An Increase of Maximal Intima-Media Thickness in Bilateral Carotid Arteries Strongly Suggests the Existence of Coronary Stenosis in Japanese Type 2 Diabetic Patients

An association of an increase of maximal intima-media thickness (IMT) of carotid artery to coronary artery stenosis was evaluated in Japanese type 2 diabetic (T2DM) out-patients without any typical cardiac symptoms or history. Maximal IMT from common carotid artery to internal carotid artery was measured by ultrasonography in T2DM outpatients without any symptoms or history of coronary artery disease (CAD). The patients with a significant increase of maximal IMT over 1.5 mm were consulted to cardiologists, and the existence of coronary artery stenosis was evaluated by multiple detector- row computed tomography (MDCT). The patients with coronary artery stenosis suspected by MDCT were additionally the existence of CAD by coronary angiography. From April 2013 to December 2014, we found 17 patients with an increase of maximal IMT in bilateral carotid arteries and 9 patients with an increase of maximal IMT in unilateral carotid artery in T2DM outpatients. The patients with a significant increase of maximal IMT in bilateral carotid arteries had higher of coronary artery stenosis by coronary angiography (76.5 %) than those in unilateral carotid artery (11.1%).The 47.1 % of the patients with an increase of maximal IMT in bilateral carotid arteries was judged to need percutaneous coronary intervention therapy. In conclusion, a significant increase of maximal IMT in bilateral carotid artery strongly suggests existence of coronary artery stenosis in Japanese T2DM patients. Screening of maximal IMT in bilateral carotid arteries should be beneficial for the detection of silent ischemia in coronary artery.