Cardiac ablation is a procedure to scar or destroy tissue in your heart that's allowing incorrect electrical signals to cause an abnormal heart rhythm. Diagnostic catheters are threaded through blood vessels to your heart where they are used to map your heart's electrical signals. Ablation catheters transmit heat or cold to scar or destroy tissue. This illustration shows ablation catheters being applied near the pulmonary veins in a type of cardiac ablation called pulmonary vein isolation.
Atrial fibrillation ablation is a procedure used to treat an irregular heart rhythm (arrhythmia) that starts in the heart's upper chambers (atria). It's a type of cardiac ablation, which works by scarring or destroying tissue in your heart to disrupt faulty electrical signals causing the arrhythmia.
Atrial fibrillation ablation may be used if medications or other interventions to control an irregular heart rhythm don't work. Rarely, it's the first choice of treatment for atrial fibrillation.
Treatment for atrial fibrillation usually improves your symptoms, such as fatigue and shortness of breath. Without treatment, atrial fibrillation tends to get worse over time.
Types of atrial fibrillation ablation
The type of atrial fibrillation ablation procedure you have depends on what's causing your irregular heart rhythm and whether you have other heart conditions. Three types of atrial fibrillation ablation are:
- Catheter ablation. The doctor threads long, thin tubes (catheters) into the heart and applies heat or extreme cold. This causes tiny scars in certain parts of the heart muscle, which disrupt or eliminate the erratic electrical signals in your heart. You may also hear the procedure called pulmonary vein isolation, which is a type of catheter ablation.
Maze procedure. Maze is an ablation technique done during open-heart surgery. Your doctor creates a pattern (maze) of scar tissue in the upper chambers of your heart, using a scalpel or an ablation device. As with catheter ablation, the scarring disrupts the stray electrical signals that cause some types of arrhythmia.
The maze procedure may be right for you if your atrial fibrillation doesn't respond to other treatments or if you're also undergoing other necessary heart surgery, such as coronary artery bypass surgery or heart valve repair.
AV node ablation. With atrioventricular (AV) node ablation, your doctor uses catheters to create scarring in an area of your heart called the AV node. This is the point connecting the upper chambers (atria) and lower chambers (ventricles). The scar tissue prevents the atria from sending faulty electrical impulses to the ventricles.
AV node ablation may be a good option for you if your atrial fibrillation doesn't get better with other treatments. You may also need a pacemaker to regulate your heart rhythm after an AV node ablation.
How it works
Each beat of your heart is triggered by an electrical impulse normally generated from special cells in the upper right chamber of your heart (pacemaker cells). These signals are faulty in people who have atrial fibrillation, firing so rapidly that the upper chambers of your heart quiver (fibrillate) instead of beating efficiently. These rapidly discharging triggers are called hot spots. To restore a normal heart rhythm, the sources of these hot spots must be isolated from the rest of the heart.
The most common technique for treating atrial fibrillation is catheter ablation. In this procedure, your doctor threads one or more long, thin tubes (catheters) through blood vessels to your heart. He or she uses a mapping catheter to determine where the triggers are located and then applies extreme cold or heat with the catheter tips to destroy (ablate) these spots. This causes scarring that disrupts the faulty electrical signals and restores normal heart rhythms.
The use of extreme cold to cause scarring (cryoablation) is a newer technique. The doctor runs a catheter from the groin to the area of the heart where the arrhythmia originates. He or she then uses it to deploy and inflate a tiny balloon that freezes the area. The result is scar tissue that stops the firing pathway of the faulty signals. This technique takes less time than heat ablation and may have similar risks and complications.
Mayo Clinic's approach
Why it's done
Atrial fibrillation ablation is used to reduce signs and symptoms and improve quality of life. It may be an option for people whose heart quiver (fibrillation) can't be corrected with medication or other treatments. Your doctor might even suggest this procedure before trying medications if, for example, you want to correct the problem without the risk of medication side effects.
About atrial fibrillation
In a normal heart rhythm, a tiny cluster of cells at the sinus node sends out an electrical signal. The signal then travels through the atria to the atrioventricular node and then passes into the ventricles, causing them to contract and pump out blood.
In a normal heart rhythm, a tiny cluster of cells at the sinus node sends out an electrical signal. The signal then travels through the atria to the atrioventricular (AV) node and then passes into the ventricles, causing them to contract and pump out blood. In atrial fibrillation, electrical signals fire from multiple locations in the atria (typically pulmonary veins), causing them to beat chaotically. The AV node — your heart's natural pacemaker — is unable to prevent all of these chaotic signals from entering the ventricles. Your ventricles respond to these extra, chaotic signals by beating faster than normal.
Atrial flutter is a type of heart rhythm disorder in which the heart's upper chambers (atria) beat too quickly.
