title: Endovascular aortic aneurysm repair with carbon dioxide-guided angiography in patients with renal insufficiency.
abstract: OBJECTIVE
  Renal dysfunction following endovascular abdominal aortic aneurysm repair (EVAR) remains a significant source of morbidity and mortality. We studied the use of carbon dioxide (CO(2)) as a non-nephrotoxic contrast agent for EVAR.
  
  
  METHODS
  Recorded data from 114 consecutive patients who underwent EVAR with CO(2) as the contrast agent over 44 months were retrospectively analyzed. CO(2) was used exclusively in 72 patients and in an additional 42 patients iodinated contrast (IC) was given (mean, 37 mL). Renal and hypogastric artery localization and completion angiography were done with CO(2) in all patients, including additional arterial embolization in 16 cases. Preoperative National Kidney Foundation glomerular filtration rate (GFR) classification was normal in 16 patients, mildly decreased in 52, moderate to severely decreased in 44, and two patients were on dialysis.
  
  
  RESULTS
  All graft deployments were successful with no surgical conversions. CO(2) angiography identified 20 endoleaks (two type 1, 16 type 2, and two type 4) and three unintentionally covered arteries. Additional use of IC in 42 patients did not modify the procedure in any case. When compared with a cohort of patients who underwent EVAR using exclusively IC, the operative time was shorter with CO(2) (177 vs 194 minutes; P = .01); fluoroscopy time was less (21 vs 28 minutes; P = .002), and volume of IC was lower (37 vs 106 mL; P < .001). Postoperatively, there were two deaths, two instances of renal failure requiring dialysis, and no complications related to CO(2) use. Among patients with moderate to severely decreased GFR, those undergoing EVAR with IC had a 12.7% greater decrease in GFR compared with the CO(2) EVAR group (P = .004). At 1, 6, and 12-month follow-up, computed tomography angiography showed well-positioned endografts with the expected patent renal and hypogastric arteries in all patients and no difference in endoleak detection compared with the IC EVAR group. During follow-up, eight transluminal interventions and one open conversion were required, and no aneurysm-related deaths occurred.
  
  
  CONCLUSIONS
  CO(2)-guided EVAR is technically feasible and safe; it eliminates or reduces the need for IC use, may expedite the procedure, and avoids deterioration in renal function in patients with pre-existing renal insufficiency. A prospective trial comparing CO(2) with IC during EVAR is warranted.
authors.affiliation: Department of Surgery, Section of Vascular Surgery, University of Michigan School of Medicine, Ann Arbor, MI 48109-5867, USA. ecriado@umich.edu
authors.forename: Enrique
authors.initials: E
authors.lastname: Criado
authors.forename: Gilbert R
authors.initials: GR
authors.lastname: Upchurch
authors.forename: Kate
authors.initials: K
authors.lastname: Young
authors.forename: John E
authors.initials: JE
authors.lastname: Rectenwald
authors.forename: Dawn M
authors.initials: DM
authors.lastname: Coleman
authors.forename: Jonathon L
authors.initials: JL
authors.lastname: Eliason
authors.forename: Guillermo A
authors.initials: GA
authors.lastname: Escobar
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000704:Analysis of Variance; D015901:Angiography, Digital Subtraction; D001014:Aortic Aneurysm / Q000150:complications / Q000000981:diagnostic imaging* / Q000601:surgery*; D001027:Aortography / Q000379:methods; D019917:Blood Vessel Prosthesis Implantation / Q000009:adverse effects; D002245:Carbon Dioxide / Q000009:adverse effects; D016009:Chi-Square Distribution; D003287:Contrast Media / Q000009:adverse effects; D057867:Endoleak / Q000000981:diagnostic imaging / Q000209:etiology; D057510:Endovascular Procedures / Q000009:adverse effects; D005260:Female; D005471:Fluoroscopy; D005919:Glomerular Filtration Rate; D006801:Humans; D008297:Male; D008824:Michigan; D008875:Middle Aged; D011183:Postoperative Complications / Q000000981:diagnostic imaging / Q000209:etiology; D011237:Predictive Value of Tests; D015641:Radiography, Interventional / Q000009:adverse effects / Q000379:methods*; D006435:Renal Dialysis; D051437:Renal Insufficiency / Q000150:complications* / Q000209:etiology / Q000503:physiopathology / Q000628:therapy; D012189:Retrospective Studies; D018570:Risk Assessment; D012307:Risk Factors; D012720:Severity of Illness Index; D013997:Time Factors; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome
chemical_list: D003287:Contrast Media; D002245:Carbon Dioxide