title: Impact of Age and Intraluminal Thrombus Volume on Abdominal Aortic Aneurysm Sac Enlargement after Endovascular Repair.
abstract: BACKGROUND
  Abdominal aneurysmal sac enlargement after endovascular aortic repair (EVAR) is a critical issue. However, the predictors have not yet been fully determined. Although unrecognized, intraluminal thrombus volume (ITV) is an important index. Therefore, we retrospectively evaluated the correlation among preoperative ITV, residual type II endoleak, and sac enlargement after EVAR, based on the long-term follow-up.
  
  
  METHODS
  Between 2006 and 2011, 151 consecutive patients underwent EVAR at a single cardiovascular institute. Emergency surgery was performed on 7 patients (4.7%). Of 148 patients excluding 3 patients with residual type I endoleak, sac enlargement (≥5 mm progression) after EVAR was observed in 24 patients (16.2%) and 8 patients required reintervention. The mean follow-up period was 2.4 ± 1.4 years. The outer volume and enhanced luminal volume were calculated from enhanced 1-mm slice computed tomography, and the difference was defined as ITV.
  
  
  RESULTS
  Age (hazard ratio [HR] 1.12, 95% confidence interval [CI] 1.04-1.20, P = 0.0007), outer volume (HR 1.04, 95% CI 1.01-1.07, P = 0.0118), percentage of ITV (HR 0.90, 95% CI 0.84-0.96, P = .0027), and type II endoleak (HR 10.15, 95% CI 3.55-31.10, P < 0.0001) were isolated as predictors of sac enlargement by multivariate analysis. Also, patent inferior mesenteric artery (odds ratio [OR] 4.45, 95% CI 1.38-20.07, P = 0.0105) and percentage of ITV < 30.1% (OR 3.52, 95% CI 1.32-10.30, P = 0.0112) were detected as independent risk factors for residual type II endoleaks. Additionally, in patients without endoleak, patient age (≥83 years) was an independent risk factor for sac enlargement after EVAR (P = 0.0056).
  
  
  CONCLUSIONS
  Age and ITV percentage had significantly great impact on sac enlargement and type II endoleak after EVAR.
authors.affiliation: Department of Cardiovascular Surgery, The Sakakibara Heart Institute of Okayama, Okayama, Japan. Electronic address: bassbord1028@yahoo.co.jp.
authors.forename: Arudo
authors.initials: A
authors.lastname: Hiraoka
authors.affiliation: Department of Cardiovascular Surgery, The Sakakibara Heart Institute of Okayama, Okayama, Japan.
authors.forename: Genta
authors.initials: G
authors.lastname: Chikazawa
authors.affiliation: Department of Cardiovascular Surgery, The Sakakibara Heart Institute of Okayama, Okayama, Japan.
authors.forename: Atsuhisa
authors.initials: A
authors.lastname: Ishida
authors.affiliation: Department of Cardiovascular Surgery, The Sakakibara Heart Institute of Okayama, Okayama, Japan.
authors.forename: Koichi
authors.initials: K
authors.lastname: Miyake
authors.affiliation: Department of Cardiovascular Surgery, The Sakakibara Heart Institute of Okayama, Okayama, Japan.
authors.forename: Toshinori
authors.initials: T
authors.lastname: Totsugawa
authors.affiliation: Department of Cardiovascular Surgery, The Sakakibara Heart Institute of Okayama, Okayama, Japan.
authors.forename: Kentaro
authors.initials: K
authors.lastname: Tamura
authors.affiliation: Department of Cardiovascular Surgery, The Sakakibara Heart Institute of Okayama, Okayama, Japan.
authors.forename: Taichi
authors.initials: T
authors.lastname: Sakaguchi
authors.affiliation: Department of Cardiovascular Surgery, The Sakakibara Heart Institute of Okayama, Okayama, Japan.
authors.forename: Hidenori
authors.initials: H
authors.lastname: Yoshitaka
mesh_terms: D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D017544:Aortic Aneurysm, Abdominal / Q000175:diagnosis / Q000601:surgery*; D001027:Aortography / Q000379:methods; D019917:Blood Vessel Prosthesis Implantation / Q000009:adverse effects*; D016009:Chi-Square Distribution; D057867:Endoleak / Q000175:diagnosis / Q000209:etiology*; D057510:Endovascular Procedures / Q000009:adverse effects*; D005260:Female; D006801:Humans; D007564:Japan; D053208:Kaplan-Meier Estimate; D008297:Male; D015999:Multivariate Analysis; D016017:Odds Ratio; D016016:Proportional Hazards Models; D012189:Retrospective Studies; D018570:Risk Assessment; D012307:Risk Factors; D013927:Thrombosis / Q000175:diagnosis / Q000601:surgery*; D013997:Time Factors; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome