Cardioversion is a medical procedure used to restore a normal heart rhythm when the heart is beating abnormally fast or irregularly, most commonly in conditions such as atrial fibrillation or atrial flutter. The purpose of cardioversion is to reset the heart’s electrical activity and allow the normal rhythm to resume.
Cardioversion does not treat the underlying cause of the rhythm disorder, but it can be highly effective in terminating an ongoing arrhythmia and relieving symptoms such as palpitations, shortness of breath, fatigue, or dizziness.
Why Cardioversion Is Performed
In some heart rhythm disorders, the heart remains stuck in an abnormal rhythm instead of returning to normal on its own. When this happens, cardioversion may be recommended to interrupt the abnormal electrical pattern and restore coordinated heartbeats.
Cardioversion is most often used in atrial fibrillation and atrial flutter, but it may also be applied in other selected supraventricular arrhythmias when rhythm control is desired.
The decision to perform cardioversion depends on symptom severity, arrhythmia duration, underlying heart disease, and overall treatment goals.
Types of Cardioversion
There are two main ways cardioversion can be performed, both aiming to achieve the same result.
- Electrical cardioversion uses a controlled electrical shock delivered to the chest to reset the heart rhythm.
- Pharmacological (chemical) cardioversion uses medications to restore normal rhythm without an electrical shock.
The choice between these approaches is individualized and based on clinical context.
Electrical Cardioversion: What to Expect
Electrical cardioversion is a planned, short procedure performed in a hospital setting. Patients are given brief anesthesia or deep sedation so they are asleep and feel no pain.
Special pads or paddles are placed on the chest, and a carefully timed electrical shock is delivered to the heart. The shock lasts only a fraction of a second and is synchronized with the heart’s rhythm to ensure safety.
In many cases, normal rhythm is restored immediately. Patients typically wake up within minutes and are monitored for a short period afterward.
Medication-Based Cardioversion
In some patients, medications may be used to restore normal rhythm. These drugs act on the heart’s electrical system and can sometimes convert atrial fibrillation or flutter back to normal rhythm over hours or days.
Medication-based cardioversion may be chosen when electrical cardioversion is not urgent, when anesthesia is not desirable, or as part of a longer-term rhythm control strategy.
Anticoagulation and Stroke Prevention
One of the most important aspects of cardioversion is stroke risk management. When the heart is in atrial fibrillation, blood clots can form in the atria. Restoring normal rhythm can dislodge these clots if proper precautions are not taken.
For this reason, blood-thinning medication is often required before and after cardioversion, depending on how long the arrhythmia has been present and the patient’s individual stroke risk. In some cases, imaging of the heart is performed before cardioversion to ensure no clot is present.
Recovery After Cardioversion
Recovery from cardioversion is usually quick. Most patients go home the same day and resume normal activities within 24 hours.
Mild skin irritation where the pads were placed or temporary fatigue may occur. These effects are usually short-lived.
How Effective Is Cardioversion?
Cardioversion is often very effective at restoring normal rhythm in the short term. However, it does not prevent the arrhythmia from returning. Many patients experience recurrence unless additional treatment—such as medications or catheter ablation—is used to maintain normal rhythm.
Because of this, cardioversion is often part of a broader treatment plan rather than a standalone solution.
When Cardioversion May Not Be Appropriate
Cardioversion is not always the best option. In patients with long-standing atrial fibrillation, minimal symptoms, or high likelihood of immediate recurrence, other strategies such as rate control may be preferred.
The decision is individualized and based on a careful balance of benefits and risks.
In Summary
Cardioversion is a safe and effective procedure used to restore normal heart rhythm in selected patients with atrial fibrillation, atrial flutter, and other arrhythmias. It can rapidly relieve symptoms and improve quality of life, but it does not address the underlying cause of the rhythm disorder. For many patients, cardioversion is an important step within a comprehensive rhythm management strategy that may also include medications or catheter ablation.
Reference: Cardioversion
