Catheter Ablation for Atrial Fibrillation
If medicine is not effective or not tolerated foratrial fibrillation, a nonsurgical procedure called catheter ablation may be chosen. Catheter ablation for atrial fibrillation is relatively new and is still being studied.
In this procedure thin, flexible wires are inserted into a vein in the groin and threaded up through the vein and into the heart. There is an electrode at the tip of the wires. The electrode sends out radio waves that create heat. This heat destroys the heart tissue that causes atrial fibrillation or the heart tissue that keeps it happening. Another option is to use freezing cold to destroy the heart tissue.
Atrial Fibrillation and Heart Disease
The heart has four areas, or chambers. During each heartbeat, the two uppers chambers (atria) contract, followed by the two lower chambers (ventricles). This action is directed by the heart's electrical system. The electrical impulse begins in an area called the sinus node, located in the upper part of the right atrium. When the sinus node fires, an impulse of electrical activity spreads through the right and left atria, causing them to contract, forcing blood into the ventricles. Then the electrical...
Ablation procedures either try to cure atrial fibrillation (focal ablation, circumferential ablation, and pulmonary vein ablation) or try to control your symptoms (nodal ablation).
- Heart Problems: Should I Have Catheter Ablation?
Ablation to cure atrial fibrillation
Focal and circumferential catheter ablation are used to try to cure atrial fibrillation. Focal ablation, also known as targeted ablation, is used to destroy the specific areas in the heart that are firing off abnormal electrical impulses and causing atrial fibrillation. Circumferential ablation is used to destroy the tissue that lets atrial fibrillation continue. Sometimes, a doctor uses both focal and circumferential ablation.
Pulmonary vein ablation is also used to try to cure atrial fibrillation. Sometimes, abnormal impulses come from inside a pulmonary vein and cause atrial fibrillation. (The pulmonary veins bring blood back from the lungs to the heart.) Catheter ablation in a pulmonary vein can block these impulses and keep atrial fibrillation from happening.
A pacemaker is usually not needed when catheter ablation is done on the pulmonary vein or other targeted tissue.
View aslideshow of pulmonary vein or focal ablation
to see how the heart's electrical system works, how atrial fibrillation happens, and how pulmonary vein or focal ablation is performed.
In some cases, catheter ablation may be done by applying radiofrequency energy to the outside or inside surface of the heart during open-heart surgery. This may be an option if you are already having heart surgery for another reason, such ascoronary artery bypassor valve replacement surgery.
Ablation to control symptoms of atrial fibrillation
Nodal catheter ablation, also known as AV node ablation, can control symptoms of atrial fibrillation when the cause cannot be stopped. You may need AV node ablation if targeted or pulmonary vein ablation did not stop your atrial fibrillation, or if these procedures will not help you. With AV node ablation, the entireatrioventricular (AV) nodeis destroyed. After the AV node is destroyed, it can no longer send impulses to the lower chambers of the heart (ventricles). This controls atrial fibrillation symptoms.
After AV node ablation, a permanentpacemakeris needed to regulate your heart rhythm. Nodal ablation can control your heart rate and reduce your symptoms, but it does not prevent or cure atrial fibrillation. So you will probably need to takeanticoagulation therapysuch as warfarin.
View aslideshow of AV node ablationto see how the heart's electrical system works, how atrial fibrillation happens, and how AV node ablation is performed.
You will be given medicine to help you relax. Alocal anestheticwill numb the site where the catheter is inserted. The procedure is done in a hospital where you can be watched carefully.
What To Expect After Treatment
Recovery from catheter ablation is usually quick. You may be hospitalized for 1 to 2 days so that your doctor can monitor your heart rate.
Many people think that having ablation means they'll be able to stop taking an anticoagulant (also called a blood thinner), such as warfarin, every day to prevent stroke. But that is only true if your risk of stroke is low. Studies haven't shown that ablation for atrial fibrillation lowers your risk of stroke. So you'll still need to take an anticoagulant if your risk of stroke remains high. Your doctor can tell you about your stroke risk. See the:
After an ablation, you might take an antiarrhythmic medicine to help keep your heart in a normal rhythm.
You might feel a flutter in your heart after the ablation procedure. The flutter usually goes away after your heart heals. If your flutter does not go away, you may need a second ablation procedure.
Why It Is Done
Ablation might be done if you have symptoms of atrial fibrillation that won't go away, if your medicine hasn't brought back a normal heartbeat, or if your medicine causes side effects that are hard to live with.
This treatment does have some serious risks, but they are rare. Many people decide to have ablation because they hope to feel much better afterward, and that hope is worth the risks to them. But the risks may not be worth it for people who have few symptoms or for those who are less likely to be helped by ablation.
How Well It Works
Catheter ablation is more successful in people who have atrial fibrillation that comes and goes (paroxysmal) than in people who have atrial fibrillation that is persistent or chronic (constant).
- Research shows that ablation helps 80 out of 100 people who haveatrial fibrillation that comes and goes(paroxysmal). That means it does not help in 20 out of 100 cases.1
- Ablation works for about 60 out of 100 people who havepersistent or chronic (constant) atrial fibrillation.That means it doesn't work in 40 out of 100 cases.1
If the first procedure does not get rid of atrial fibrillation completely, catheter ablation may need to be done a second time. Repeated catheter ablations have a higher chance of being successful.
Catheter ablation is still being studied to see how well it works and how safe it is in the long term.
Risks
Catheter ablation is thought to be safe. It has some serious risks, but they are rare. They include:
- Stroke.
- Heart attack.
- Puncture of the heart.
- Need for emergency heart surgery.
- Problems with the pulmonary vein.
- A leaking blood vessel.
- Nerve damage that causes paralysis of thediaphragm.
- Pericarditis.
- Cardiac tamponade.
- Atrio-esophageal fistula. In this life-threatening condition, a hole forms between the heart's upper chamber and the esophagus.
- Bleeding.
- New heart rhythm problems.
- Death (very rare).
You will have to decide whether the possible benefits of ablation outweigh these risks. Your doctor can help you decide.
What To Think About
Certain people shouldn't have ablation
Ablation isn't a choice for some people, including those who:
- Aren't able to lie still or cooperate with the doctor doing the test.
- Have a history of bleeding problems.
- Have a blood clot in theleft atrium of the heart
.
Complete the special treatment information form (PDF) to help you understand this treatment.
Citations
Callahan TD IV, Natale A (2008). Catheter ablation of atrial fibrillation.Medical Clinics of North America, 92(1): 179–201.
| By | Healthwise Staff |
| Primary Medical Reviewer | E. Gregory Thompson, MD - Internal Medicine |
| Specialist Medical Reviewer | John M. Miller, MD - Electrophysiology |
| Last Revised | February 15, 2011 |
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