Two-week postoperative duplex ultrasound as a clinical workflow tool for risk stratification of radiocephalic arteriovenous fistulas.

BACKGROUND: Radiocephalic arteriovenous fistulas (RCAVFs) are the preferred initial haemodialysis access but are limited by high non-maturation rates, particularly in populations with smaller vessels and high diabetic burden. Preoperative duplex ultrasound (DUS) guides vessel selection but inconsistently predicts postoperative haemodynamic adaptation. We evaluated whether a standardised 2-week postoperative DUS checkpoint could function as a clinical workflow tool for early risk stratification and long-term patency prediction.

METHODS: In this prospective single-centre study, 57 patients undergoing primary RCAVF creation were followed for up to 10 years. Two-week postoperative DUS assessed vein diameter (VD), brachial artery flow (BAF) and resistive index (RI). Receiver operating characteristic analysis identified thresholds predicting 6-week Kidney-Disease-Outcomes-Quality-Initiative-defined maturation. Kaplan-Meier and Cox regression analyses evaluated long-term primary (PP) and secondary patency (SP).

RESULTS: Six-week maturation occurred in 56%, and functional maturation in 61% of patients initiated on dialysis. Two-week VD demonstrated the strongest discrimination for maturation (AUC 0.81, 95% CI 0.50-0.84, p = 0.01), followed by BAF (AUC 0.72, 95% CI 0.65-0.90, p = 0.02). RI showed weaker performance (AUC 0.67, 95% CI 0.50-0.83, p = 0.05). A VD <5 mm independently predicted long-term PP loss up to 10 years (HR 2.43, 95% CI 1.21-4.86, p = 0.01). BAF predicted early maturation but not long-term PP and SP. Early vein and flow expansion kinetics were not independently associated with long-term outcomes.

CONCLUSIONS: A 2-week postoperative DUS checkpoint provides actionable early structural risk stratification after RCAVF creation. Early structural calibre reflects adaptive remodelling and independently predicts long-term PP, supporting integration of this checkpoint into routine practice.