Ultrasonographic Measurement of Common Carotid Artery Wall Pulse Dynamics and Longitudinal Motion – Method Validation and a Novel Parameter Ratio

Abstract

Objectives

The enormous burden that cardiovascular diseases put on individuals and societies warrants reliable biomarkers of disease risk to optimize disease prevention. We studied longitudinal movement (LMov) in arterial walls using ultrasound of the common carotid artery (CCA). We believe that LMov could be a sensitive biomarker of cardiovascular health and in this study, we evaluate the intra-observer repeatability and inter-observer precision of our method. We also present a novel parameter ratio.

Method

Four independent researchers, called “observers”, analyzed CINE-loops of two separate ultrasound recordings of the CCA in 20 healthy individuals using an in-house developed program (ARTIC) based on MATLAB. Vessel wall displacement was measured in two dimensions and results between repeated measurements for one research subject and between observers were compared. We also present and evaluate a novel parameter ratio, the notch ratio (NR) which by combining velocities of phases B and X reduces variability and improves comparability of LMov analysis in late systole.

Results

Most LMov parameters showed good repeatability with coefficient of variation (CV) values 10%–26%. CV values for radial and IMT measures were excellent between 1% and 7%. Intra-class correlation coefficients (ICC) for inter-observer precision of single measures showed excellent values ICC > 0.9. NR improved LMov analysis in late systole and showed homogenous values of 1.36–1.45 between observers and good CV values of 9%–20%.

Conclusion

We demonstrate good intra-observer repeatability and excellent inter-observer precision of LMov analysis using ARTIC. NR displays similar consistency. This promotes further research on larger study populations using the same method focusing on the possible pathophysiological link between LMov and cardiovascular disease.