Cardioversion is a medical procedure used to restore a normal heart rhythm in people with certain types of abnormal heartbeats, known as arrhythmias. It is commonly used to treat conditions like atrial fibrillation (AFib), atrial flutter, or other rapid, irregular heartbeats. There are two primary types of cardioversion: electrical and pharmacological (medication-based), with electrical cardioversion being the more commonly recognized procedure.
Understanding Arrhythmias and Cardioversion
The heart normally beats in a consistent rhythm, coordinated by electrical signals generated in the heart’s natural pacemaker. Arrhythmias occur when these signals are disrupted, causing the heart to beat too fast, too slow, or irregularly. This can lead to symptoms such as dizziness, shortness of breath, chest pain, and in severe cases, increased risk of stroke or heart failure.
Cardioversion aims to correct these abnormal rhythms and restore the heart’s natural beat, often improving a patient’s quality of life and reducing the risk of complications.
Types of Cardioversion
- Electrical Cardioversion: This is the most common form of cardioversion, where controlled electrical shocks are delivered to the heart through patches or paddles placed on the chest. The procedure is typically done in a hospital under sedation to prevent discomfort. The electrical shock momentarily stops the heart’s abnormal rhythm, allowing its natural pacemaker to resume control, ideally restoring a normal rhythm.
- Procedure: Before cardioversion, patients usually undergo tests like an electrocardiogram (ECG) or echocardiogram to ensure there are no underlying complications, such as blood clots, which can be dislodged during the procedure. The procedure is brief, and patients are monitored afterward to ensure their heart maintains a regular rhythm.
- Pharmacological Cardioversion: In this method, medications (called antiarrhythmics) are used to correct the heart’s rhythm. These drugs can be administered intravenously or orally. While it can be less invasive than electrical cardioversion, pharmacological cardioversion often takes longer to take effect and may not be as immediately successful in restoring a normal heart rhythm.
When is Cardioversion Used?
Cardioversion is typically recommended for patients experiencing symptomatic arrhythmias, particularly atrial fibrillation, and atrial flutter, which do not resolve on their own. It is generally considered when:
- Medications to control heart rate or rhythm have not been effective.
- The arrhythmia causes significant symptoms, such as fatigue, palpitations, or shortness of breath.
- There is a risk of blood clot formation, especially in AFib patients.
However, cardioversion is not suitable for everyone. For instance, it may not be recommended for patients with long-standing atrial fibrillation or those with structural heart problems that make restoring a normal rhythm difficult.
Risks and Considerations
Although cardioversion is generally safe, it does come with some risks:
- Blood clots: There is a risk that cardioversion can dislodge a blood clot in the heart, leading to stroke. To mitigate this, patients are often prescribed blood thinners before and after the procedure.
- Arrhythmias: In rare cases, the procedure may cause more severe arrhythmias, requiring further intervention.
- Skin irritation: Electrical cardioversion can cause mild burns or irritation where the paddles or patches are placed.
- Failure to convert: Cardioversion may not always be successful, and the abnormal rhythm could return, requiring additional treatment or procedures.
Post-Cardioversion Care
After cardioversion, patients are usually monitored to ensure that their heart rhythm remains stable. Depending on the underlying cause of the arrhythmia, long-term medication may be needed to prevent a recurrence. Blood thinners may also be continued for several weeks or months to reduce the risk of stroke.
« Back to Glossary Index