External Cardioversions

If you have been diagnosed with rapid and irregular heartbeat, known as atrial fibrillation or atrial flutter, you may benefit from cardioversion. This procedure delivers shocks of measured electricity to heart that stabilizes the heart rate. This procedure can also be used in patients with ventricular tachycardia, an extremely fast and life-threatening rhythm in the lower chambers of the heart.


Cardioversion helps restore your heart to a normal state, pumping blood at a consistent rate and delivering it throughout the body. Symptoms of irregular heart rhythm include:

  • Fluttering in the chest
  • Shortness of breath – with or without exercise
  • Chest pain or slight discomfort
  • Dizziness
  • Fainting or fatigue.

An irregular heartbeat can, over time, result in a heart attack or stroke, so it is important to bring the rhythm to a normal rate.

Before a Cardioversion

Before the procedure begins, you will be hooked up to a cardioverter, which monitors your heart. This will show if your heart rate is too slow or too fast, giving your doctor information on how to pace your heart rate. Your heart’s electrical activity, blood pressure and oxygen levels will also be monitored. An intravenous (IV) line will be placed in your arm and will deliver the drugs to put you to sleep to perform the procedure.

Once you are fully sedated, your doctor will use the cardioverter, also called a defibrillator, to “shock” your heart and restore a normal rhythm. It may take a few times to return your heart rate normal rhythm. In some cases, your doctor may have to perform a transesophageal echocardiogram (TEE) to get a clear view of the blood flow in your heart.

While the procedure only takes a few minutes, plan to stay at WakeMed for a few hours to recover. You may feel some soreness in your chest from where the cardioversion pads were placed to deliver the electrical shocks. Hydrocortisone cream will provide relief from the itching or discomfort.

Since you will be sedated for the cardioversion, plan on taking it easy when you go home. You can return to normal activities, as advised by your doctor, on the following day.

How to Prepare for a Cardioversion

  • Do not eat or drink after midnight on the evening before the procedure.
  • Take your regular medications, but only have a small amount of water to take pills.
  • If you take blood thinners or have diabetes, talk with your doctor about any special instructions.

Make sure that you bring a driver with you because you cannot drive home. You will be able to resume driving and normal activities on the day after the cardioversion.

Your doctor will talk with you about the results of the cardioversion and let you know how you can continue to care for your heart health.