title: Short-term outcomes of the C3 excluder for patients with abdominal aortic aneurysms and unfavorable proximal aortic seal zones.
abstract: BACKGROUND
  Endovascular abdominal aortic aneurysm repair (EVAR) in patients with unfavorable proximal seal zones remains challenging. The purpose of this study was to identify the incidence of proximal extension cuff usage for type I endoleaks in patients with abdominal aortic aneurysms and unfavorable necks treated with the C3 Excluder repositionable endoprosthesis compared with the traditional Excluder stent-graft.
  
  
  METHODS
  This is a retrospective review of patients undergoing EVAR with unfavorable neck anatomy from January 2010 to October 2011 using the Excluder endoprosthesis on the traditional deployment system or the C3 repositionable system. Seventy-seven patients were treated with the Excluder device, with 44 (57%) having unfavorable neck anatomy defined as proximal aortic neck length of <15 mm, neck diameter of >28 mm, neck angulation of >60°, circumferential thrombus of >50% or calcification at the proximal seal zone, or a "reverse taper" on computed tomographic angiography. Of the 44 patients with unfavorable neck anatomy, 24 patients received the C3 Excluder and 20 received the traditional Excluder.
  
  
  RESULTS
  The groups' comorbidities, aneurysm characteristics, and high-risk neck criteria were comparable. Initial success was 100% in both groups. Sixteen of the 44 patients (36%) with high-risk neck criteria required proximal extension cuffs for type I endoleaks, with 3 of the 24 patients (13%) in the C3 group compared with 13 of the 20 patients (65%) in the traditional Excluder group requiring proximal extension (P = 0.0005). Operative variables between the two groups were similar. At mean follow-up of 2 months (range: 1-6 months), there were no type I endoleaks or renal artery occlusion, and sac size regression was similar.
  
  
  CONCLUSIONS
  The C3 Excluder endoprosthesis significantly reduces the need for proximal extension cuffs in patients with unfavorable aortic neck anatomy compared with the traditional Excluder with identical short-term clinical outcomes. Repositionable grafts could increase the number of patients who can effectively be treated with EVAR.
authors.affiliation: Department of Surgery, Division of Vascular Surgery, Saint Louis University, 3635 Vista Avenue at Grand Boulevard, Saint Louis, MO 63110, USA. msmeds@slu.edu
authors.forename: Matthew R
authors.initials: MR
authors.lastname: Smeds
authors.forename: Donald L
authors.initials: DL
authors.lastname: Jacobs
authors.forename: Gary J
authors.initials: GJ
authors.lastname: Peterson
authors.forename: Brian G
authors.initials: BG
authors.lastname: Peterson
mesh_terms: D017544:Aortic Aneurysm, Abdominal / Q000000981:diagnostic imaging / Q000601:surgery*; D001027:Aortography / Q000379:methods; D001807:Blood Vessel Prosthesis; D019917:Blood Vessel Prosthesis Implantation / Q000009:adverse effects / Q000295:instrumentation*; D057867:Endoleak / Q000209:etiology; D057510:Endovascular Procedures / Q000009:adverse effects / Q000295:instrumentation*; D005260:Female; D006801:Humans; D008297:Male; D011474:Prosthesis Design; D012189:Retrospective Studies; D012307:Risk Factors; D015607:Stents; D013997:Time Factors; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome