Risk factors associated with late aneurysmal sac expansion after endovascular abdominal aortic aneurysm repair

Abstract

PURPOSEWe aimed to identify the risk factors associated with late an-eurysmal sac expansion after endovascular abdominal aortic aneurysm repair (EVAR).METHODSWe retrospectively reviewed contrast-enhanced computed tomography (CT) images of 143 patients who were followed for >=6 months after EVAR. Sac expansion was defined as an increase in sac diameter of 5 mm relative to the preoper-ative diameter. Univariate and multivariate analyses were performed to identify associated risk factors for late sac ex-pansion after EVAR from the following variables: age, gender, device, endoleak, antiplatelet therapy, internal iliac artery embolization, and preprocedural variables (aneurysm diam-eter, proximal neck diameter, proximal neck length, suprare-nal neck angulation, and infrarenal neck angulation).RESULTSUnivariate analysis revealed female gender, endoleak, aneu-rysm diameter >=60 mm, suprarenal neck angulation >45°, and infrarenal neck angulation >60° as factors associated with sac expansion. Multivariate analysis revealed endoleak, aneurysm diameter >=60 mm, and infrarenal neck angulation >60° as independent predictors of sac expansion (P < 0.05, for all).CONCLUSIONOur results suggest that patients with small abdominal aortic aneurysms (<60 mm) and infrarenal neck angulation <=60° are more favorable candidates for EVAR. Intraprocedural treat-ments, such as prophylactic embolization of aortic branches or intrasac embolization, may reduce the risk of sac expan-sion in patients with larger abdominal aortic aneurysms or greater infrarenal neck angulation.