Speckle Tracking of Common Carotid Artery: A New Method for the Evaluation of Mechanical Vascular Function of Atherosclerosis

Abstract

As cardiovascular death remains major cause of death worldwide, there are growing needs for risk evaluation for cardiovascular event. Arterial stiffness, which refers to the rigidity of arterial wall, increases in the elderly person as well as patients with atherosclerotic disease. Based on the belief that increased vascular stiffness precedes atherosclerotic vascular event, there were attempt to measure vascular stiffness. In this regard, carotid-femoral pulse wave velocity (PWV) using tonometry has been proven to be simple, noninvasive measurement of vascular stiffness, as it is inversely related with vascular compliance. Stiff and rigid vessel would transfer pulse wave faster and PWV be higher. On the other hands, carotid intima-media thickness (CIMT) using ultrasound is well correlated with cardiovascular risk and is commonly used as surrogate marker of systemic atherosclerosis. Current advance in automated imaging analysis made it much easier to obtain CIMT in daily clinic and reproducibility of the measurement got even better. Another approach to obtain information about vascular stiffness was ultrasound-based measurement of regional mechanical properties of arterial wall. This method includes the measurement of changes in the dimension of an artery generated by each pulse pressure. From the pressure and diameter measurement, variables regarding vascular stiffness such as distensibility, compliance, elastic modulus index and beta stiffness index can be calculated. More recently, technical advance in speckle tracking method, which originally used for the measurement of ventricular pISSN 1975-4612/ eISSN 2005-9655 Copyright © 2016 Korean Society of Echocardiography www.kse-jcu.org http://dx.doi.org/10.4250/jcu.2016.24.3.195