[Doppler echo in evaluating arteriovenous fistulae for dialysis]

Area of Science:

• Vascular Surgery
• Diagnostic Imaging
• Nephrology

Background:

• Arteriovenous fistulas (FAVs) are crucial for hemodialysis access.
• Noninvasive functional evaluation of FAVs is essential for patient care.
• Ultrasound Doppler (US-Doppler) has emerged as a promising tool for FAV assessment.

Purpose of the Study:

• To assess the utility of US-Doppler for functional evaluation of arteriovenous fistulas (FAVs).
• To identify key US-Doppler parameters indicative of FAV functionality.

Main Methods:

• Studied 20 patients with well-functioning FAVs and 10 healthy controls.
• Measured time average velocity (TAV), telesystolic (Vts), and telediastolic (Vtd) velocities.
• Calculated absolute (F) and normalized (FN) fluxes, and resistance index (IR).

Main Results:

• All measured Doppler parameters (TAV, Vts, Vtd, F, FN, IR) were statistically significant indicators of FAV functionality.
• Recommended parameters for optimal functionality: FN > 2000 ml/min/cm², IR < 0.05, TAV > 50 cm/s, Vtd > 35 cm/s.

Conclusions:

• US-Doppler is a valuable noninvasive method for assessing FAV capacity and functionality.
• Specific Doppler parameters provide reliable metrics for determining FAV suitability for hemodialysis.