NCIt definition : The hydrochloride salt of 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.;
Alternative definition : NCI-GLOSS: A drug used to treat certain types of abnormal heart rhythms that have
not gotten better with other drugs. Amiodarone hydrochloride affects the electrical
activity of the heart. It is a type of antiarrhythmic agent.;