title: Heparin bonding does not improve patency of polytetrafluoroethylene arteriovenous grafts.
abstract: BACKGROUND
  Heparin-bonded polytetrafluoroethylene (PTFE) grafts (hepPTFE) were developed to decrease rates of graft thrombosis. Our objective was to compare the patency of arteriovenous grafts (AVGs) for dialysis access with and without heparin bonding in a tertiary care setting.
  
  
  METHODS
  Records of patients who had an AVG placed between January 2008 and June 2011 were retrospectively reviewed. Outcome measures were primary, assisted primary, and secondary patency. Marginal survival models (to account for correlation of accesses within subjects) using Cox proportional hazard regression were used for statistical comparisons.
  
  
  RESULTS
  A total of 223 patients had 265 grafts placed. Of these, 62 (23%) were hepPTFE grafts. The average age was 66 ± 15 years in the hepPTFE group and 59 ± 17 years in the non-heparin-bonded control group (PTFE; P < 0.01). Of the hepPTFE group, 39% were men, 81% were African American, 63% were diabetic, and 81% had a tunneled catheter at the time of access placement. Of the PTFE group, 35% were men, 85% were African American, 56% were diabetic, and 83% had a tunneled catheter. HepPTFE grafts failed to improve rates of primary, assisted primary, or secondary patency based on univariate analysis (hazard ratio [HR]: 1.37 [95% confidence interval {CI}: 0.99-1.88]; HR: 1.39 [95% CI: 0.98-1.96]; and HR: 1.20 [95% CI: 0.73-1.96], respectively). The number of secondary interventions was similar in the 2 groups (1.1 interventions per person-year of follow-up PTFE versus 1.4 hepPTFE; P = 0.13). A multivariable model including age, diabetes, peripheral artery disease, tobacco use, previous access placement, and tunneled catheter found that the HR for hepPTFE was not significantly different than PTFE in primary, assisted primary, or secondary patency (HR: 1.32 [95% CI: 0.91-1.90]; HR: 1.35 [95% CI: 0.91-1.99]; and HR: 1.15 [95% CI: 0.62-2.16], respectively).
  
  
  CONCLUSIONS
  hepPTFE AVGs failed to improve patency or decrease secondary interventions compared to standard PTFE grafts. Prospective studies are needed to confirm these results.
authors.affiliation: Division of Vascular Surgery, University Hospitals Case Medical Center, Cleveland, OH.
authors.forename: Matthew T
authors.initials: MT
authors.lastname: Allemang
authors.affiliation: Center for Clinical Investigation, Case Western Reserve University, Cleveland, OH.
authors.forename: Brian
authors.initials: B
authors.lastname: Schmotzer
authors.affiliation: Division of Vascular Surgery, University Hospitals Case Medical Center, Cleveland, OH.
authors.forename: Virginia L
authors.initials: VL
authors.lastname: Wong
authors.affiliation: Division of Vascular Surgery, University Hospitals Case Medical Center, Cleveland, OH.
authors.forename: Alexander
authors.initials: A
authors.lastname: Chang
authors.affiliation: Division of Vascular Surgery, University Hospitals Case Medical Center, Cleveland, OH.
authors.forename: Ryan O
authors.initials: RO
authors.lastname: Lakin
authors.affiliation: Division of Transplant Surgery, University Hospitals Case Medical Center, Cleveland, OH.
authors.forename: Kenneth J
authors.initials: KJ
authors.lastname: Woodside
authors.affiliation: Division of Vascular Surgery, University Hospitals Case Medical Center, Cleveland, OH.
authors.forename: John
authors.initials: J
authors.lastname: Wang
authors.affiliation: Division of Vascular Surgery, University Hospitals Case Medical Center, Cleveland, OH. Electronic address: vikram.kashyap@UHhospitals.org.
authors.forename: Vikram S
authors.initials: VS
authors.lastname: Kashyap
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000925:Anticoagulants / Q000008:administration & dosage*; D001166:Arteriovenous Shunt, Surgical / Q000009:adverse effects / Q000295:instrumentation*; D001807:Blood Vessel Prosthesis; D016009:Chi-Square Distribution; D020099:Coated Materials, Biocompatible; D005260:Female; D006083:Graft Occlusion, Vascular / Q000209:etiology / Q000503:physiopathology / Q000517:prevention & control; D006493:Heparin / Q000008:administration & dosage*; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009820:Ohio; D011138:Polytetrafluoroethylene; D016016:Proportional Hazards Models; D011474:Prosthesis Design; D006435:Renal Dialysis; D012189:Retrospective Studies; D012307:Risk Factors; D062606:Tertiary Care Centers; D013927:Thrombosis / Q000209:etiology / Q000503:physiopathology / Q000517:prevention & control; D013997:Time Factors; D016896:Treatment Outcome; D014654:Vascular Patency / Q000187:drug effects*
chemical_list: D000925:Anticoagulants; D020099:Coated Materials, Biocompatible; D011138:Polytetrafluoroethylene; D006493:Heparin