title: Comparison of aortic neck dilatation after open and endovascular repair of abdominal aortic aneurysm.
abstract: OBJECTIVE
  This study evaluated the changes of the aortic diameter at the suprarenal and infrarenal segment after open repair (OR) and endovascular repair (EVAR) of abdominal aortic aneurysms (AAAs).
  
  
  METHODS
  This was a retrospective analysis of all patients undergoing AAA repair between 1997 and 2008. Inclusion criteria were at least 3 months of follow-up at our institution, elective aneurysm repair, and absence of false, mycotic, or inflammatory aneurysms. For EVAR, standard computed tomography (CT) scans from follow-up were used; in the OR group, CT scans performed for unrelated nonvascular indications were used. Diameters of the aorta were measured at the first slice below the lowest renal artery and at the first slice above the highest renal artery. A 2-mm change was defined as measurable aortic neck dilatation.
  
  
  RESULTS
  Inclusion criteria were met by 46 patients in the OR group and 103 in the EVAR group. After a follow-up of 34.1 months (range, 5.5-131.7 months) in the OR group and 39.4 months (range, 3-108.9 months) in the EVAR group, the mean changes were 1.75 ± 3.50 mm (OR) and 0.9 ± 2.3 mm (EVAR; P = .305) in the suprarenal diameters and 0.8 ± 2.9 mm (OR) and 1.2 ± 2.5 mm (EVAR; P = .311) in the infrarenal diameters. The absolute suprarenal vs infrarenal sizes were 29.7 ± 7.1 and 28.7 ± 6.8 mm in the OR group and 28.7 ± 3.2 and 28.5 ± 3.6 mm, respectively, in the EVAR group (suprarenal, P = .749; infrarenal, P = .273). Increase of the aortic diameter >2 mm, defined as aortic neck dilatation, was found in 23 of 103 EVAR patients (22.3% ± 0.862%), and in nine of 46 OR patients (19.57% ± 0.484%; P = .870). Increase in the suprarenal change >2 mm occurred in 21 of 103 EVAR patients (20.39% ± 1.04%) and in 14 of 46 OR patients (30.4% ± 0.446%; P = .260). Reintervention rate of patients with an increase >2 mm was 31% (seven of 23) in EVAR and 11.1% (one of nine) in the OR group (P = .386).
  
  
  CONCLUSIONS
  The AAA groups treated with EVAR or OR demonstrated similar increases of aneurysmal neck diameters. This suggests that aortic neck dilatation may be caused by a natural progression of the disease rather than by deviating therapeutic strategies.
authors.affiliation: Department of Cardiothoracic and Vascular Surgery, University of Ulm, Ulm, Germany. alexander.oberhuber@corones.it
authors.forename: Alexander
authors.initials: A
authors.lastname: Oberhuber
authors.forename: Marcella
authors.initials: M
authors.lastname: Buecken
authors.forename: Martin
authors.initials: M
authors.lastname: Hoffmann
authors.forename: Karl-Heinz
authors.initials: KH
authors.lastname: Orend
authors.forename: Bernd Manfred
authors.initials: BM
authors.lastname: Mühling
mesh_terms: D000368:Aged; D017130:Angioplasty / Q000009:adverse effects / Q000379:methods*; D001012:Aorta, Abdominal / Q000000981:diagnostic imaging* / Q000473:pathology; D017544:Aortic Aneurysm, Abdominal / Q000000981:diagnostic imaging* / Q000601:surgery* / Q000628:therapy; D019917:Blood Vessel Prosthesis Implantation / Q000009:adverse effects / Q000379:methods*; D015331:Cohort Studies; D016001:Confidence Intervals; D004108:Dilatation, Pathologic / Q000000981:diagnostic imaging / Q000473:pathology; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D021621:Imaging, Three-Dimensional; D008297:Male; D008875:Middle Aged; D011184:Postoperative Period; D012189:Retrospective Studies; D018709:Statistics, Nonparametric; D014057:Tomography, X-Ray Computed / Q000379:methods; D016896:Treatment Outcome