Iatrogenic Groin AV Fistula Post-Catheterization: Doppler Signs
Pathogenesis and Clinical Context
An arteriovenous fistula (AVF) is a pathological connection between an artery and a vein at the puncture site, most commonly in the area of the common femoral artery post-catheterization. According to data on vascular access complications, puncture site complications (including hematoma and AV fistula) occur in 5–23% of cases and are considered early complications (Blagodir B.V., 2026).
Clinically, an iatrogenic AVF may present with a palpable thrill over the arterial puncture site in the groin (Diagnostic Medical Sonography: The Vascular System, 3ed, 2023).
Doppler Signs of AV Fistula
Characteristic ultrasound signs of an iatrogenic AV fistula:
| Sign | Description |
|---|---|
| Jet signal at the anastomosis site | High-velocity low-resistance turbulent flow; characteristic high-velocity jet signal PSV >300 cm/s (Blagodir B.V., 2026) |
| Arterialization of the vein | High-velocity turbulent (arterialized venous) flow in the vein near the anastomosis (Diagnostic Medical Sonography, 3ed, 2023; Blagodir B.V., 2026) |
| High diastolic velocity in the artery | High diastolic component of blood flow in the artery proximal to the fistula (Diagnostic Medical Sonography, 3ed, 2023) |
| Color bruit | Pronounced color bruit over the area of the common femoral artery at the anastomosis site (Diagnostic Medical Sonography, 3ed, 2023) |
Differential Diagnosis at the Puncture Site
Key conditions at the femoral artery puncture site requiring differentiation (Blagodir B.V., 2026):
Pseudoaneurysm (false aneurysm) — a pulsatile anechoic mass connected to the artery by a neck, with characteristic bidirectional to-and-fro flow in the neck and yin-yang swirling flow in the cavity on color mapping.
Hematoma — a confined collection outside the vessel lumen without blood flow inside, unlike a pseudoaneurysm.
Color Mapping Technique
In color Doppler mapping, an acquired AV fistula may demonstrate a speckled color artifact due to tissue vibration and aliasing in the fistula tract area; aliasing may be observed in areas of significant narrowing due to turbulent flow (Diagnostic Ultrasound Vascular 2nd Edition, 2025).
Angiography confirms the diagnosis by demonstrating venous system filling through the AV fistula at the level of the common femoral artery (Diagnostic Medical Sonography, 3ed, 2023).
Frequently asked questions
What is the threshold PSV value indicating the anastomosis site of an AV fistula?
The characteristic high-velocity jet signal at the anastomosis site is PSV >300 cm/s (Blagodir B.V., 2026).
How to differentiate an AV fistula from a pseudoaneurysm in duplex?
AVF is characterized by high-velocity low-resistance turbulent flow with arterialization of the vein and color bruit. A pseudoaneurysm is a mass with a neck, to-and-fro flow in the neck, and yin-yang swirling in the cavity.
What to look for in the artery proximal to the fistula?
High diastolic blood flow velocity in the artery proximal to the AVF (Diagnostic Medical Sonography, 3ed, 2023).
How does the vein near the fistula appear?
The vein near the anastomosis registers high-velocity turbulent arterialized venous flow.
What color artifact is characteristic of an acquired AV fistula?
A speckled color artifact due to tissue vibration and aliasing in the fistula tract area (Diagnostic Ultrasound Vascular 2nd Edition, 2025).