Cardioversion is a treatment to restore a normal heartbeat when your heart is beating too fast or with an irregular rhythm. It's often used to treat atrial fibrillation, the most common kind of irregular beat.

There are two types of cardioversion. Chemical cardioversion uses medications that can relax an overactive heart. Electrical cardioversion uses one or more quick electric shocks to the heart. The shock is delivered through electrodes attached to the chest. Sometimes one type of cardioversion won't work for a patient but the other type succeeds.

While the effect of a cardioversion lasts for most patients, some see their abnormal heartbeat return days or weeks after treatment. Repeat cardioversions can be performed. If the rhythm still doesn't stabilize, patients may be referred for catheter ablation, a procedure that destroys the heart tissue causing the irregularity.