During atrial fibrillation the heart's two upper chambers (atria) beat chaotically and irregularly — out of coordination with the two lower chambers (ventricles). People with this heart condition may feel pounding in the chest (palpitations), shortness of breath and weakness. This condition can also put them at increased risk of a stroke. The condition often gets worse over time if left untreated.
The risks of atrial fibrillation ablation vary depending on whether you are undergoing a catheter ablation or open-heart surgery, which is less common. Risks include:
- Bleeding or infection at the surgical site or where your catheter was inserted
- Damage to your blood vessels
- Puncture of your heart
- Damage to your heart valves
- Damage to your heart's electrical system, which could worsen your arrhythmia and require a pacemaker to correct
- Blood clots in the legs or lungs (venous thromboembolism)
- Stroke or heart attack
- Narrowing of the veins that carry blood between your lungs and heart (pulmonary vein stenosis)
- Death in rare cases
Discuss the risks and benefits of atrial fibrillation ablation with your doctor to understand if it's right for you.
How you prepare
Your doctor will examine you and order several tests to evaluate your heart condition. He or she will discuss with you the risks and benefits of your atrial fibrillation ablation procedure. Let your doctor know about allergies or reactions you've had to medications. And tell him or her if you're pregnant or planning to become pregnant.
You'll need to stop eating and drinking the night before your procedure. If you take any medications, ask your doctor if you should continue taking them before your procedure. In some cases, you'll be instructed to stop taking medications to treat a heart arrhythmia several days before your procedure.
If you have an implanted heart device, such as a pacemaker or implantable cardioverter-defibrillator, talk to your doctor to see if you need to take any special precautions.
What you can expect
The most common method of atrial fibrillation ablation is catheter ablation. Other types are AV node ablation and the maze procedure, which is done during open-heart surgery.
During catheter ablation for atrial fibrillation
Catheter insertion points for cardiac ablation
During cardiac ablation, catheters are passed through a vein in order to reach your heart. Catheters may be inserted in your groin, your shoulder or your neck.
Catheter ablation for atrial fibrillation is performed in a hospital. Before your procedure, a specialist will insert an intravenous line into your forearm or hand, and you'll be given a sedative to help you relax. In some situations, a general anesthetica may be used instead to place you in a sleep-like state.
After your sedative takes effect, your doctor or another specialist will numb a small area near a vein on your groin, neck or shoulder. Your doctor will insert a needle into the vein and place a tube (sheath) through the needle.
Your doctor will thread catheters through the sheath and guide them to several places within your heart. Your doctor may inject dye into the catheter, which helps him or her see your blood vessels and heart using X-ray imaging. The catheters have electrodes at the tips that can be used to send electrical impulses to your heart and record your heart's electrical activity. This process of using imaging and other tests to determine what's causing your arrhythmia is called an electrophysiology (EP) study.
Next your doctor uses the catheter tips to apply heat (radiofrequency ablation) or cold (cryoablation) to the target area to destroy tissue and cause scarring.
The procedure usually takes three to six hours. Complicated procedures may take longer.
During the procedure it's possible you'll feel some minor discomfort when the dye is injected in your catheter or when energy is run through the catheter tips. If you experience any type of severe pain or shortness of breath, let your doctor know.
After catheter ablation for atrial fibrillation
Following your procedure, you'll be moved to a recovery area to rest quietly for four to six hours to prevent bleeding at your catheter site. Your heartbeat and blood pressure will be monitored continuously to check for complications.
Depending on your condition, you may be able to go home the same day as your procedure. If you go home the same day, plan to have someone drive you.
You may feel a little sore after your procedure, but the soreness shouldn't last more than a week. You'll usually be able to return to your normal activities within a few days after undergoing cardiac catheter ablation.
Atrial fibrillation ablation may reduce the signs and symptoms of your heart rhythm problem and improve your quality of life. But it hasn't been shown to reduce your risk of a stroke, so your doctor may recommend that you continue blood-thinning medications.
Your irregular heart rhythm may recur, sometimes as long as three years later. Recurrence is more likely in older people and in those with other heart conditions, high blood pressure or a history of difficult-to-treat atrial fibrillation.
You'll likely have a follow-up appointment with your doctor about three months after surgery. If your atrial fibrillation does come back, you may now be able to control it with medications. Some people need another ablation procedure. The Heart Rhythm Society and American College of Cardiology recommend that you heal for at least three months before having a repeat procedure.
Even after successful ablation, your doctor may suggest that you use a continuous heart rhythm monitoring device, such as an implantable loop recorder. If you continue to have heart rhythm problems, your doctor may recommend a permanent pacemaker.
Explore Mayo Clinic studies testing new treatments, interventions and tests as a means to prevent, detect, treat or manage this disease.
Nov. 13, 2019