A review of calcium antagonists and atherosclerosis.

Many detailed studies have demonstrated that calcium antagonists can suppress development of diet-induced atherosclerosis in the thoracic aorta of animals. A number of possible mechanisms have been proposed based on in vitro work, but the exact mechanism remains unclear. Alteration of serum lipid levels and blood pressure does not appear to be the common pathway. Differing effects between calcium antagonists of different classes indicate that the voltage-dependent calcium channel-blocking action common to all calcium antagonists is not the sole mechanism. Preliminary results of several major quantitative angiographic studies in human coronary artery disease have recently become available and indicate that calcium antagonists are able to retard the progression of existing lesions in humans also. There is also evidence that calcium antagonists may prevent the development of new lesions and, in some cases, induce lesion regression. Longer follow-up and further trials are required to assess the appropriateness of widespread clinical application of these agents in coronary artery disease, to determine the optimal timing for their introduction, and to define their mechanism of action in influencing the natural history of atherosclerosis.