What is Catheter Ablation and Why is it Done?

The heart's electrical system doesn't always work right. This can cause abnormal heart rhythms which are called arhythmias. During this time, the heart may beat too fast, too slowly, or irregularly. Catheter ablation is used then to destroy parts of an abnormal electrical pathway that is causing rapid heart beat, called tachycardia.

Tachycardias happen when the heart beats too fast. Some of the symptoms might be palpitations, dizziness, fainting spells, chest pain, and shortness of breath. Sometimes this can be life-threatening. Others may simply go unnoticed.

Most cases are caused by an abnormal pathway, called a re-entry circut. If electrical impulses enter this pathway, it may start traveling in a circle. This can make the heart contract each time the impulse travels through the pathway. The end result is a very rapid heart beat.

The following are a few examples of tachycardias that may be treated with catheter ablation:

AV Nodal Re-entrant - A re-entry circuit exists in or next to the AV node and may cause attacks of tachycardia. This attack can last from less than a minute to as long as a few hours. This often happens in young or middle aged adults who don't have heart disease.

Tachycardia Caused by an Accessory Pathway - This condition, sometimes called WPW Syndrome, is an abnormal "bridge" of tissue, called an accessory pathway, which connects the atria and ventricles. This extra pathway may cause extremely rapid heart beat and in some cases can be life-threatening.

Focal Atrial Tachycardia - An abnormal site or focus, in one of the atria fires electrical impulses rapidly. Focal atrial tachycardia often occurs in people with heart or lung disease.

Atrial Fibrillation - This is multiple waves of electrical activity flow across the atria, which causes them to quiver or fibrillate. The heart rhythm is irregular, erratic, and usually very fast. Atrial fibrillation may occur once in a while, or all the time. Sometimes it can cause stroke.

Atrial Flutter - The re-entry circuit in the right atrium causes attacks of tachycardia. As in atrial fibrillation, the atria beat is very fast. But unlike fibrillation, the fast heart beat remains regular.

Ventricular Tachycardia - This is one or more re-entry circuits that exist in the ventricles and usually in an area of the heart muscle that has been damaged by heart attack or disease. Can cause very rapid heart beat. Because the ventricles do most of the pumping, tachycardias that start in the ventricles are more dangerous. An attack of ventricular tachycardia may lead to cardiac arrest.

Catheter ablation is used to destroy parts of an abnormal electrical pathway that's causing the rapid heart beat. It is a fairly lo risk procedure than can take the place of surgery in a lot of cases. And it may also permanently cure the tachycardia.

Catheter ablation is an excellent treatment option for people who have had symptoms from tachycardia, especially if their medications don't help the problem. It is also an option for people who can't take, or wish not to take medications because of the side effects or they interfere with their quality of life.

During the catheter ablation a doctor will guide an ablating electrode catheter into the heart, generally via the femoral artery through the groin. They place the catheter so that it lies close to the abnormal electrical pathway that is causing the arhythmia. Then they will pass radio frequency energy through the catheter.

The tip of the catheter will then heat up and destroy the small area of the heart tissue that contains the abnormal pathway. The rest of the heart muscle will be unharmed. This will cause scar tissue to form resulting in the inability to transmit electrical impulses and can no longer cause arthythmias.

If you have any of these types of arthythmias you might want to talk to your doctor about catheter ablation.