Diagnostic accuracy of peak vein velocity ratio for innominate vein stenosis in haemodialysis patients with long-term non-cuffed right internal jugular catheters

Objective: To evaluate the diagnostic accuracy of ultrasound-derived peak vein velocity ratio for detecting central vein stenosis in the innominate vein resulting from long-term non-cuffed double-lumen haemodialysis catheters. Methods: A cross-sectional study was conducted on haemodialysis patients with right internal jugular vein catheters. All subjects underwent duplex ultrasound to calculate peak vein velocity ratio, defined as the ratio of peak velocity in the innominate vein to the pre-stenotic internal jugular vein. Venography was performed as the gold standard. Results: Of 50 patients analysed, innominate vein stenosis prevalence was 68%. Diabetes mellitus was significantly associated with stenosis (odds ratio = 5.16; p = 0.049). An innominate-to-internal jugular vein peak vein velocity ratio cutoff of ⩾1.65 identified innominate vein stenosis (>30% luminal narrowing) with 97.1% sensitivity, 56.2% specificity, and an area under the curve of 0.71. Conclusion: Peak vein velocity ratio shows high sensitivity and negative predictive value as a screening tool for catheter-related innominate vein stenosis. A cutoff of 1.65 makes significant stenosis unlikely when not exceeded, supporting a possible role as a non-invasive triage step before venography in resource-limited settings, pending external validation.