Contemporary Endovascular Management of Iliac Artery Aneurysms: Bell-Bottom, Internal Iliac Exclusion, and Branch Preservation Techniques

Common iliac artery aneurysms frequently accompany abdominal aortic aneurysms and may compromise distal seal during endovascular aneurysm repair. Treatment must balance durable aneurysm exclusion with preservation of pelvic perfusion. Before the commercial availability of iliac branch devices, iliac aneurysms were commonly managed either with bell-bottom limbs to preserve the native iliac bifurcation in patients with limited common iliac ectasia or with internal iliac artery embolization and limb extension into the external iliac artery—the coil-and-cover technique. Both strategies have been largely supplanted by iliac branch reconstruction but remain appropriate when branch reconstruction is anatomically unsuitable or disproportionately complex. Society for Vascular Surgery guidelines recommend use of an FDA-approved branch endograft to maintain perfusion to at least one internal iliac artery in anatomically suitable patients, and European Society for Vascular Surgery guidelines support bilateral preservation when feasible without compromising aneurysm exclusion. The Gore Excluder Iliac Branch Endoprosthesis and Cook Zenith Iliac Branch Device provide durable internal iliac patency and favorable five-year outcomes but differ in delivery profile, anatomic requirements, conformability, and bridging-stent configuration. Although strict instructions for use limit anatomic suitability, adjunctive techniques have expanded their clinical application to include patients with internal iliac stenosis or aneurysmal disease, type Ib endoleak after prior EVAR, and isolated iliac aneurysms suitable for stand-alone repair. Parallel grafting remains an alternative for uncommon anatomies not amenable to a dedicated iliac branch device. This review examines contemporary selection among bell-bottom, coil-and-cover, and iliac branch reconstruction strategies.