title: Impact of the Repositionable C3 Excluder System on the Endovascular Treatment of Abdominal Aortic Aneurysms With Unfavorable Neck Anatomy.
abstract: OBJECTIVE
  To analyze the midterm clinical outcomes among patients with favorable and unfavorable neck morphology for endovascular aneurysm repair (EVAR), specifically the impact of the repositionable C3 Excluder stent-graft on type I endoleak in patients with unfavorable neck.
  
  
  METHODS
  A retrospective review was conducted of 249 patients (mean age 74.3 years; 241 men) who underwent successful EVAR from January 2000 to December 2014 using either the traditional Excluder (n=140) or the C3 repositionable system (n=109). Unfavorable proximal aortic neck anatomy was defined by length <15 mm, angulation >60°, >50% circumferential thrombus, or >50% neck calcification. By these criteria, unfavorable neck anatomy was present in 71 (28.5%) patients (41 traditional Excluder and 30 C3 Excluder). The main endpoint was the incidence of type Ia endoleak and the need for a proximal cuff according to the type of neck anatomy. Comparisons between groups are reported as the odds ratio (OR) and 95% confidence interval (CI).
  
  
  RESULTS
  A proximal extension cuff for type Ia endoleak was needed in 4 (2.2%) patients with favorable neck anatomy compared to 7 (9.9%) patients with unfavorable neck (OR 4.76, 95% CI 1.3 to 16.8, p=0.014). Among the patients with unfavorable neck, a proximal cuff was implanted in 6/41 (14.6%) traditional Excluder stent-grafts vs 1/30 (3.3%) in the C3 Excluder group (OR 4.39, 95% CI 0.55 to 34.58, p=0.23). Median follow-up was 30.5 and 38 months for favorable vs unfavorable neck groups, respectively (p=0.29). Only 1 case of type Ia endoleak was registered at 6.5 years' follow-up (traditional Excluder), with no device migration.
  
  
  CONCLUSIONS
  Both Excluder stent-grafts provide good midterm clinical outcomes after EVAR in patients with unfavorable neck anatomy. Investigation of a larger cohort will be needed to identify if the C3 Excluder device offers any improvement over the traditional Excluder in terms of freedom from endoleaks.
authors.affiliation: Department of Angiology and Vascular Surgery, Hospital Clínico San Carlos, Madrid, Spain manuelahdez@hotmail.com.
authors.forename: Manuela M
authors.initials: MM
authors.lastname: Hernández Mateo
authors.affiliation: Department of Angiology and Vascular Surgery, Hospital Clínico San Carlos, Madrid, Spain.
authors.forename: Isaac
authors.initials: I
authors.lastname: Martínez López
authors.affiliation: Department of Angiology and Vascular Surgery, Hospital Clínico San Carlos, Madrid, Spain.
authors.forename: Sergio
authors.initials: S
authors.lastname: Revuelta Suero
authors.affiliation: Department of Angiology and Vascular Surgery, Hospital Clínico San Carlos, Madrid, Spain.
authors.forename: Pablo
authors.initials: P
authors.lastname: Marqués de Marino
authors.affiliation: Department of Angiology and Vascular Surgery, Hospital Clínico San Carlos, Madrid, Spain.
authors.forename: Iñaki
authors.initials: I
authors.lastname: Cernuda Artero
authors.affiliation: Department of Angiology and Vascular Surgery, Hospital Clínico San Carlos, Madrid, Spain.
authors.forename: Maday
authors.initials: M
authors.lastname: Cabrero Fernández
authors.affiliation: Department of Angiology and Vascular Surgery, Hospital Clínico San Carlos, Madrid, Spain.
authors.forename: Francisco J
authors.initials: FJ
authors.lastname: Serrano Hernando
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D017544:Aortic Aneurysm, Abdominal / Q000000981:diagnostic imaging / Q000401:mortality / Q000601:surgery*; D001027:Aortography / Q000379:methods; D001807:Blood Vessel Prosthesis; D019917:Blood Vessel Prosthesis Implantation / Q000009:adverse effects / Q000295:instrumentation* / Q000401:mortality; D016009:Chi-Square Distribution; D000072226:Computed Tomography Angiography; D018572:Disease-Free Survival; D057867:Endoleak / Q000209:etiology; D057510:Endovascular Procedures / Q000009:adverse effects / Q000295:instrumentation* / Q000401:mortality; D005260:Female; D005548:Foreign-Body Migration / Q000209:etiology; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D011474:Prosthesis Design; D012189:Retrospective Studies; D012307:Risk Factors; D013030:Spain; D015607:Stents; D013997:Time Factors; D016896:Treatment Outcome
keywords: abdominal aortic aneurysm; angulation; aortic neck; endovascular aneurysm repair; proximal neck anatomy; proximal seal