Arterial Stiffness in Elastic and Muscular Arteries: Measurement using ARTSENS Pen

Various arterial segments in the macrovasculature exhibit heterogeneity in terms of the structural and functional properties. Owing to the difference in the structural composition, there exists a stiffness gradient from central to peripheral arteries. The loss in this gradient is multifactorial, such as aging, plaque formation, degradation of vessel elastin etcetera. This is a proven pathophysiological basis for cardiovascular risks, chronic kidney diseases, and end-organ damage. Clinical studies have reported the importance of measuring the local stiffness from peripheral arteries along with the central arteries. However, there is an unmet need for easy-to-use, portable, and non-expert operable tool for performing the stiffness measurements from individual target arteries. In this work, we have demonstrated the feasibility of using a highly compact image-free ultrasound device, ARTSENS® Pen, for measuring the central (carotid) and peripheral (brachial) arterial stiffness together. An in-vivo study was performed on a cohort of 19 subjects within the age group of 20 – 55 years for the same. The diameter and stiffness measurements performed in the recruited subjects were repeatable for both the arteries with a beat-to-beat coefficient of variation smaller than 5.3% and 7.5% respectively. The group average stiffness index for the brachial artery was observed to be higher than that of the carotid artery. The slope of the relationship between the carotid β stiffness versus the age of the subjects was higher compared to brachial, indicating higher stiffness progression rate for the carotid artery. A gradient reversal for the recruited population was observed for the older population. These observations were consistent with the theory and the earlier reported studies. In conclusion, the proposed technology provides a potential easy-to-use compact tool for performing fully automated stiffness measurements from multiple heterogeneous arterial sites.