Electric shock, how does it work?


  • In the case of atrial fibrillation, the patient may be offered electrical cardioversion, in which an electrical current is briefly passed through the patient’s chest to resynchronize the heart cells and restore a regular heart rhythm.
  • This treatment is 90% effective but requires finding the factors causing the arrhythmia to prevent it from coming back.

Heart disease that affects up to 750,000 French people, atrial fibrillation, formerly known as atrial fibrillation, is characterized by an acceleration and an irregular heartbeat. This irregular sinus rhythm can lead to the formation of clots in the atria of the heart, which can then travel from the heart to the brain and cause a stroke. Atrial fibrillation can also cause the lower chamber of the heart to weaken, leading to fluid buildup or heart failure.

Among the treatments used for atrial fibrillation is electrical cardioversion. Unlike defibrillation, which delivers more electrical energy to the chest, cardioversion uses less intense electrical shocks to resynchronize heart cells, restoring a regular heart rhythm.

How is electrical cardioversion performed?

Although complications from electrical cardioversion are rare, this procedure requires general anesthesia. It is prepared in advance with the cardiologist. “It takes between 3 weeks and a month of effective anticoagulation and anesthesia counseling before proceeding with electroshock. explained in December 2020 Why Doctor Dominique Dabuty, cardiologist at the University Hospital of Tours. The interesting thing is that during this less anticoagulant preparation, some of the patients very often spontaneously return to sinus rhythm.

The operation, which lasts a maximum of 5 minutes, is performed on an empty stomach on an outpatient basis during a short general anesthetic in the hospital. One or more electric shocks are delivered to restore sinus rhythm. “When the charge is ready, we take the paddles and deliver the electric shock by placing it on the patient’s chest. We need to make sure the paddles keep the headset in their field. By pushing in this way, we provide energy to restore a normal heart rhythm”explains Dr. Xavier Waintraub, cardiologist at La Pitié-Salpêtrière hospital in Paris.

With insufficient anticoagulation, cardioversion may be delayed because of the risk of intracardiac clot formation and stroke.

What are the risks and the success rate?

Electrical cardioversion makes it possible to restore 90% of a normal sinus rhythm, but this success rate can be reduced depending on various risk factors: duration of the arrhythmia, vascular damage, obesity, etc. It does not eliminate the cause or the cause of the arrhythmia. Antiarrhythmic treatment or ablation of atrial fibrillation may be suggested to prevent recurrence.

As for the risks, in addition to general anesthesia, cardioversion can cause a heartbeat that is too slow or some other faster arrhythmia. Inadequate anticoagulation can also lead to a thromboembolic event due to the migration of an intracardiac blood clot.

What are the consequences of the operation?

If there are no complications, the patient can resume normal daily life a few days after the operation. However, he must continue his anticoagulant treatment. Antiarrhythmic treatment can also be adjusted. A cardiologist appointment is made about 1 month after the procedure to check the maintenance of the sinus rhythm. Then two situations can arise, lists Dominique Dabuty. “Either the cardiologist stops lifelong anticoagulation because they have so-called high-risk atrial fibrillation, or we stop because the patient is getting better.”

Below is our Q&A program on the subject of atrial fibrillation:

Leave a Comment