ARRS 2022 Abstracts

RETURN TO ABSTRACT LISTING


E1920. Keep It Flowing: Ultrasound Imaging of Hemodialysis Arteriovenous Fistulas and Grafts
Authors
  1. Sriram Rao; Department of Radiological Sciences, University of California, Irvine
  2. Thanh-Lan Bui; Department of Radiological Sciences, University of California, Irvine
  3. Ali Sasani; Department of Radiological Sciences, University of California, Irvine
  4. Louis Fanucci; Department of Radiological Sciences, University of California, Irvine
  5. Peter Wang; Department of Radiological Sciences, University of California, Irvine
  6. Roozbeh Houshyar; Department of Radiological Sciences, University of California, Irvine
  7. Alexander Ushinsky; Mallinckrodt Institute of Radiology
Background
Hemodialysis is a necessary, life-saving procedure for patients with end stage renal disease and renal failure. It allows for arterial blood to be removed from a patient’s body to filter out toxins before being replaced into the venous system. Arteriovenous (AV) fistulas and AV grafts are two types of vascular access that can be used for long-term hemodialysis. AV fistulas for hemodialysis are iatrogenic connections made directly between an artery and vein. Similarly, AV grafts connect arteries and veins but do so through the use of a graft, usually polytetrafluoroethylene. Common complications of hemodialysis vascular access creation include non-maturity, vessel stenosis, thrombosis or occlusion, hematoma, pseudoaneurysm and/or aneurysm formation, among others.

Educational Goals / Teaching Points
This education exhibit will review the anatomy for the most common types of upper extremity AV fistulas and grafts. In addition, using representative cases, we will describe the presentation, ultrasound, and waveform findings for different complications/pathologies that can be acquired in hemodialysis upper extremity AV grafts and fistulas.

Key Anatomic/Physiologic Issues and Imaging Findings/Techniques
AV fistula and AV grafts are most commonly created in the upper extremities. Depending on the vessels used, there are several types. Forearm AV fistulas can be between the radial artery and cephalic vein or radial artery and basilic vein. Forearm grafts are done between the brachial artery and median antecubital vein. Upper arm AV fistulas are between the brachial artery and cephalic vein or brachial artery and basilic vein. Upper arm grafts are between the brachial artery and the high brachial vein or between the brachial artery and basilic vein. Dual outflow fistulas use two veins; they can be between the brachial artery and both the cephalic and basilic veins or between the radial artery and cephalic and basilic veins. Ultrasound is used to map the vasculature in the upper extremities for preoperative planning. Veins of sufficient size are analyzed with ultrasound all the way back to the subclavian vein for stenosis or occlusion by both compression and non-compressive assessment. In addition to mapping the upper arm vasculature, ultrasound can be used to assess draining veins. Post AV fistula or AV graft formation, ultrasound can assist in assessing fistula or graft patency and identify and characterize any complications.

Conclusion
Ultrasound is a safe, accurate, and pragmatic way to characterize vasculature in the upper extremities both prior to and after creation of dialysis access. It is essential for radiologists to understand how to use ultrasound in preoperative vessel mapping, analysis of draining veins, postoperative characterization of AV fistulas and AV grafts, and diagnosis of complications.