title: Bovine carotid artery biologic graft outperforms expanded polytetrafluoroethylene for hemodialysis access.
abstract: OBJECTIVE
  Arteriovenous grafts remain reliable substitutes for permanent hemodialysis access in patients without a suitable autogenous conduit. Advances in conduit design and endovascular management of access-related complications question the preference for synthetic conduits over biologic grafts in contemporary practice. In this study, we compared outcomes between a bovine carotid artery (BCA) biologic graft and expanded polytetrafluoroethylene (ePTFE) grafts for hemodialysis access in a recent cohort of patients.
  
  
  METHODS
  This was a single-institution retrospective review of 120 consecutive grafts placed in 98 patients between January 1, 2011, and June 30, 2014. Univariate methods (χ2, analysis of variance, t-test) were used to compare demographic and medical characteristics of patients who received each graft type. Kaplan-Meier, log-rank tests, univariate and multivariate logistic analyses, and Cox regression analyses were used to evaluate patency and graft complications. Outcomes were defined and analyzed according to reporting guidelines published by the Society for Vascular Surgery.
  
  
  RESULTS
  Of the 120 grafts studied, 52 (43%) were BCA and 68 (57%) were ePTFE. Successful graft use for dialysis was 96% (95% confidence interval [CI], 90%-100%) for BCA and 84% (95% CI, 74%-93%) for ePTFE (P = .055). Comparing BCA vs ePTFE, estimates for primary patency were 30% vs 43% at 1 year and 16% vs 29% at 2 years (P = .27). Primary assisted patency was 36% vs 45% at 1 year and 24% vs 35% at 2 years (P = .57). Secondary patency was 67% vs 48% at 1 year and 67% vs 38% at 2 years (P = .05). There were no differences in primary (hazard ratio [HR], 0.70; 95% CI, 0.40-1.28; P = .25) and primary assisted (HR, 0.87; 95% CI, 0.46-1.65; P = .67) patency for BCA compared with ePTFE. However, secondary patency was higher for BCA compared with ePTFE (HR, 2.92; 95% CI, 1.29-6.61; P = .01). Graft infection rates during the study period were 15.4% for BCA and 20.6% for ePTFE (P = .47). The significant predictors of graft failure were higher body mass index (HR, 1.06; 95% CI, 1.00-1.11; P = .04) and hyperlipidemia (HR, 2.94; 95% CI, 1.27-6.76; P = .01).
  
  
  CONCLUSIONS
  In this study of a recent cohort of patients who received arteriovenous grafts, primary and primary assisted patencies were similar between BCA and ePTFE grafts. However, secondary patency was higher for BCA, indicating better durability for the biologic graft than for ePTFE grafts in patients whose anatomy preclude placement of an arteriovenous fistula.
authors.affiliation: Division of Vascular Surgery, Department of Surgery, Johns Hopkins Bayview Medical Center, Baltimore, Md; Division of Vascular Surgery, University of South Florida, Tampa, Fla.
authors.forename: Isibor
authors.initials: I
authors.lastname: Arhuidese
authors.affiliation: Division of Vascular Surgery, Department of Surgery, Johns Hopkins Bayview Medical Center, Baltimore, Md.
authors.forename: Thomas
authors.initials: T
authors.lastname: Reifsnyder
authors.affiliation: Division of Vascular Surgery, Department of Surgery, Johns Hopkins Bayview Medical Center, Baltimore, Md.
authors.forename: Tasnim
authors.initials: T
authors.lastname: Islam
authors.affiliation: Division of Vascular Surgery, Department of Surgery, Johns Hopkins Bayview Medical Center, Baltimore, Md; Division of Vascular Surgery, Beth Israel Deaconess Medical Center, Boston, Mass.
authors.forename: Omar
authors.initials: O
authors.lastname: Karim
authors.affiliation: Division of Vascular Surgery, Department of Surgery, Johns Hopkins Bayview Medical Center, Baltimore, Md.
authors.forename: Besma
authors.initials: B
authors.lastname: Nejim
authors.affiliation: Division of Vascular Surgery, Department of Surgery, Johns Hopkins Bayview Medical Center, Baltimore, Md; Division of Vascular Surgery, University of Texas Medical Branch, Galveston, Tex.
authors.forename: Tammam
authors.initials: T
authors.lastname: Obeid
authors.affiliation: Division of Vascular Surgery, Department of Surgery, Johns Hopkins Bayview Medical Center, Baltimore, Md.
authors.forename: Umair
authors.initials: U
authors.lastname: Qazi
authors.affiliation: Division of Vascular Surgery, Department of Surgery, Johns Hopkins Bayview Medical Center, Baltimore, Md. Electronic address: bmalas1@jhmi.edu.
authors.forename: Mahmoud
authors.initials: M
authors.lastname: Malas
mesh_terms: D000328:Adult; D000368:Aged; D000818:Animals; D001807:Blood Vessel Prosthesis; D019917:Blood Vessel Prosthesis Implantation / Q000009:adverse effects / Q000295:instrumentation*; D015992:Body Mass Index; D002339:Carotid Arteries / Q000637:transplantation*; D002417:Cattle; D016009:Chi-Square Distribution; D005260:Female; D006083:Graft Occlusion, Vascular / Q000209:etiology / Q000503:physiopathology / Q000628:therapy; D006085:Graft Survival; D064593:Heterografts; D006801:Humans; D006949:Hyperlipidemias / Q000150:complications / Q000175:diagnosis; D053208:Kaplan-Meier Estimate; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009765:Obesity / Q000150:complications / Q000175:diagnosis; D016017:Odds Ratio; D011138:Polytetrafluoroethylene; D016016:Proportional Hazards Models; D011474:Prosthesis Design; D006435:Renal Dialysis; D019233:Retreatment; D012189:Retrospective Studies; D012307:Risk Factors; D013997:Time Factors; D016896:Treatment Outcome; D014654:Vascular Patency
chemical_list: D011138:Polytetrafluoroethylene