SUMMARYThe correlation of peripheral endothelial dysfunction and intima-media thickness (IMT) in patients with suspected coronary artery disease (CAD) has been unclear. Inflammation and thrombosis may play a role at early stages of atherosclerosis. Thus, early atherosclerosis was noninvasively examined morphologically by IMT of carotid arteries, and functionally by flow mediated dilation (FMD) of brachial arteries in patients who were suspected of CAD and had undergone coronary angiography. Plasma antigen levels of tumor necrosis factor (TNF)-α and interleukin (IL)-6, representative atherogenic cytokines, tissue factor (TF) and tissue factor pathway inhibitor (TFPI), markers of coagulation, and plasma activity level of plasminogen activator inhibitor type-1 (PAI-1), a marker of defective fibrinolysis, were measured. Patients with coronary atherosclerosis in one or more vessels with lesion ≥50% had significantly reduced FMD compared with those with angiographically normal coronary arteries. Carotid artery IMT increased significantly only in patients with advanced coronary atherosclerosis in one or more vessels with lesion ≥90%. Plasma antigen levels of IL-6 were significantly increased in patients with reduced FMD (<5%) compared to those in patients with FMD between 10 and 15%. Plasma antigen levels of TF, total and free TFPI, and PAI-1 activity tended to increase with a reduction in FMD. Thus, (1) FMD was reduced at early stages of CAD while IMT was increased in advanced CAD, and (2) inflammation and thrombosis may play a role in the early stages of the atherosclerotic process. (Jpn Heart J 2002; 43: 117-125)