How Catheter Ablation Regulates Your Heartbeat

Many cases of arrhythmia can be traced to a single spot transmitting rogue electrical signals in the heart. Catheter ablation uses high-frequency radio waves to defuse those troublemaking spots. The treatment is especially effective for treating atrial fibrillation and tachycardias.

For six months after quadruple bypass surgery, Alfred Pasquale, 67, of San Rafael, Calif., experienced a fluttering of the heart that made him feel shaky and his recovery uncomfortable. "After I had the ablation, I no longer had this irregular heartbeat and I now feel much better."

Young, healthy patients with atrial fibrillation can expect a success rate of 90% with catheter ablation, says Adrian Hernandez, MD, a cardiologist with the Duke Clinical Research Institute. Older people or those with serious illnesses can expect a success rate of 40% to 70%.

Catheter ablation is a procedure used to selectively destroy areas of the heart that are causing a heart rhythm problem. During this procedure, thin, flexible wires are inserted into a blood vessel in the thigh, groin, neck, or elbow and threaded up through the blood vessel and into the heart under X-ray guidance. The wires allow the doctor to record the electrical activity of your heart and determine what kind of heart rhythm problem you have. Through these wires, electrical energy (radio waves) can be sent to a specific area of your heart. This will destroy (ablate) the tiny part of your heart that is causing its rhythm problem.

Catheter ablation that uses radio waves is called radiofrequency catheter ablation. These radio waves can be delivered to your heart muscle at the site of the “short circuit.” The radio waves (radiofrequency energy) cause a tiny area of heart muscle to be heated and selectively destroyed (ablated), thereby curing your heart rhythm problem. New energy sources for catheter ablation such as liquid nitrogen (cryoablation) are being used. But there is no evidence that these new energy sources are better than the standard radiofrequency catheter ablation.

Catheter ablation is done in a hospital where the person can be carefully monitored. The procedure is done after an electrophysiology (EP) study, which can identify specific areas of heart tissue where the fast heart rate may start or where abnormal electrical pathways are located inside or outside the atrioventricular (AV) node. This allows doctors to pinpoint exactly what tiny area of heart muscle to destroy.

A local anesthetic is used at the site where the catheter is inserted. The person usually stays awake during the procedure but may be sedated.

What to expect after treatment
Recovery from catheter ablation is usually quick. Some people may be hospitalized for 1 to 2 days after the procedure so doctors can monitor heart rate and rhythm. Many people go home the same day.

Why catheter ablation is done
Catheter ablation is often used for people with persistent or recurrent fast heart rates that do not respond to drug therapy, or people with certain types of fast heart rates who do not want to take medicine.

How well it works
In the case of atrioventricular nodal reciprocating tachycardia (AVNRT), a type of supraventricular tachycardia, a recent study showed that catheter ablation eliminated AVNRT in 96% of cases.

Catheter ablation is often recommended for people with a type of atrioventricular reciprocating tachycardia (AVRT) called Wolff-Parkinson-White (WPW) syndrome, especially those who have severe symptoms or also have atrial fibrillation or flutter. This procedure can successfully eliminate WPW most of the time. There is a small risk of the arrhythmia recurring even after successful ablation of WPW. However, a second session of catheter ablation is usually successful.

Risks
The risks of catheter ablation include:
  • Bruising
  • Bleeding
  • Damage to the conduction system of the heart, requiring placement of a pacemaker (rare)
  • Puncture of the heart, resulting in cardiac tamponade (rare)
  • Pericarditis, inflammation of the sac (pericardium) that surrounds and protects the heart (rare)
  • Pulmonary embolism (rare)
In catheter ablation for atrioventricular nodal reentrant tachycardia (AVNRT), damage to the heart's conduction system requires a permanent pacemaker in about 1% of people. With other types of supraventricular tachycardia, where the abnormal cells are not close to the heart's normal conduction system, there is almost no risk of needing a pacemaker.

Last Updated: September 26, 2006 See Full Credits Disclaimer

Lead writer: Chris Woolston
Last Updated: May 13, 2008
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