Arteriovenous Fistula Maturation, Functional Patency, and Intervention Rates.

Importance: National initiatives have emphasized the use of autogenous arteriovenous fistulas (AVFs) for hemodialysis, but their purported benefits have been questioned. Objective: To examine AVF usability, longer-term functional patency, and remedial procedures to facilitate maturation, manage complications, or maintain patency in the Hemodialysis Fistula Maturation (HFM) Study. Design, Setting, and Participants: The HFM Study was a multicenter (n = 7) prospective National Institutes of Health National Institute of Diabetes and Digestive and Kidney Diseases cohort study performed to identify factors associated with AVF maturation. A total of 602 participants were enrolled (dialysis, kidney failure: 380; predialysis, chronic kidney disease [CKD]: 222) with AVF maturation ascertained for 535 (kidney failure, 353; CKD, 182) participants. Interventions: All clinical decisions regarding AVF management were deferred to the individual centers, but remedial interventions were discouraged within 6 weeks of creation. Main Outcomes and Measures: In this case series analysis, the primary outcome was unassisted maturation. Functional patency, freedom from intervention, and participant survival were summarized using Kaplan-Meier analysis. Results: Most participants evaluated (n = 535) were men (372 [69.5%]) and had diabetes (311 [58.1%]); mean (SD) age was 54.6 (13.6) years. Almost two-thirds of the AVFs created (342 of 535 [64%]) were in the upper arm. The AVF maturation rates for the kidney failure vs CKD participants were 29% vs 10% at 3 months, 67% vs 38% at 6 months, and 76% vs 58% at 12 months. Several participants with kidney failure (133 [37.7%]) and CKD (63 [34.6%]) underwent interventions to facilitate maturation or manage complications before maturation. The median time from access creation to maturation was 115 days (interquartile range [IQR], 86-171 days) but differed by initial indication (CKD, 170 days; IQR, 113-269 days; kidney failure, 105 days; IQR, 81-137 days). The functional patency for the AVFs that matured at 1 year was 87% (95% CI, 83.2%-90.2%) and at 2 years, 75% (95% CI, 69.7%-79.7%), and there was no significant difference for those receiving interventions before maturation. Almost half (188 [47.5%]) of the AVFs that matured had further intervention to maintain patency or treat complications. Conclusions and Relevance: The findings of this study suggest that AVF remains an accepted hemodialysis access option, although both its maturation and continued use require a moderate number of interventions to maintain patency and treat the associated complications.

Access-related hand ischemia and the Hemodialysis Fistula Maturation Study.

OBJECTIVE: Access-related hand ischemia (ARHI) is a major complication after hemodialysis access construction. This study was designed to prospectively describe its incidence, predictors, interventions, and associated access maturation. METHODS: The Hemodialysis Fistula Maturation Study is a multicenter prospective cohort study designed to identify predictors of autogenous arteriovenous access (arteriovenous fistula [AVF]) maturation. Symptoms and interventions for ARHI were documented, and participants who received interventions for ARHI were compared with other participants using a nested case-control design. Associations of ARHI with clinical, ultrasound, vascular function, and vein histologic variables were each individually evaluated using conditional logistic regression; the association with maturation was assessed by relative risk, Pearson χ(2) test, and multiple logistic regression. RESULTS: The study cohort included 602 participants with median follow-up of 2.1 years (10th-90th percentiles, 0.7-3.5 years). Mean age was 55.1 ± 13.4 (standard deviation) years; the majority were male (70%), white (47%), diabetic (59%), smokers (55%), and on dialysis (64%) and underwent an upper arm AVF (76%). Symptoms of ARHI occurred in 45 (7%) participants, and intervention was required in 26 (4%). Interventions included distal revascularization with interval ligation (13), ligation (7), banding (4), revision using distal inflow (1), and proximalization of arterial inflow (1). Interventions were performed ≤7 days after AVF creation in 4 participants (15%), between 8 and 30 days in 6 (23%), and >30 days in 16 (63%). Female gender (odds ratio, 3.17; 95% confidence interval, 1.27-7.91; P = .013), diabetes (13.62 [1.81-102.4]; P = .011), coronary artery disease (2.60 [1.03-6.58]; P = .044), higher preoperative venous capacitance (per %/10 mm Hg, 2.76 [1.07-6.52]; P = .021), and maximum venous outflow slope (per [mL/100 mL/min]/10 mm Hg, 1.13 [1.03-1.25]; P = .011) were significantly associated with interventions; a lower carotid-femoral pulse wave velocity and the outflow vein diameter in the early postoperative period (days 0-3) approached significance (P < .10). Intervention for ARHI was not associated with AVF maturation failure (unadjusted risk ratio, 1.18 [0.69-2.04], P = .56; adjusted odds ratio, 0.97 [0.41-2.31], P = .95). CONCLUSIONS: Remedial intervention for ARHI after AVF construction is uncommon. Diabetes, female gender, capacitant outflow veins, and coronary artery disease are all associated with an increased risk of intervention. These higher risk patients should be counseled preoperatively, their operative plans should be designed to reduce the risk of hand ischemia, and they should be observed closely.