[A nomogram of duplex ultrasound quantification of peripheral arterial stenoses. Studies of the cardiovascular model and in angiography patients]

Abstract

Background and methods: Blood flow velocity measurements were performed with duplex ultrasound in vitro (flow phantom) and in 62 patients who underwent angiography due to peripheral vascular disease.

Results: Intrastenotic peak systolic velocity (PSV) divided by proximally recorded PSV (peak velocity ratio, PVR) exhibited a strong correlation with percent diameter reduction: r2 = 0.86; N = 106 stenoses. A PVR value > or = 2.4 indicated a more than 50% stenosis with a sensitivity of 87% and a specificity of 94%. Calculation of PVR may normalize for patient variation and allow noninvasive quantification of lumen narrowing with high sensitivity and specificity. The intraobserver variability (95% CI) of stenosis quantification using PVR values was 10%. A nomogram simplifies estimation of lumen narrowing after measurement of intrastenotic and proximal PSV values.

Conclusion: Quantification of peripheral artery stenoses can be performed easily and noninvasively with duplex ultrasound using the peak velocity ratio (PVR).