Oscillometric pulse wave analysis for detecting low flow arteriovenous fistula

Area of Science:

• Vascular access monitoring
• Hemodialysis technology
• Cardiovascular diagnostics

Background:

• Arteriovenous fistula (AVF) function is crucial for hemodialysis efficacy.
• Pulse wave analysis (PWA) shows potential for non-invasive fistula assessment.
• Need for convenient methods to detect reduced fistula flow (<500 ml/min).

Purpose of the Study:

• To prospectively evaluate oscillometric devices for AVF function assessment.
• To determine the applicability of PWA in a real-world clinical setting.
• To identify PWA parameters capable of detecting low fistula flow.

Main Methods:

• Prospective study involving 53 hemodialysis patients with native AV fistulas.
• Pulse waves recorded using the vicorder® device at the brachial artery.
• Analysis of pulse wave parameters: Slope2, Slope∑, and Amplitude (AMP); fistula flow measured by duplex sonography.

Main Results:

• Oscillometric parameters differentiated between fistula and non-fistula arm measurements with significant sensitivity and specificity.
• ROC analysis indicated that AMP (AUC=0.775) and Slope∑ (AUC=0.732) could detect low fistula flow.
• AMP demonstrated the highest diagnostic accuracy, with optimal cut-off values yielding 93% sensitivity and 78% specificity for detecting low flow.

Conclusions:

• Functional surveillance of AV fistulas using oscillometry is a promising clinical tool.
• The Amplitude (AMP) parameter derived from PWA offers the highest diagnostic accuracy for identifying reduced fistula flow.
• Oscillometric devices provide a convenient and effective method for monitoring AV fistula function in hemodialysis.