Dronedarone

Dronedarone is a non-iodinated analogue of amiodarone with multiple ion channel-blocking properties. Dronedarone inhibits potassium channels, including the delayed rectifier potassium currents IKr and IKs in cardiac muscle, thereby prolonging the cardiac action potential and effective refractory period (ERP), which reduces the likelihood of abnormal reentrant conduction. Dronedarone also inhibits sodium channels, slowing phase 0 depolarization and reducing conduction velocity, which helps stabilize the myocardial membrane. In addition, dronedarone inhibits L-type calcium channels, reducing conduction through the sinoatrial node and atrioventricular node.