Stent graft treatment for abdominal aortic aneurysm repair: recent developments in therapy

Minimally invasive endovascular techniques for the treatment of abdominal aortic aneurysms have significantly reduced the morbidity of these procedures compared with standard surgical repair. In addition, patients with extensive comorbid medical illnesses in whom standard operative repair is contraindicated may be successfully treated using endovascular means.

Recently, several important developments have significantly advanced this area of treatment. The Food and Drug Administration has approved four endovascular stent grafts for the treatment of abdominal aortic aneurysms: the Medtronic AneuRx, the W.L. Gore Excluder, the Cook Zenith, and the Guidant Ancure. The Zenith received approval for marketing in 2003 and has gained relatively wide use, in part because of its ability to treat aneurysms with relatively large-diameter implantations zones. Also in 2003, Guidant Corporation withdrew the Ancure graft from marketing and distribution. The withdrawal was influenced by difficulties encountered using the graft's delivery system and improper reporting to the Food and Drug Administration. Enrollment has also been recently completed for the phase II Food and Drug Administration trials of the Medtronic Talent graft and the Cordis Fortron graft. These devices have been approved for use in the European Union and are awaiting Food and Drug Administration panel meeting in the United States. Several significant advances have also occurred recently in stent graft research and development. Of particular significance has been the initiation of the phase I trial of the Trivascular Enovus graft. Deployment of the Trivascular graft may be accomplished through a delivery system that is considerably reduced in profile. The potential for percutaneous application of the graft may be available in the future. In selecting the specific stent graft to be used for endovascular abdominal aortic aneurysm repair, the specific graft characteristics must be considered, particularly with regard to the individual patient's anatomic and physiologic characteristics. Comparative analysis of the several of the various stent grafts has been performed. Results have varied with regard to the need for secondary interventions, aneurysm sac size reduction, and the occurrence of continued perfusion of the aneurysm sac. In addition, the indications for use of endovascular grafts compared with standard open surgery have not yet been fully defined.

This article describes the general principles of use for endovascular devices for the repair of abdominal aortic aneurysms. It details the features and results for the devices in current use, and highlights the recent developments in stent graft treatment of abdominal aortic aneurysms.