Automated Border Detection for Assessing the Mechanical Properties of the Carotid Arteries: Comparison with Carotid Intima–Media Thickness

Background

Although carotid intima–media thickness (CIMT) assesses the structural properties of the carotid artery, it does not assess the mechanical properties of the vessel.

Methods

The carotid arteries of 71 adult patients were evaluated with CIMT, and automated border detection computed vessel stiffness, compliance, elasticity, and distensibility.

Results

CIMT and mechanical properties were differentially affected by traditional cardiac risk factors, with age dominating for CIMT, and age, diabetes, and smoking dominating for mechanical variables. There was a moderate linear correlation between CIMT and the distensibility coefficient (r = −0.54), but there were weak associations with other parameters of dynamic vessel function. When patients were separated into risk groups, the mechanical vascular parameters' classification frequently differed from the CIMT classification. This was particularly notable for patients with intermediate CIMT values, who were reclassified as low or high risk by mechanical parameters 45% of the time.

Conclusion

We found that it is feasible to assess the cross-sectional area of the carotid artery using automatic border detection, which allows a novel method of determining carotid mechanical properties. These functional characteristics are often discordant with CIMT, suggesting that mechanical properties may be an important adjunct to the CIMT when evaluating the carotid artery.

Keywords: Automated border detection, Carotid arteries, Carotid intima–media thickness, Echocardiography

Abbreviations: ABD, Automated border detection, Ad, End-diastolic area, As, End-systolic area, AQ, Acoustic quanification, CIMT, Carotid intima-media thickness, CSC, Cross-sectional compliance, DC, Distensibility coefficient, Dd, End-diastolic dimension, Ds, End-systolic dimension, EM, Elastic modulus