An electrical shock is delivered to the heart to convert an abnormal heart rhythm back to a normal rhythm. Most elective or "non-emergency" cardioversions are performed to treat atrial fibrillation or atrial flutter, benign heart rhythm disturbances of the heart. Cardioversion may be used in emergency situations to correct a rapid abnormal rhythm associated with faintness, low blood pressure, chest pain, difficulty breathing, or loss of consciousness.
Cardioversion can be "chemical" or "electrical". Chemical cardioversion refers to the use of anti-arrhythmic medications to restore the heart's normal rhythm. Your doctor may decide to start your anti-arrhythmic medication as an outpatient, or he or she may choose to admit you to the hospital to give you an intravenous (IV) or oral anti-arrhythmic medication while your heart rhythm is closely observed.
Electrical cardioversion is a procedure where perfectly-timed electrical shock is delivered through the chest wall to the heart through special electrodes or paddles that are applied to the skin of the chest and back. This split second interruption of the abnormal beat allows the heart's electrical system to regain control and restore a normal heartbeat.