Stent Grafts for Aortic Aneurysms: the Next Interventional Challenge

Stent grafts (endografts) have proved useful for the endoluminal exclusion of peripheral and aortic aneurysms, both those in native arteries and those resulting from prior surgery. In addition, their use may apply in some patients with occlusive vascular disease. Various types of endografts are being evaluated in clinical trials, including those that utilize unsupported grafts with stentlike attachment mechanisms and those having a metallic endoskeleton or exoskeleton. Relatively complex devices can be delivered through small arteriotomies and in some cases percutaneous approaches. Unsupported grafts, although more prone to kinking and incomplete expansion, appear to work well. Some devices employ modularity, which involves separate placement of contralateral limbs and, in some cases, extension devices. For performing endovascular grafting, pretreatment planning is critical and requires sophisticated imaging, including spiral computed tomography (CT) with 3-dimensional reconstruction and angiographic evaluation using catheters with calibrated markers. Potential advantages of endovascular grafts include a decreased hospital stay, a less invasive procedure, and lower morbidity and mortality. Several issues remain unresolved and should be addressed by the newer generation of these devices.