title: A meta-analysis of outcomes of endovascular abdominal aortic aneurysm repair in patients with hostile and friendly neck anatomy.
abstract: BACKGROUND
  An increasing number of abdominal aortic aneurysms with unfavorable proximal neck anatomy are treated with standard endograft devices. Skepticism exists with regard to the safety and efficacy of this practice.
  
  
  METHODS
  A systematic review of the literature was undertaken to identify all studies comparing the outcomes of endovascular aneurysm repair (EVAR) in patients with hostile and friendly infrarenal neck anatomy. Hostile neck conditions were defined as conditions that were not consistent with the instructions for use of the endograft devices employed in the selected studies. Outcome data were pooled, and combined overall effect sizes were calculated using fixed or random effects models.
  
  
  RESULTS
  Seven observational studies reporting on 1559 patients (hostile anatomy group, 714 patients; friendly anatomy group, 845 patients) were included. Patients with hostile anatomy required an increased number of adjunctive procedures to achieve proximal seal compared with patients with friendly anatomy (odds ratio [OR], 3.050; 95% confidence interval [CI], 1.884-4.938). Although patients with unfavorable neck anatomy had an increased risk of developing 30-day morbidity (OR, 2.278; 95% CI, 1.025-5.063), no significant differences in the incidence of type I endoleak and reintervention rates within 30 days of treatment between the two groups were identified (OR, 2.467 and 1.082; 95% CI, 0.562-10.823 and 0.096-12.186). Patients with hostile anatomy had a fourfold increased risk of developing type I endoleak (OR, 4.563; 95% CI, 1.430-14.558) and a ninefold increased risk of aneurysm-related mortality within 1 year of treatment (OR, 9.378; 95% CI, 1.595-55.137).
  
  
  CONCLUSIONS
  Insufficient high-level evidence for or against performing standard EVAR in patients with hostile neck anatomy exists. Our analysis suggests EVAR should be cautiously used in patients with anatomic neck constraints.
authors.affiliation: Department of Vascular and Endovascular Surgery, Manchester Royal Infirmary, Central Manchester University Hospitals, Manchester, United Kingdom. Antoniou.ga@hotmail.com
authors.forename: George A
authors.initials: GA
authors.lastname: Antoniou
authors.forename: George S
authors.initials: GS
authors.lastname: Georgiadis
authors.forename: Stavros A
authors.initials: SA
authors.lastname: Antoniou
authors.forename: Ganesh
authors.initials: G
authors.lastname: Kuhan
authors.forename: David
authors.initials: D
authors.lastname: Murray
mesh_terms: D000368:Aged; D001012:Aorta, Abdominal / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery*; D017544:Aortic Aneurysm, Abdominal / Q000000981:diagnostic imaging / Q000401:mortality / Q000473:pathology / Q000601:surgery*; D001807:Blood Vessel Prosthesis; D019917:Blood Vessel Prosthesis Implantation / Q000009:adverse effects / Q000295:instrumentation / Q000401:mortality; D057867:Endoleak / Q000209:etiology / Q000628:therapy; D057510:Endovascular Procedures / Q000009:adverse effects / Q000295:instrumentation / Q000401:mortality; D005260:Female; D006801:Humans; D008297:Male; D016017:Odds Ratio; D018579:Patient Selection; D011474:Prosthesis Design; D011859:Radiography; D018570:Risk Assessment; D012307:Risk Factors; D013997:Time Factors; D016896:Treatment Outcome