[Investigation of atherosclerosis using carotid ultrasonography]

Carotid ultrasonography is useful for patients in the early stage of atherosclerosis or with manifest vascular disease. We can assess the intima-media thickness (IMT), stenosis, and also elasticity of the carotid artery noninvasively. IMT is well-known as a strong predictor of future vascular events and a surrogate marker of atherosclerosis. We examined 353 consecutive subjects (coronary artery disease: n=92, cerebral vascular disease: n=62, peripheral arterial disease: n=104), regarding whether the accumulation of vascular diseases affects the IMT. The maximum IMT of the common carotid artery expanded with increasing numbers of vascular diseases (no vascular disease, 1.10 +/- 0.51; one vascular disease, 1.38 +/- 0.63; two vascular diseases, 1.69 +/- 0.65; three vascular diseases, 2.01 +/- 0.67 mm; p < 0.01, no vs. one vascular disease, one vs. two vascular diseases). The accumulation of vascular diseases, independent of the types of vascular lesion, accelerated carotid atherosclerosis. The stiffness parameter beta of the carotid artery was related to the brachial-to-ankle pulse wave velocity(baPWV) (n=38, r = 0.81, p < 0.0001). Stiffness parameter beta (10.95 +/- 2.8) and baPWV (1,549 +/- 179 cm/s) in the metabolic syndrome (MetS) group (n=18) was higher than in the preliminary MetS (n=12, 8.82 +/- 1.69, 1417 +/- 148 cm/s) and control (n=8, 7.90 +/- 1.78, 1357 +/- 171 cm/s) groups. The mean IMT of the common carotid artery was not different between the MetS and preliminary MetS groups. Morphological and functional changes in atherosclerosis can be evaluated employing carotid ultrasonography.