Abstract
Background: Carotid arteries have been used as “windows” to or indicator sites for cerebral and coronary arteriosclerosis. However, there are many cases of cerebral or myocardial infarction without atherosclerosis in carotid arteries. Purpose: To find a new “window” and to determine whether subclavian and carotid arterial intima-media thickness (IMT) predicts cerebral infarction and coronary events. Subjects and Method: Maximal IMT of the right subclavian artery (S-max) and maximal IMT of carotid arteries (C-max) were measured by high-resolution (10 MHz) ultrasonography in 628 consecutive patients (26 patients with a history of cerebral infarction or coronary events and 602 patients without events) at Majima Digestive Organ Clinic. LDL, HDL, TG, taste in food, diabetes, and hypertension were examined in the patients without events. Taking the cases with events into consideration, the ultrasonographic findings in all cases were classified into five categories. Results: S-max was detected in 610 (97.1%) of 628 patients. The degree of thickening of S-max was correlated with LDL and TG levels, taste in food (meats, sweets, vegetables), and hypertension in the elderly (≥60 years old). The degree of thickening of C-max was correlated with LDL and HDL levels, taste in food (meats), and hypertension in the elderly (≥60 years old). The event history rate in the five categories was as follows: Level 0: 0.0% (0/182); Level 1: 1.2% (2/164); Level 2: 2.0% (2/100); Level 3: 11.4% (9/79); Level 4: 14.1% (12/85). Conclusions: S-max is a new clear “window” for the quantitation and follow-up of preclinical atherosclerosis. The categories employing the combination of S-max and C-max measurements are very useful for determining the risk levels of cerebral infarction and coronary events.
