. Partial device deployment, orientation markers on the endograft, and intraoperative angiography enable maneuvering of the fenestration over the orifice of the target vessel with the aid of guiding catheters. Placement of a Palmaz stent overlapping the fenestration and vessel orifice secures the junction. Two variations of fenestration have preserved blood flow in renal arteries during endovascular repair of abdominal aortic aneurysms (AAAs); similar techniques have maintained flow to the celiac axis in a thoracic aortic aneurysm.


CONCLUSIONS
Accurate placement of a fenestration over the orifice of a target vessel is feasible, but long-term maintenance of position is dependent on secure graft fixation. This capability brings us a step closer to overcoming the problem of inadequate necks in infra-renal AAAs, especially when the neck is foreshortened by asymmetry of the renal origins. It may also pave the way for the eventual replacement of the entire aorta with an endoluminal graft.