title: Endograft limb occlusion in EVAR: iliac tortuosity quantified by three different indices on the basis of preoperative CTA.
abstract: OBJECTIVE
  To assess the incidence and outcome of graft limb occlusions after endovascular aortic repair (EVAR) of abdominal aortic aneurysm (AAA) in a high volume single centre. To quantify iliac artery tortuosity in patients with AAA and correlate this with limb occlusion.
  
  
  METHODS
  Data were collected consecutively and prospectively, and analyzed retrospectively.
  
  
  METHODS
  Patients treated with Zenith bifurcated stent grafts from January 2000 to December 2010 at a tertiary referral vascular unit were analyzed. Routine regular office follow-up with computed tomography angiography (CTA) and, subsequently, duplex ultrasound imaging was performed. Patients with limb occlusions were identified. For each index patient, two controls were obtained, one immediately preceding and one following the index patient in the consecutive cohort of EVAR patients.
  
  
  METHODS
  Demographics and CTA data on limb graft occlusions were recorded and compared with a defined control group. Three different indices were used to describe the tortuosity of the iliac vessels based on preoperative CTA: pelvic artery index of tortuosity (PAI), common iliac artery index of tortuosity (CAI), and a visual description of vessel tortuosity - the double iliac sign (DIS). Demographic data and indices were correlated for later occurring limb occlusion.
  
  
  RESULTS
  504 patients underwent EVAR and 18 patients experienced graft limb occlusion during a median follow-up of 28 months (range 0-133). Primary graft patency was 97% at 1 year and 96% at 3 years. Logistic regression showed that iliac artery tortuosity (DIS) (p = .001) and body mass index (p = .007) had a significant impact on graft patency.
  
  
  CONCLUSIONS
  A tortuous vessel on the preoperative CTA is associated with an increased risk of limb occlusion after EVAR. Adjunctive stenting of iliac segments deemed at risk is suggested, which is achieved without compromise of the aneurysm repair.
authors.affiliation: Department of Interventional Radiology, Rigshospitalet and University of Copenhagen, Denmark. Electronic address: mikkeltaudorf@gmail.com.
authors.forename: M
authors.initials: M
authors.lastname: Taudorf
authors.affiliation: Department of Vascular Surgery, Rigshospitalet and University of Copenhagen, Denmark.
authors.forename: L P
authors.initials: LP
authors.lastname: Jensen
authors.affiliation: Department of Vascular Surgery, Rigshospitalet and University of Copenhagen, Denmark.
authors.forename: K C
authors.initials: KC
authors.lastname: Vogt
authors.affiliation: Department of Interventional Radiology, Rigshospitalet and University of Copenhagen, Denmark.
authors.forename: J
authors.initials: J
authors.lastname: Grønvall
authors.affiliation: Department of Vascular Surgery, Rigshospitalet and University of Copenhagen, Denmark; Center for Clinical Education, HR & Education and University of Copenhagen, Copenhagen, Denmark.
authors.forename: T V
authors.initials: TV
authors.lastname: Schroeder
authors.affiliation: Department of Interventional Radiology, Rigshospitalet and University of Copenhagen, Denmark; Department of Vascular Surgery, Rigshospitalet and University of Copenhagen, Denmark.
authors.forename: L
authors.initials: L
authors.lastname: Lönn
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D017544:Aortic Aneurysm, Abdominal / Q000601:surgery*; D001027:Aortography / Q000379:methods; D001807:Blood Vessel Prosthesis / Q000009:adverse effects*; D005260:Female; D006083:Graft Occlusion, Vascular / Q000453:epidemiology* / Q000209:etiology; D006801:Humans; D007083:Iliac Artery / Q000601:surgery*; D015994:Incidence; D008297:Male; D008875:Middle Aged; D057234:Preoperative Period; D012189:Retrospective Studies; D018570:Risk Assessment; D015607:Stents; D016896:Treatment Outcome; D014656:Vascular Surgical Procedures / Q000009:adverse effects*
keywords: Abdominal aortic aneurysm; Endovascular; Iliac tortuosity index; Limb occlusion