Secondary conversion due to failed endovascular abdominal aortic aneurysm repair.

Abstract

Since Parodi et al reported their initial experience with endograft placement in patients with abdominal aortic aneurysm (AAA) more than a decade ago, endovascular repair has become an increasingly accepted treatment option for aneurysmal disease. Currently three endovascular grafts have been approved by the US Food and Drug Administration (FDA), namely, AneuRx, Ancure, and Excluder, and a number of other devices are at various stages of FDA review. Endovascular repair of infrarenal AAA has been extensively investigated, with encouraging short-term results. There is little doubt that endovascular repair of AAA is equivalent to open repair in the short term. The enthusiasm for this minimally invasive treatment is driven in part by shorter hospital course, decreased anesthetic risk, and expedient convalescent period, compared with the conventional open operation. Along with numerous positive short-term and mid-term reports of AAA endovascular repair, a growing number of reports are beginning to reveal some of the limitations of this evolving technology. Problems with device integrity, component separation, migration, infection, iliac limb occlusion, and aneurysm sac expansion with and without the presence of endoleak have been described. Many of these problems have resulted in device explantation and repair of the aneurysm with an open surgical approach. Explantation of an endovascular graft is reported as primary conversion if it is removed at the original endovascular grafting procedure, and as secondary conversion if it is removed sometime after the original endovascular grafting procedure. Clearly the rate of primary conversion has been significantly reduced with improved device design, patient selection, and increasing operator experience. Recently several investigators reported their rate of secondary conversion. Lyden et al evaluated 110 patients who received endovascular AAA treatment, 5 (4.5%) of whom required secondary conversion. Dattilo et al reported a secondary conversion rate of 2.2% (8 patients) over 7 years in 362 AAA endovascular grafts. Finally, Ohki et al, in a 9-year experience with 239 endovascular grafts, reported a secondary conversion rate of 2.1% (5 patients). In this article we review our experience in patients with late endovascular graft clinical failure in whom secondary conversion was required. In addition, we examine the indications, operative strategies, and technical maneuvers that may facilitate endograft explantation.