Clinical importance of endothelial function in arteriosclerosis and ischemic heart disease.

The vascular endothelium is a dynamic endocrine organ that regulates vascular tone, local homeostasis, and the fibro-inflammatory-proliferative process. These responses are mediated by various substances released from the endothelium in response to physiologic stimuli, including prostacyclin, endothelin and, most importantly, nitric oxide (NO). NO mediates vasodilation and inhibits platelet aggregation, thrombus formation, expression of adhesion molecules and chemokines for leukocytes, and oxidative stress. It also attenuates growth and proliferation of vascular smooth muscle cells. Risk factors for atherosclerosis, such as hypercholesterolemia, hypertension, diabetes and cigarette smoking, impair endothelial function, which leads to atherosclerosis and results in ischemic manifestations such as acute coronary syndrome and stroke. Thus, therapeutic intervention aimed at increasing NO bioavailability by statins or angiotensin-converting enzyme inhibitors might improve patient prognosis. Vascular endothelial function is an important and clinically relevant therapeutic target for cardiovascular disease.