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catheter ablation





catheter ablation
Catheter ablation procedure
Catheter ablation is a medical procedure used to treat some types of arrhythmia. An arrhythmia is a problem with the speed or rhythm of the heartbeat.

During catheter ablation, a long, thin, flexible tube is put into a blood vessel in the patient's arm, groin (upper thigh), or neck. This tube is called an ablation catheter. It's then guided to the heart through the blood vessel. A special machine sends energy through the catheter to the heart. This energy finds and destroys small areas of heart tissue where abnormal heartbeats may cause an arrhythmia to start.


Overview

The heart's electrical system controls the speed and rhythm of the heartbeat. With each heartbeat, an electrical signal spreads from the top of the heart to the bottom. As it travels, the electrical signal causes the heart to contract and pump blood.

The process repeats with each new heartbeat. A problem with any part of this process can cause an arrhythmia.

Catheter ablation is one of several treatments for arrhythmia. A doctor may recommend it if:
  • The medicines a patient is taking don't control his/her arrhythmia.
  • The patient can't tolerate the medicines prescribed for his/her arrhythmia.
  • The patient has a certain type of arrhythmia, such as Wolff-Parkinson-White syndrome.
Though few, catheter ablation has risks. These include bleeding, infection, and pain where the catheter is inserted. More serious problems include blood clots and puncture of the heart.

Cardiologists (doctors who specialize in treating people with heart problems) sometimes perform ablation through open-heart surgery. But this method is not as common as catheter ablation, which doesn't require surgery to open the chest cavity.





Outlook

Catheter ablation alone doesn't always restore a normal heart rate and rhythm. Other treatments may need to be used as well. Also, some people who have the procedure may need to have it done again. This can happen when the first procedure doesn't fully correct the problem.


Who needs catheter ablation?

A doctor may recommend catheter ablation if the patient:
  • Has an arrhythmia that medicine can't control.
  • Can't tolerate the medicines prescribed for his/her arrhythmia.
  • Has certain types of arrhythmia, such as Wolff-Parkinson-White syndrome or some forms of atrial fibrillation.
  • Has abnormal electrical activity in the heart that raises the risk for ventricular fibrillation (a life-threatening arrhythmia) and sudden cardiac arrest.

What to expect before catheter ablation

Before having catheter ablation, a patient should discuss with his/her doctor:
  • How to prepare for the procedure, including limits on eating and drinking. The patient will likely need to stop eating and drinking by midnight before the procedure.
  • Any medicines the patient is taking, and whether he/she should stop taking them before the procedure.
  • Whether he/she has diabetes, kidney disease, or other conditions that may require taking extra steps during or after the procedure to avoid complications.
Some people go home the same day as the procedure. Others need to stay overnight for one or more days. Driving after the procedure may not be safe.


What to expect during catheter ablation

Catheter ablation is done in a hospital. Doctors who do this procedure have special training in cardiac electrophysiology (the electrical system of the heart) and ablation (destruction) of diseased heart tissue.


At the start

Before the procedure, the patient is given medicine through an intravenous (IV) line inserted in a vein in the arm. The medicine helps to the patient relax and may make him/her sleepy. The patient is also connected to several machines that check the heart's activity during the procedure.

Once the patient is drowsy, an area on the patient's arm, groin (upper thigh), or neck is numbed. This is where the ablation catheter (a long, thin, flexible tube) will be inserted into a blood vessel. A needle is used to make a small hole through the skin into the blood vessel. Aa tapered tube called a sheath is put through this hole.

A thin, flexible wire and the catheter is then put through the sheath and into the blood vessel. This guide wire is threaded through the blood vessel to the heart. The wire helps the catheter to be placed correctly.

Special X-ray movies are taken of the guide wire and the catheter as they are moved into the heart. The movies help the doctor see where to place the tip of the catheter.


During the procedure

Electrodes at the end of the catheter are used to stimulate the heart and record its electrical activity. This helps establish where abnormal heartbeats are starting in your heart.

The catheter is moved so that its tip is aimed at the small area of heart tissue where the abnormal heartbeat is starting. A special machine sends energy through the catheter to destroy this very small area of heart tissue.

Types of energy used include radiofrequency (heat generated by electrodes), laser, or cryo- (very cold temperatures).


What the patient may feel

The patient may sleep on and off during the procedure and will generally not feel anything except for:
  • A burning sensation when the doctor injects medicine into the area where the catheter will be inserted
  • Discomfort or burning in the chest when the energy is applied
  • A faster heartbeat during studies of the heart's electrical system
The procedure lasts 3 to 6 hours. When the procedure is done, the ablation catheter will be pulled back and taken out along with the sheath and guide wire. The opening left in the blood vessel is closed and bandaged. Nurses apply pressure to this site to help prevent major bleeding and to help the site begin to heal.


What to expect after catheter ablation

After the procedure, the patient is moved to a special care unit where he/she lies still for 4 to 6 hours of recovery. Lying still prevents bleeding at the site where the catheter was inserted.

While the patient is in the special care unit, he/she is connected to special devices that measure the heart's electrical activity and blood pressure. Nurses check these monitors continuously and also check to make sure that there's no bleeding at the catheter insertion site.


Going home

A doctor determines whether the patient needs to stay overnight in the hospital. Some people go home the same day. Others need to stay overnight for 1 or more days.

Before the patient's, he/she is informed by the doctor:
  • Which medicines to take
  • How much physical activity can be carried out
  • How to care for the area where the catheter was inserted
  • When to see the doctor again
Driving after the procedure may not be safe. The patient will be informed if they needs to arrange for someone to drive them home.


Recovery and recuperation

Recovery from catheter ablation is usually quick. The patient may feel stiff and achy from lying still for 4 to 6 hours after the procedure. In addition, a small bruise may form at the site where the ablation catheter was inserted. The area may feel sore or tender for about a week. Most people are able to return to normal activity in a few days.

The doctor will give information about signs and symptoms to watch for. The patient should tell the doctor if he/she has problems such as:
  • A constant or large amount of bleeding at the catheter insertion site that can't be stopped with a small bandage
  • Unusual pain, swelling, redness, or other signs of infection at or near the catheter insertion site
  • Strong, rapid, or other irregular heartbeats
  • Fainting

What are the risks of catheter ablation?

Though few, catheter ablation does have risks. Possible problems are:
  • Bleeding, infection, and pain where the catheter was inserted.
  • Damage to blood vessels. This complication is very rare. It's caused by the catheter scraping or poking a hole in a blood vessel as it's guided to the heart.
  • Puncture of the heart.
  • Damage to the heart's electrical system. This may lead to the need for a permanent pacemaker. A pacemaker is a small device that's placed under the skin of your chest or abdomen to help control abnormal heart rhythms.
  • Blood clots, which could lead to stroke or other damage.
  • Narrowing of the veins that carry blood from the lungs to the heart. This is called stenosis.
As with any heart procedure, complications can sometimes, although rarely, be fatal. The risk of complications is higher if the patient has diabetes or kidney disease. It also is higher if the patient is 75 years old or older.


Related category

   • HEALTH AND DISEASE