Association Between Atherosclerosis in Carotid Artery and Elastic Modulus of Brachial Artery

Common carotid arterial stiffness can be assessed during carotid arterial ultrasonography, but its association with brachial stiffness, a well-defined cardiovascular risk factor, has not been clarified. The aim of this study was to examine the relationship between common carotid artery and brachial artery stiffness. The static pressure-strain elastic modulus of the common carotid and brachial arteries were evaluated in 40 men with 15 healthy carotids, 15 mild carotid stenoses, and 10 severe carotid stenoses, by B-mode and Doppler ultrasonography. The local elastic modulus was estimated by the measurement of the arterial strain; the static pressure was also measured based on the peak-systolic and end-diastolic velocity in each artery. The elastic modulus of the right common carotid artery (RCCA) and right brachial artery (RBA) increased linearly with the growth of atherosclerosis from 1772±566 Pa and 2639±1096 Pa for the normal subjects to 6168±1026 Pa and 5587±1592 Pa for the severe stenosis group, respectively. In the three groups; healthy, mild stenosis, and severe stenosis; there was a significant difference in the elastic modulus of the right common carotid artery between the groups and also for the right brachial artery, separately (p-value<0.05). The Pearson correlation analysis showed a significant correlation between the elastic modulus of the right common carotid artery and the elastic modulus of the right brachial artery. The brachial artery elastic modulus is associated with the common carotid elastic modulus. This study showed that atherosclerosis was a generalized process that might involve the entire vasculature. An evaluation of the elastic modulus of the RBA, however, showed that there were fundamental differences in the dynamic behavior of the brachial artery when compared to elastic arteries, such as the common carotid artery.