Identifying problematic arteriovenous fistula with CFD-derived resistance: An exploratory study

Area of Science:

• Biomedical Engineering
• Medical Imaging
• Vascular Surgery

Background:

• Arteriovenous fistulas (AVFs) are crucial for hemodialysis but prone to stenoses.
• Stenotic lesions compromise AVF function and longevity.
• Pathological flow dynamics contribute to intimal hyperplasia and stenosis formation.

Purpose of the Study:

• To evaluate the utility of computational fluid dynamics (CFD)-derived resistance as a non-invasive metric for identifying diseased AVFs.
• To assess the impact of interventions on CFD-derived resistance in patients with access dysfunction.

Main Methods:

• Patient-specific 3D ultrasound imaging was used to capture AVF geometry and flow profiles.
• CFD simulations were performed to calculate resistance in radiocephalic AVFs before and after treatment.
• Six cases of AVF dysfunction treated with nitinol stents were analyzed.

Main Results:

• A 77% decrease in CFD-derived resistance was observed post-intervention for access dysfunction.
• High venous segment resistance correlated with problematic AVFs, while low resistance indicated patency.
• CFD-derived resistance identified stenoses independently of standard sonographic criteria.

Conclusions:

• CFD-derived resistance is a promising non-invasive tool for identifying diseased AVFs.
• This metric aids in surveillance, surgical planning, and predicting outcomes for AVF interventions.
• The analysis pipeline offers clinical utility for managing hemodialysis access.