Cardioversion Versus Catheter Ablation

June 22, 2022

If you suffer from an arrhythmia like Afib and specifically a fast heartbeat known as tachycardia, you may have seen information on two very different ways to get the heart back into sinus or normal rhythm. First, we’d like to give you an overview of each procedure; then, we will discuss when these procedures can be used to maximize effectiveness.


Cardioversion involves shocking the heart back into its normal rhythm. It’s a straightforward procedure that EMTs can perform during an emergency but is more often scheduled with your electrophysiologist. Pads are placed on the chest, and an electric shock is delivered to the heart to reset its electrical signals.

 While electrical cardioversion uses shocks to bring the heart back into normal rhythm, there are also medications that, in theory, can do the same thing. While some patients may benefit from chemical cardioversion (thus avoiding sedation and electric shock), electrical cardioversion is typically much more successful.

How Does Cardioversion Differ from Defibrillation?

While the principle of shocking the heart is the same, cardioversion delivers a milder shock. Defibrillation is always used during emergencies where the patient is at significant risk for sudden cardiac death. Cardioversion is used to shock the heart out of an arrhythmia.

Cardiac Catheter Ablation

On the other hand, cardiac catheter ablation is a much more involved procedure that requires anywhere from 2 to 4 hours. During this procedure, a catheter is threaded up a vein in the groin to the heart. The heat generated by RF waves or cold generated by cryo-ablation is delivered to the specific areas of the heart, neutralizing the heart tissue causing the arrhythmia.

When Would Either Be Used?

Cardioversion may be used as a first step intervention to shock the heart back into normal rhythm. This is typically performed early in the continuum of patient care with the hope that an arrhythmia is a one-off event. However, if the patient begins to experience more frequent arrhythmia episodes or if it is clear that the arrhythmia is here to stay, cardiac catheter ablation is often a more suitable option. Why? If there is an underlying cause of the arrhythmia, cardioversions do not address it. It simply brings the heart back to normal. On the other hand, cardiac catheter ablation targets the errant electrical signals of the heart by destroying the tissue that creates them. While an ablation is more involved, it can significantly reduce the likelihood of future Afib or other arrhythmia episodes.

Most importantly, if you are experiencing occasional or persistent atrial fibrillation, it is important to visit an electrophysiologist like Dr. Banker to understand the next steps in the treatment process. For some, lifestyle changes and medication may be sufficient to control arrhythmia. For others, however, cardiac catheter ablation may be a good option for controlling the arrhythmic events and reducing dependence on medication.