What is catheter ablation?
Catheter ablation is a procedure in which a thin, flexible tube or catheter is inserted into a blood vessel in your arm, neck or groin. These catheters are then threaded through the blood vessel to the heart. The doctor can then apply radiofrequency energy, laser energy or freezing temperature (cryoablation) to destroy the abnormal heart tissue which causes the arrythmia or irregular heart beat.
Catheter ablation is considered a minimally invasive procedure since there are no incisions made to the chest wall to access the heart. Therefore, it is a relatively simple and routine procedure that carries a low risk to patients.
There are two types of catheter ablation that are performed:
Radiofrequency catheter ablation
Radiofrequency catheter ablation directs radiofrequency energy through a catheter to the areas of your heart tissue that cause erratic electrical signals. Scarring the tissue will correct the arrhythmia. In other cases, catheters that freeze the heart tissue, known as cryotherapy, can be used to get the same result. In radio frequency catheter ablation, your physician will use short bursts of intense energy to scar dysfunctional tissue which will stop it from sending disruptive electrical signals.
Cryoblation (Cryoballoon ablation)
Cryoballoon ablation is a balloon-based technology that blocks the conduction of the arrhythmia in cardiac tissue through the use of a coolant rather than heat, by way of a catheter. This freezing technology allows the catheter to adhere to the tissue during ablation, allowing for greater catheter stability. Cryoablation is a new and alternative method that uses freezing temperatures on targeted areas around the pulmonary veins. This method is favored by many physicians because it can be performed temporarily and tested for effectiveness before the arrhythmia site is scarred permanently.
Why it's done
Catheter ablation is performed when:
- Medicine doesnâ€™t control your irregular heartbeat, or you canâ€™t tolerate the medicine needed to control the arrythmia
- You are diagnosed with atrial fibrillation or Wolffâ€“Parkinsonâ€“White syndrome
- You have abnormal electrical activity that puts you at risk for life-threatening arrhythmias, such as ventricular fibrillation and sudden cardiac death
During catheter ablation, your physician will control the movement of the catheter externally. With the help of computer software, the areas which are affected are identified. Depending on which procedure is to be performed, the catheter will be fitted with electrodes or a cryoballoon system.
Some of the risks of cardiac ablation include:
- Bleeding at the catheter insertion site
- Damage to blood vessels or perforations
- Damage to the heartâ€™s electrical signals from over-ablation
- Pain at catheter insertion site
- Postoperative blood clotting
- Allergy to contrast dye used
This procedure carries varying degrees of success. Ablation alone doesnâ€™t always restore normal rate and rhythm. Other treatments may need to be used in addition and sometimes the ablation may even need to be repeated.
What to expect
Catheter ablations are performed in the hospital under the direction of an electrophysiology doctor and staff. In some instances, when an ablation is done during open heart surgery, a cardiothoracic surgeon will perform the procedure.
When you arrive at The Heart Institute, you will be greeted by our nursing staff who will get you prepared for the procedure and provide you with a hospital gown. You will then meet with your doctor to discuss last minute questions you may have.
Catheter ablation is generally performed under sedation with local anesthetic, without putting you to sleep. The anesthesiologist will be onsite throughout the procedure to ensure you are comfortable. General anesthetic will be used in certain circumstances, particularly if the patient is a child. You can expect the procedure to take anywhere from three to six hours.
You will notice a fluoroscopy machine above you that X-rays your chest so that your physician can monitor the position of the catheter. Your physician will also see detailed ultrasound images transmitted from sensors in the catheter. He will then use one of the energy forms to destroy the area where the abnormal beats are starting.
Afterward, you will be expected to lie still for four to six hours in a recovery room. Some patients go home that same day where others may be required to stay overnight or a few days. During this time, you may feel tired or dazed as you recover from the sedative. You may have some pressure bandages covering the catheter incision site.
You may need to make arrangements for transportation the day of the procedure since your doctor may advise against driving.
Recovery from catheter ablation is quick, although you may feel some soreness at the site of the catheter. Your doctor will give you instructions, if needed. Most people will return to their normal activity within a few days.