Novel Peripheral Perfusion Dynamics Indices for Detecting and Grading Arterial Stenosis

Area of Science:

• Vascular Medicine
• Biomedical Engineering
• Diagnostic Imaging

Background:

• Peripheral artery disease (PAD) significantly impacts health, particularly in the elderly and diabetic populations.
• Accurate, noninvasive methods for detecting peripheral arterial stenosis are crucial for timely intervention.
• Existing diagnostic tools may have limitations in differentiating stenosis from arterial hardening.

Purpose of the Study:

• To test the hypothesis that leg perfusion dynamics change characteristically with arterial stenosis.
• To evaluate impedance plethysmography (IPG) for noninvasive detection and grading of peripheral arterial stenosis.
• To identify novel indices from IPG signals indicative of stenosis severity.

Main Methods:

• Healthy volunteers (n=30) underwent induced arterial stenosis using thigh cuff compressions (45 and 90 mmHg).
• Leg perfusion dynamics were measured continuously using impedance plethysmography (IPG).
• Key parameters including time to peak perfusion and slow phase duration were analyzed.

Main Results:

• Arterial compression prolonged the slow phase duration (SPd) of the perfusion upstroke.
• The SPd was proportional to the degree of emulated arterial stenosis.
• The method achieved high sensitivity (>93%) and specificity (100%) in detecting stenosis.

Conclusions:

• Novel IPG-derived indices, specifically SPd, accurately identify and grade arterial stenosis.
• This noninvasive technique shows promise for early PAD diagnosis.
• The method may help differentiate focal arterial stenosis from diffuse arterial hardening.