Definition Description: Amiodarone is an antiarrhythmic used to treat different types of tachyarrhythmias. Electrophysiology: Class III antiarrhythmic (prolongs repolarization); lengthens cardiac action potential, negative chronotropic effect in nodal tissues, blocks myocardial K and Ca channels –> slows conduction speed in SA node, causes prolongation of refractory period. Hemodynamic effects: IV amiodarone has a negative inotropic […]