What is Cardioversion?

Cardioversion refers to the process of restoring the hearts normal rhythm by applying a controlled electric shock to the exterior of the chest. Cardioversion is successful in more than 75% of people who have the procedure. However, fast or irregular heartbeats can occur again. Over time, you may need to have a repeat cardioversion.

Why do I need a Cardioversion?

Your doctor has probably told you that you have an arrhythmia (abnormal heart rhythm) called atrial fibrillation or atrial flutter (AF) and that you are in need of a procedure called a Cardioversion.

AF is an irregular heart rhythm. While AF is not immediately life threatening, it can lead to serious medical problems. AF can allow blood to pool within the heart and form clots. These clots can travel in the bloodstream and cause a Stroke or Heart Attack. AF can also cause significant symptoms including dizziness, fainting, palpitations, fatigue and chest discomfort. Cardioversion treats AF and the associated problems by restoring your hearts normal rhythm.

What to expect before the procedure

Due to the risk of clot formation with irregular heart rhythms, your doctor may prescribe blood thinning medicine to prevent them. You may start taking this medicine several weeks before the procedure and continue it for several months afterwards.

  • Do not eat or drink anything 6 hours prior to your procedure.
  • Men with hairy chests may require shaving in the areas where the patches used during the procedure will be placed. 
  • You will be asked to sign a form consenting to the procedure.

Your doctor will visit you to explain the procedure and answer any questions you may have.

During the Procedure

An IV cannula will be placed in your arm, so that you can be given medications to help you relax/sleep during the procedure.
You will be connected to our monitors so that we can watch your heart rhythm, blood pressure, breathing and oxygen levels throughout the procedure.

Two large sticky patches will be applied to your chest. These will be attached to the defibrillator, which is the machine that delivers the shock. You will not feel a shock when the energy flows through your heart because you will be asleep. This energy flow will attempt to restore your hearts normal rhythm.

The procedure lasts approximately 10 minutes.

What are the risks?

In rare cases, cardioversion can cause life-threatening arrhythmias. These irregular heart rhythms will occur within minutes of the procedure while you are still being monitored. Since they would be treated immediately with shocks or medicine, they usually do not cause serious problems.

Rarely, cardioversion can cause stroke or other complications if blood clots in the heart travel elsewhere in the body. The risk of this happening is small. Your doctor will discuss the risks with you.

Recovery and Discharge

  • You will remain rested in bed until you have fully recovered from the medications used to make you sleep.
  • You will be given oxygen via a mask or nasal prongs until you can maintain your own oxygen levels.
  • The nurses will continue to monitor your heart rhythm, blood pressure, breathing and oxygen levels regularly.
  • You can eat and drink once you are fully awake and alert.
  • You may have slight redness and discomfort to your chest from the patches used to deliver the shock. This may last for a few days after the procedure.

If all goes well, you will be discharged home after 4 hours. Make sure that you have arranged for someone to take you home after the procedure. Due to the medication given during the procedure, you will not be allowed to drive or use heavy machinery for 24 hours following your cardioversion.

If you have further questions regarding this procedure, please ask your nurse or doctor for clarification.