NCIt definition : An iodine-rich benzofuran derivative with antiarrhythmic and vasodilatory activities.
As a class III antiarrhythmic agent, amiodarone blocks the myocardial calcium, potassium
and sodium channels in cardiac tissue, resulting in prolongation of the cardiac action
potential and refractory period. In addition, this agent inhibits alpha- and beta-adrenergic
receptors, resulting in a reduction in sympathetic stimulation of the heart, a negative
chronotropic effect, and a decrease in myocardial oxygen demands. Amiodarone may cause
vasodilation by stimulation of the release of nitric oxide and cyclooxygenase-dependent
relaxing endothelial factors.;