Endothelial Function and Early Atherosclerotic Changes

Endothelial dysfunction, including impaired vasomotor disturbance, abnormal coagulation, and increased vascular proliferation, is closely associated with the development of atherosclerosis and precedes the clinical manifestations of atherosclerosis. The impairment of endothelium-dependent vasodilation, which is chiefly attributed to decreased endothelial nitric oxide (NO) bioavailability, represents the functional characteristic of endothelial dysfunction and a early key step in the occurrence of atherosclerotic complications. An impairment of endothelial vasodilation is attributed to decreased NO production, deficiency of substrate or cofactor availability, and increased NO inactivation, and is not confined to a certain artery such as the coronary artery, but rather represents a systemic disorder that also affects peripheral vascular beds. Noninvasive endothelial function tests using extremities are a new popular method for the detection of endothelial NO bioavailability. The assessment of endothelial function detected before established atherosclerosis may be a more important risk factor to predict future atherosclerotic diseases compared with conventional risk factors such as hypertension and hyperlipidemia.