Anatomic Risk Factors for Type-2 Endoleak Following EVAR: A Retrospective Review of Preoperative CT Angiography in 326 patients

Abstract

We describe the anatomic characteristics on preoperative CT angiography (CTA) that predispose to type-2 endoleaks after endovascular aneurysm repair (EVAR) for an abdominal aortic aneurysms (AAA). Between 1999 and 2010, 326 patients had a CTA before and after EVAR. CTAs were reviewed for maximal sac diameter, >50% circumferential luminal thrombus, and patency of the infrarenal aortic side branches, including the inferior mesenteric artery (IMA) and L2-L5 lumbar arteries. Postoperative CTAs were reviewed for a persistent type-2 endoleak. Of 326 patients, 30.4% had a type-2 endoleak on CTA. Univariate analysis demonstrated a patent IMA, increased patent individual L2, L3, and L4 lumbar arteries, and an increased number of total patent lumbar arteries in patients with type-2 endoleak compared to those without (p < 0.001, 0.002, <0.001, <0.001, and <0.001 respectively). Sac diameter, patent L5 lumbar arteries, and >50% circumferential mural thrombus were not significantly different (p = 0.652, 0.617, and 0.16). Univariate logistic regression demonstrated increased risk of endoleak with each additional patent lumbar artery (odds ratio (OR) 1.26, p < 0.001). Multivariate analysis of the 326 patients resulted in the delineation of the optimal anatomic variables that predicted a type-2 endoleak: occluded L3 lumbar arteries (OR 0.1, p = 0.002), occluded L4 lumbar vertebral arteries (OR 0.31, p = 0.034), and IMA occlusion (OR 0.38, p = 0.008). Univariate analysis demonstrated total patent lumbar arteries as a significant predictor of type-2 endoleak. Multivariate analysis demonstrated IMA occlusion, L3 lumbar artery occlusion, and L4 lumbar artery occlusion as independently protective against type-2 endoleak after EVAR.