If your heart is irregular or is beating too fast as might happen in atrial fibrillation, cardioversion is a way to restoring normal rhythm. There are two kinds of cardioversion. Your doctor may give you one or more medicines to bring back your regular heartbeat. This is called pharmacologic (chemical) cardioversion. Doctors also restore regular rhythms by sending an electrical shock to the heart. This is called electrical cardioversion. If you have electrical cardioversion, you’ll get medicine to put you to sleep so you don’t feel the shock.

In atrial fibrillation, very fast, irregular electrical signals (fibrillation) move through both of the upper chambers of your heart (the atria). This can make your heartbeat to be fast and irregular. Some people who have atrial fibrillation don’t notice any change in the way they feel. But others may feel very fast heartbeat or palpitations, shortness of breath, feeling tired or weak.

Cardioversion can also treat other kinds of abnormal heartbeats, including atrial flutter , atrial tachycardia and ventricular tachycardia . Cardioversion or defibrillation is also used in emergency situations for people who suffer sudden life threatening heart arrhythmias.


If you have atrial fibrillation, blood clots can form in your heart’s left upper chamber. Cardioversion may cause a loose a blood clot in your left atrium to move along the circulation. If the clot travels to the brain, it can cause a stroke . To avoid this, our physician may give you a blood thinner to make your blood less likely to form blood clots. You will need to take the blood thinner, uninterrupted, for 3 to 4 weeks before the procedure. Transesophageal echocardiography (TEE) may be used to check for the presence of blood clots before this procedure.

If you have an electrical cardioversion, the skin on your chest or back where the patches or paddles are applied may become irritated. Your doctor can tell you about creams to make your skin feel better.

Cardioversions don’t always bring back normal heart rhythms. If the abnormal heart rhythm returns, your physician will have to discuss other treatment options.