Antiatherogenic properties of calcium antagonists.

Atherosclerosis results from multiple factors, and involves several mechanisms including endothelial monocyte and smooth muscle cell changes, cholesterol accumulation, lumen stenosis, necrosis, mineralization, plaque hemorrhage, rupture, and thromboembolism. Calcium antagonists have been shown in hypercholesterolemic animal models to reduce atherosclerosis. This effect cannot be explained on the basis of changes in blood pressure, therefore suggesting that calcium channel antagonists have a direct effect on arterial wall processes associated with plaque evolution. The antiatherosclerosis properties of calcium antagonists have been tested in human subjects and suggest that these compounds inhibit new lesion development. Recent developments in B-mode ultrasonography allow investigators to detect and monitor atherosclerosis noninvasively. This method is being used in several trials within the U.S. and Europe to evaluate treatment effects on carotid atherosclerosis. Carotid artery disease is associated with transient ischemic attacks, ischemic cerebral infarction, and with risk for coronary artery disease. B-mode ultrasonography is a powerful method for monitoring atherosclerosis progression. The combination of this technology with calcium antagonist treatment will allow evaluation of the efficacy of intervention on the arterial wall during the asymptomatic stages of atherosclerosis evolution.