Branched stent-grafts for endovascular repair of aortic and iliac aneurysms.

Endovascular technique, which gains access through indirect transarterial routes and isolates the aneurysm without interrupting flow, has particular advantages in aneurysms of the aortic arch and thoracoabdominal aorta. Yet progress has been slow. The necessary branched stent-grafts face several unique technical challenges. The simplest, most versatile approach involves assembling a modular stent-graft in situ from multiple parts. Techniques vary according to the presence or absence of an overlap zone, or cuff. The first cases of this type, reported over 4 years ago, had axially oriented cuffs. Recent efforts have seen the intercomponent attachment site reduced to a ring of Nitinol around a simple fenestration, with various hybrids of cuffed and fenestrated technique in between. Other advances, such as better sheaths, better covered stents, and commercial manufacture (Cook, Australia), have helped to extend the use of branched stent-grafts to a wider range of users and a wider range of aneurysms. Although their future role remains unclear, all these devices have gone beyond the proof of concept stage, and some, such as the bifurcated component for the endovascular iliac reconstruction, are ready to become standard parts of the endovascular.