Influence of artery and vein diameters on autogenous arteriovenous access patency

Objective: Previous investigations have suggested that a minimum venous outflow diameter (MVOD) and perianastomotic arterial diameter are associated with successful autogenous arteriovenous maturation and patency. The goal of this study was to determine anatomic and clinical variables that may influence access patency to guide optimal autogenous access configuration selection. Methods: Accesses created from 2010 to 2016 were analyzed from data entered into a prospective database. Pre-procedure duplex ultrasound mapping data of artery and tourniquet-derived vein diameters and demographic and clinical variables were collected. Survival-based cut point analysis was used to determine anatomic parameters most predictive of access failure. Kaplan-Meier and Cox proportional hazards analyses were used to assess patencies and maturation and to identify independent predictors of access failure. Results: A total of 356 first-time autogenous accesses were created (median follow-up, 20 months; range, 0-73 months). Of these, 202 (56.7%) were radiocephalic and 154 (43.3%) were brachiocephalic. Maturation failure at end of follow-up for arteriovenous accesses was 26% +/- 3% for radiocephalic accesses and 15% +/- 3% for brachiocephalic accesses (P < .001). For radiocephalic accesses, MVOD <3.0 mm and radial artery diameter <2.1 mm independently predicted access maturation failure (MVOD <3.0 mm: hazard ratio [HR], 2.62 [95% confidence interval (CI), 1.27-5.39; P = .009]; radial artery diameter <2.1 mm: HR, 2.20 [95% CI, 1.20-4.05; P = .011]) and secondary patency loss (MVOD <3.0 mm: HR, 2.21 [95% CI, 1.24-3.96; P = .007]; radial artery diameter <2.1 mm: HR, 2.11 [95% CI, 1.26-3.63; P = .004]). A combination of radial artery diameter<2.1mmandMVOD<3.0 mm most strongly predicted maturation failure (HR, 4.24; 95% CI, 1.71-10.49; P = .002) and loss of secondary patency (HR, 4.03; 95% CI, 1.88-8.64; P < .001). Only diabetesmellitus (HR, 2.24; P = .012) predicted secondary patency loss. For brachiocephalic accesses, MVOD <3.4 mm (HR, 2.12; 95% CI, 1.02-4.46; P = .043) was found to independently predict secondary patency loss in addition to previous ipsilateral (HR, 2.37; P = .038) and bilateral (HR, 4.00; P = .015) tunneled hemodialysis catheters. Brachial artery diameter was not associated with either access maturation or patency. Conclusions: Artery and tourniquet-derived vein diameters independently predict radiocephalic access patency and functional outcomes. A combination of a radial artery diameter <2.1 mm and MVOD <3.0 mm best predicts maturation failure and patency loss for radiocephalic access. MVOD <3.4 mm was associated with increased loss of brachiocephalic access secondary patency, but MVOD was not associated with maturation.