title: Risk factors and impact of proximal fixation on acute and chronic renal dysfunction after endovascular aortic aneurysm repair using glomerular filtration rate criteria.
abstract: BACKGROUND
  The incidence of renal impairment relevant to proximal fixation of aortic endograft devices remains unclear.
  
  
  METHODS
  Retrospective cohort of 208 consecutive patients that underwent EVAR from 2006 to 2011. Estimated glomerular filtration rate (eGFR) was based on MDRD study equation. Acute kidney injury (AKI) and chronic kidney disease (CKD) were classified with ADIQ/RIFLE criteria and National Kidney Foundation criteria, respectively. Kaplan-Meier curve was applied to evaluate progression to CKD. Multivariate regression model was fit to identify predictors for developing AKI and CKD.
  
  
  RESULTS
  Suprarenal fixation group (SF) included 110 patients and infrarenal fixation group (IF) included 98 patients. Both groups had similar demographics, baseline eGFR, and renal-protection protocols. There was a trend for decreased use of contrast in IF group (median: 93.5 vs. 103 cc, P = 0.07). AKI occurred in 15% of patients in SF group and 19% of patients in IF group (RR: 1.24, P = 0.47). The freedom from progression to stage 3 or 4 CKD in the SF group was 0.76, 0.72, and 0.49 at 6, 12, and 18 months, respectively, while for IF group was 0.8, 0.73, and 0.68, respectively (P = 0.4). Increasing age (P = 0.07), lengthy procedures (P < 0.001), and baseline renal dysfunction (P < 0.001) were significant predictors for developing CKD. Contrast volume (P < 0.001) and ace-inhibitors (P = 0.07) were predictors for AKI.
  
  
  CONCLUSIONS
  Proximal fixation type has no significant effect on both acute and chronic renal function. Identification of modifiable perioperative risk factors may be used to improve renal function outcomes.
authors.affiliation: Division of Vascular Surgery and Endovascular Therapy, Michael E. DeBakey Department of Surgery, Baylor College of Medicine, Houston, TX 77030, USA. pisimisi@bcm.edu
authors.forename: George T
authors.initials: GT
authors.lastname: Pisimisis
authors.forename: Carlos F
authors.initials: CF
authors.lastname: Bechara
authors.forename: Neal R
authors.initials: NR
authors.lastname: Barshes
authors.forename: Peter H
authors.initials: PH
authors.lastname: Lin
authors.forename: Win S
authors.initials: WS
authors.lastname: Lai
authors.forename: Panagiotis
authors.initials: P
authors.lastname: Kougias
mesh_terms: D058186:Acute Kidney Injury / Q000175:diagnosis / Q000209:etiology* / Q000503:physiopathology; D000368:Aged; D000369:Aged, 80 and over; D001014:Aortic Aneurysm / Q000503:physiopathology / Q000601:surgery*; D019917:Blood Vessel Prosthesis Implantation / Q000009:adverse effects*; D018450:Disease Progression; D057510:Endovascular Procedures / Q000009:adverse effects*; D005260:Female; D005919:Glomerular Filtration Rate; D006801:Humans; D053208:Kaplan-Meier Estimate; D007668:Kidney / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D011237:Predictive Value of Tests; D051436:Renal Insufficiency, Chronic / Q000175:diagnosis / Q000209:etiology / Q000503:physiopathology*; D012189:Retrospective Studies; D018570:Risk Assessment; D012307:Risk Factors; D013997:Time Factors; D016896:Treatment Outcome