Endoleak after Modular Bifurcated Stent Versus Unibody Stent Graft for Endovascular Treatment of Infrarenal Abdominal Aortic Aneurysm

Background: The purpose of our study is to report on results of endovascular aneurysm repair (EVAR) for infrarenal abdominal aortic aneurysm (AAA) and postoperative aneurysm sac diameter change, after repair with modular bifurcated and unibody aortic stent grafts. Methods: We retrospectively reviewed a prospectively maintained database of all endovascular aneurysm repair (EVAR) procedures performed for infrarenal abdominal aortic aneurysms (AAA) at a single VA institution. A total of 113 patients underwent EVAR for infrarenal AAA between October, 2008 and November, 2011. Patients were included if they underwent elective EVAR for asymptomatic infrarenal AAA greater than 5 centimeters in diameter, and if preoperative and postoperative imaging was available for review. Patients were assessed with clinical examination and CT scan at 1, 6, and 12 months and yearly thereafter. Results: Fifty patients underwent EVAR with a modular bifurcated graft: Gore Excluder (n 41, 82%), Medtronic Talent (n8, 16%), Cook Zenith (n1, 2%). Sixty-three patients underwent EVAR with the Endologix unibody design stent graft. Thirty-six patients (72%) in the modular bifurcated group met the criteria for the instructions for use (IFU) of the graft inserted (Mod-IFU), and 14 patients (28%) did not (Mod-non IFU). Fifty-two patients (83%) in the unibody group met the IFU criteria (Uni-IFU), and 11 (17%) did not (Uni-nonIFU). Overall follow-up was 20.1 months. Rate of postoperative endoleak was 27.8% in the Mod-IFU group, 28.6% in the Mod-non IFU group, and in 27.3% in the Uni-non IFU group, and 7.7% in the Uni-IFU group. Conclusions: Overall, fewer endoleaks are noted in patients meeting IFU criteria and undergoing EVAR for infrarenal AAA with unibody stent graft design.