title: Successful restoration of arteriovenous dialysis access patency after late intervention.
abstract: BACKGROUND
  Arteriovenous dialysis access may be lost due to stenosis and thrombosis. Patency may be restored by thrombectomy or thrombolysis, but this is often not undertaken when the presentation is delayed. The success rate of delayed intervention is largely unknown.
  
  
  METHODS
  In this single-centre study, we identified all instances of arteriovenous vascular access (VA) failure treated with angioplasty, thrombectomy or thrombolysis between August 2010 and July 2013. Patency rates immediately after intervention, and after 3 months, were assessed using multilevel mixed effects logistic regression.
  
  
  RESULTS
  Sixty failures occurred in 41 accesses (38 patients). The access age at failure was 495 (316-888) days. Intervention was carried out after >48 h in 19 failures (32%). Immediate patency was achieved in 46 failures, of which 32 remained patent after 3 months. Delaying intervention increased the likelihood of achieving immediate patency (OR 0.55, 95% CI 0.31-1.0, P = 0.05). Having lost arteriovenous accesses previously increased the risk of immediate failure (OR 4.0, 95% CI 1.07-14.95, P = 0.04). There was no association between failure-to-intervention-time and 3-month patency rates (P = 0.23). Effect estimates did not differ between arteriovenous fistulae and synthetic arteriovenous grafts.
  
  
  CONCLUSIONS
  Delayed intervention for failed arteriovenous VA may result in superior early patency rates and yields equivalent 3-month patency rates.
authors.affiliation: Division of Renal Medicine , Norfolk and Norwich University Hospital , Norwich , UK.
authors.forename: Ragada
authors.initials: R
authors.lastname: El-Damanawi
authors.affiliation: Division of Renal Medicine , Norfolk and Norwich University Hospital , Norwich , UK.
authors.forename: Stephanie
authors.initials: S
authors.lastname: Kershaw
authors.affiliation: Division of Renal Medicine , Norfolk and Norwich University Hospital , Norwich , UK.
authors.forename: Gary
authors.initials: G
authors.lastname: Campbell
authors.affiliation: School of Clinical Medicine , University of Cambridge , Cambridge , UK.
authors.forename: Thomas F
authors.initials: TF
authors.lastname: Hiemstra
keywords: arteriovenous; dialysis; fistula; salvage; thrombosis