title: Risk factors associated with late aneurysmal sac expansion after endovascular abdominal aortic aneurysm repair.
abstract: OBJECTIVE
  We aimed to identify the risk factors associated with late aneurysmal sac expansion after endovascular abdominal aortic aneurysm repair (EVAR).
  
  
  METHODS
  We 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 preoperative diameter. Univariate and multivariate analyses were performed to identify associated risk factors for late sac expansion after EVAR from the following variables: age, gender, device, endoleak, antiplatelet therapy, internal iliac artery embolization, and preprocedural variables (aneurysm diameter, proximal neck diameter, proximal neck length, suprarenal neck angulation, and infrarenal neck angulation).
  
  
  RESULTS
  Univariate analysis revealed female gender, endoleak, aneurysm 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).
  
  
  CONCLUSIONS
  Our results suggest that patients with small abdominal aortic aneurysms (<60 mm) and infrarenal neck angulation ≤60° are more favorable candidates for EVAR. Intraprocedural treatments, such as prophylactic embolization of aortic branches or intrasac embolization, may reduce the risk of sac expansion in patients with larger abdominal aortic aneurysms or greater infrarenal neck angulation.
authors: Department of Radiology, Wakayama Medical University, Wakayama, Japan. momonga@wakayama-med.ac.jp.
authors: Motoki
authors: M
authors: Nakai
authors: Akira
authors: A
authors: Ikoma
authors: Hirotatsu
authors: H
authors: Sato
authors: Morio
authors: M
authors: Sato
authors: Yoshiharu
authors: Y
authors: Nishimura
authors: Yoshitaka
authors: Y
authors: Okamura
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001012:Aorta, Abdominal / Q000000981:diagnostic imaging / Q000473:pathology* / Q000601:surgery*; D017544:Aortic Aneurysm, Abdominal / Q000000981:diagnostic imaging / Q000473:pathology* / Q000601:surgery*; D001019:Aortic Rupture; D019917:Blood Vessel Prosthesis Implantation / Q000009:adverse effects / Q000379:methods; D004108:Dilatation, Pathologic / Q000601:surgery; D057867:Endoleak / Q000517:prevention & control / Q000601:surgery; D057510:Endovascular Procedures / Q000009:adverse effects / Q000379:methods; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011474:Prosthesis Design; D011859:Radiography; D012189:Retrospective Studies; D012307:Risk Factors; D015607:Stents