What is Cardioversion?

Cardioversion is a procedure conducted to return an abnormal heartbeat back to its normal pattern. They are used to correct arrhythmias (irregular heartbeats). Cardioversions can be done with defibrillators, delivering an electric shock, or with certain pharmaceutical drugs. There are two methods of cardioversion, known as electrical cardioversion and pharmacologic/chemical cardioversion.

People may have a cardioversion performed if they experience atrial fibrillation, atrial flutter, tachycardia, bradycardia, or other arrhythmias. Some symptoms that accompany these conditions are drastic changes in the speed of the heartbeat, shortness of breath, and fatigue.


Cardioversion is similar to defibrillation in that they both use electric shocks to reset the heart, however, defibrillation has stronger shocks as it is used in situations where the arrhythmia is life-threatening


What are the risks of Cardioversion? Cardioversions are extremely effective and successful but there may be a few risks associated with the procedure, such as blood clots and skin irritation. Most of the possible risks are accounted for and preventative measures are taken to minimize them from happening.

For example, in patients with atrial fibrillation, blood clots can form in the heart's left atrium, which could be knocked loose by cardioversion. Doctors often use medicines, like warfarin, for a few weeks prior to the procedure to make the blood less likely to form clots. A test called a transesophageal echocardiogram (TEE) is used to check for blood clots, to avoid the risk of complications from blood clots.

How do I prepare? The day of the procedure, have someone available to drive you to and from your appointment.

  • Avoid operating any machinery for the rest of the day following the completion of the cardioversion.
  • Do not eat or drink for at least 8 hours before your appointment
  • Take your medications as prescribed the morning of your procedure unless otherwise stated by your physician
  • Bring a list of medications, including over-the-counter medicines, vitamins, and supplements
  • Leave ALL jewelry at home
  • If you are undergoing an electrical cardioversion, refrain from putting on any lotions, powders, creams, or ointments on your chest and back for 24 hours before your procedure

These can cause issues with the paddles used

What happens during the Electrical Cardioversion? A physician places an IV in your arm to provide a sedative. Soft electrodes are placed on your chest and possibly back. These areas may need to be shaven to help the electrodes stick better. The electrodes are attached to the cardioversion where the shocks are generated from. The shocks last less than a second and briefly resets the heart rhythm. For some, they may need more than one shock. This is determined by the team that closely monitors your heart rhythm. The procedure takes about a few minutes to complete. Once the procedure is over, you will be woken up.

What happens after? Once the cardioversion is over, your healthcare team monitors you closely for another hour or so to see if any complications arise. Your doctor will then speak to you about whether or not additional medications will be necessary to maintain the normal rhythm. There may be some redness and irritation where the electrodes were placed. If this occurs, contact your healthcare provider to ask about ointments or creams that can help. If there are any questions that come up after the completion of the cardioversion, call your doctor for clarification.