Normally, your heart has a strong, steady beat. That beat is controlled by the heart's electrical system. Sometimes that system misfires, causing a heartbeat that is too fast and isn't steady.

Cardiac ablation is a way to get into your heart—without surgery—and fix the misfiring. It's like working on the spark plugs in your car without having to open the hood.

• It's done in a hospital.
• The doctor inserts thin, flexible wires—catheters—into a blood vessel in your neck or leg and threads them up into your heart.
• X-rays help the doctor see where to move the catheters.
• The catheters use very hot or very cold temperatures to destroy the areas in your heart that are causing the misfiring problem.

It may seem like a bad idea to destroy parts of your heart on purpose. But the areas that are destroyed are very tiny and don't affect your heart's ability to do its job.

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 the left atrium of the heart .

Ablation might be done if you have symptoms 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 people who are less likely to be helped by ablation.

Heart rhythm problems that may be treated with ablation include:

• Atrial fibrillation.
• Supraventricular tachycardia (SVT).
• Heart flutter, or atrial flutter.
• Ventricular tachycardia.

Taking anticoagulants (blood thinners)

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.

Catheter ablation works quite well for fast heart rates known as supraventricular tachycardia, or SVT. It doesn't work as well for atrial fibrillation.

• Ablation for SVT: Catheter ablation helps most people with this type of rhythm problem.
• Ablation for atrial fibrillation:
  • Research shows that ablation helps 80 out of every 100 people who have atrial 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 have persistent or chronic (constant) atrial fibrillation. That means it doesn't work in 40 out of 100 cases.¹
  • When ablation does work, experts don't know how long it lasts. More research is needed before we can say how long ablation keeps most people out of atrial fibrillation.

If the first ablation does not get rid of a heart rhythm problem completely, you may need to have it done a second time. Repeated ablations have a higher chance of success.

Most people who have catheter ablation don't need a pacemaker. Although ablation destroys tiny areas of tissue in the heart, it doesn't usually keep your heart from doing its job.

But some people do need a pacemaker:

• If you have the fast heart rate known as atrial fibrillation and regular ablation doesn't help, you may need a special type of ablation called AV node ablation . With AV node ablation, the entire atrioventricular (AV) node is destroyed. Then you need a permanent pacemaker to take over the AV node's job of coordinating your heart rate.
• About 1 out of 100 people who have the fast heart rate known as AVNRT needs a permanent pacemaker after ablation. This means that 99 out of 100 people with AVNRT will not need a pacemaker.²

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 the diaphragm.
• 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.