title: Correlation of pre-existing vascular pathology with arteriovenous graft outcomes in hemodialysis patients.
abstract: BACKGROUND
  Arteriovenous grafts (AVGs) are prone to neointimal hyperplasia leading to AVG failure. We hypothesized that pre-existing pathologic abnormalities of the vessels used to create AVGs (including venous intimal hyperplasia, arterial intimal hyperplasia, arterial medial fibrosis, and arterial calcification) are associated with inferior AVG survival.
  
  
  METHODS
  Prospective observational study.
  
  
  METHODS
  Patients with chronic kidney disease undergoing placement of a new AVG at a large medical center who had vascular specimens obtained at the time of surgery (n = 76).
  
  
  METHODS
  Maximal intimal thickness of the arterial and venous intima, arterial medial fibrosis, and arterial medial calcification.
  
  
  METHODS
  Unassisted primary AVG survival (time to first intervention) and frequency of AVG interventions.
  
  
  RESULTS
  55 patients (72%) underwent interventions and 148 graft interventions occurred during 89.9 years of follow-up (1.65 interventions per graft-year). Unassisted primary AVG survival was not associated significantly with arterial intimal thickness (HR, 0.72; 95% CI, 0.40-1.27; P = 0.3), venous intimal thickness (HR, 0.64; 95% CI, 0.37-1.10; P = 0.1), severe arterial medial fibrosis (HR, 0.58; 95% CI, 0.32-1.06; P = 0.6), or severe arterial calcification (HR, 0.68; 95% CI, 0.37-1.31; P = 0.3). The frequency of AVG interventions per year was associated inversely with arterial intimal thickness (relative risk [RR], 1.99; 95% CI, 1.16-3.42; P < 0.001 for thickness <10 vs. >25 μm), venous intimal thickness (RR, 2.11; 95% CI, 1.39-3.20; P < 0.001 for thickness <5 vs. >10 μm), arterial medial fibrosis (RR, 3.17; 95% CI, 1.96-5.13; P < 0.001 for fibrosis <70% vs. ≥70%), and arterial calcification (RR, 2.12; 95% CI, 1.31-3.43; P = 0.001 for <10% vs. ≥10% calcification).
  
  
  CONCLUSIONS
  Single-center study. Study may be underpowered to demonstrate differences in unassisted primary AVG survival.
  
  
  CONCLUSIONS
  Pre-existing vascular pathologic abnormalities in patients with chronic kidney disease may not be associated significantly with unassisted primary AVG survival. However, vascular intimal hyperplasia, arterial medial fibrosis, and arterial calcification may be associated with a decreased frequency of AVG interventions.
authors.affiliation: Division of Nephrology, University of Alabama at Birmingham, Birmingham, AL. Electronic address: mdallon@uab.edu.
authors.forename: Michael
authors.initials: M
authors.lastname: Allon
authors.forename: Silvio
authors.initials: S
authors.lastname: Litovsky
authors.forename: Carlton J
authors.initials: CJ
authors.lastname: Young
authors.forename: Mark H
authors.initials: MH
authors.lastname: Deierhoi
authors.forename: Jeremy
authors.initials: J
authors.lastname: Goodman
authors.forename: Michael
authors.initials: M
authors.lastname: Hanaway
authors.forename: Mark E
authors.initials: ME
authors.lastname: Lockhart
authors.forename: Michelle L
authors.initials: ML
authors.lastname: Robbin
mesh_terms: D001132:Arm / Q000098:blood supply; D001166:Arteriovenous Shunt, Surgical; D002114:Calcinosis / Q000473:pathology; D005260:Female; D005355:Fibrosis; D005500:Follow-Up Studies; D006085:Graft Survival / Q000502:physiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D058426:Neointima / Q000473:pathology*; D011183:Postoperative Complications / Q000473:pathology*; D011446:Prospective Studies; D006435:Renal Dialysis; D012307:Risk Factors; D013848:Thigh / Q000098:blood supply; D017539:Tunica Intima / Q000473:pathology; D017540:Tunica Media / Q000473:pathology; D014463:Ultrasonography
keywords: Arteriovenous graft; intimal hyperplasia; medial fibrosis; vascular calcification