Catheter Ablation for the Treatment of Atrial Fibrillation

About This Procedure

Physicians at the Massachusetts General Hospital Corrigan Minehan Heart Center use a minimally invasive technique called catheter ablation to treat atrial fibrillation. The goal of this procedure is to ablate the electrical connections between the pulmonary veins and the atrium. The pulmonary veins are blood vessels that drain blood from the lungs into the heart, and the atria includes the two smaller chambers of the heart. The procedure is also known as pulmonary vein isolation.

Research has shown that abnormal tissues within and around the pulmonary veins can trigger and sustain atrial fibrillation. These abnormal tissues fire rapid electrical activity and put the heart into atrial fibrillation. By electrically isolating the pulmonary veins from the atria, abnormal electrical activity within the veins cannot trigger atrial fibrillation.

Learn more about the Telemachus & Irene Demoulas Family Foundation Center for Cardiac Arrhythmias >

What Happens During Catheter Ablation?

During catheter ablation, physicians insert four catheters into the heart via the leg veins. Some of these catheters are used for ablation, while others are used for advanced imaging techniques, such as such as image integration, a technology we helped develop that blends high-quality images of a patient’s anatomy into the actual procedure. Our imaging specialists use X-ray, ultrasound and image integration to visualize the catheters inside the heart. All of these advanced imaging tools provide 3-D mapping ability which helps our physicians guide the catheters in a safe and effective manner.

What Is the Difference Between Paroxysmal and Persistent Atrial Fibrillation?

Treatment is determined according to the type of atrial fibrillation, including:

• Paroxysmal atrial fibrillation. This condition is associated with recurring episodes of atrial fibrillation that start and stop on their own without requiring medication or electrical cardioversion. Paroxysmal atrial fibrillation is usually initiated by rapid electrical firing from the pulmonary veins, and pulmonary vein isolation is typically an effective treatment
• Persistent atrial fibrillation. When the condition progresses, some patients go into persistent atrial fibrillation. This means that their episodes do not terminate spontaneously, and they usually require antiarrhythmic medication or electrical cardioversion to stop an episode. In these patients, there are areas in the left atrium (in addition to the pulmonary veins) that play a role in initiating and sustaining atrial fibrillation. As a result, treatment involves pulmonary vein isolation as well as ablation of other abnormal areas in the left atrium which may play an important role in causing susceptibility to atrial fibrillation

How Safe Is Catheter Ablation for Atrial Fibrillation?

The success rate of the procedure is generally very good, and depends on many factors, such as the duration of the condition, the presence of valve disease or coronary artery disease, the type of atrial fibrillation (paroxysmal or persistent) and the size of the atria.

However, like any other invasive procedure, rare complications can occur. These complications include perforation of the heart, stroke, heart attack, narrowing of the pulmonary veins, bleeding at the entry site in the leg, and rarely, esophageal injury. Your physician will discuss all of these topics with you during your pre-procedure office visit.

What to Expect

What to Expect the Night Before the Procedure

A nurse from the Electrophysiology Lab at Mass General will call you the evening prior to the procedure. The nurse will give you instructions about your medications and what time to arrive at the hospital. You may have nothing to eat or drink, including pills after midnight the day of the procedure.

What to Expect the Day of the Procedure

Once you arrive at the hospital you will first check into the Admitting Office. You will then report to the Electrophysiology Lab (Gray 109 across from Coffee Central). The catheter ablation procedure can last up to six hours. This time includes preparation to start the procedure as well as time needed to get you ready to go to your assigned bed at the conclusion of the procedure.

In a small number of our patients an ultrasound of the heart is needed to make sure that there is no blood clot present. This is called a transesophageal echocardiogram (TEE) and is done when the INR has not been therapeutic before the procedure. The TEE involves a probe that goes down your throat to look at your heart. You will be given sedation during this test. If there is any evidence of a blood clot the procedure may be postponed to a later date. Please note that if you require a TEE prior to your ablation, there will be an additional one and a half hours added to your total procedure time.

Because of the length of the procedure and the volume of fluid that you receive during the procedure, a catheter will be placed in your bladder prior to the start of the case. If there is a medical reason why you cannot have a catheter, please let a nurse know.

The catheter ablation is done under general anesthesia or procedural sedation. The type of anesthesia is determined when you meet your physician in the office before the procedure and depends on many factors, including specific type of ablation, the presence of other medical problems, patient’s preference and others. Once the procedure is complete, you will be brought to a recovery room where you will have to lie flat for two to four hours before heading home later that day. Please know the majority of our patients are able to tolerate this procedure without any significant problems. We look forward to making your experience a comfortable one.