Use of hybrid aortic stent grafts for endovascular repair of abdominal aortic aneurysms: Indications and outcomes

Background. Only two aortic stent grafts (Ancure-Guidant, Menlo Park, CA, and AneuRx-Medtronic, Sunnyvale, CA) have been FDA-approved for endovascular aortic aneurysm repair (EndoAAA). These grafts differ significantly in construction and clinical advantage, and combining components of these grafts (hybrid graft) is occasionally necessary. The role and outcome of hybrid aortic stent grafts is unknown. Methods. All EndoAAA procedures during an 18-month period (10/99-4/01) were reviewed using the hospital record and a computer registry. Endografts were classified as hybrid if components from more than one type of stent graft were used or standard if constructed from only one stent graft type. Hybrid grafts were further classified as "anticipated" or "unanticpated." Outcomes were compared between hybrid and standard grafts using Fisher's exact test. Results. One hundred forty-five EndoAAA repairs were performed (AneuRx, 67; Ancure, 70; and custom-made, 8) of which 14 (9.6%) were hybrid grafts. The majority of hybrid grafts (11) were constructed by adding AneuRx aortic or iliac cuffs to Ancure grafts. In most cases, the need for a hybrid graft was unanticipated (10) and related to an intraoperative proximal type I endoleak (7). Conversion to open operation was avoided in six patients by constructing hybrid grafts. When anticipated (4), hybrid grafts were constructed to treat complex iliac aneurysms. Outcomes in all categories were similar (P>0.05) for hybrid vs standard grafts: technical success (93 vs 99%), conversion to open AAA (7.1 vs 2.3%), vascular complications (7.1 vs 7.6%), systemic complications (21 vs 11%), endoleak (15 vs 14%), and rupture (0 vs 0%). Conclusion. The short-term safety and effectiveness of hybrid grafts are similar to those of standard grafts. Combining graft components to create hybrid grafts may increase the ability to treat complex iliac aneurysmal disease and may reduce conversions to open AAA repair. Thus, access to multiple graft types may be an important factor in the success and safety of EndoAAA repair.