What Is Ablation of Atrial Fibrillation?
What Is Atrial Fibrillation?
Atrial fibrillation (AF) is a type of heart arrhythmia. An arrhythmia is an irregular heartbeat in rhythm or rate. AF is caused by disorganized electrical impulses originating in the right side of your heart, called the right atrium. The nonconforming electrical signals may cause your atrium to fibrillate, or contract, quickly and in an irregular way. During an AF episode, your heart can beat too quickly, or in an unpredictable pattern.
The term “ablation” comes from the verb “ablate,” meaning “to remove or destroy.” In terms of atrial fibrillation, ablation refers to a treatment option when medication can’t control the irregular electrical activity in the heart. Ablation is a surgical procedure that scars a very small area of heart tissue. The target area scarred is the source of the irregular electrical impulses that cause atrial fibrillation. Once the living tissue is damage or destroyed, it can no longer produce the erroneous electrical signals that lead to an arrhythmia. A number of terms are used for the procedure, all referring to the same type of treatment:
- ablation of atrial fibrillation
- catheter ablation
- pulmonary vein ablation
- radiofrequency ablation
Preparation for Catheter Ablation
Ablation of atrial fibrillation is done in the hospital. You’ll follow specific instructions before the procedure, including:
- blood work to make sure you are healthy enough for surgery
- blood thinning medication for a month before surgery to prevent blood clots
- computed tomography (CT) scans or magnetic resonance imaging (MRI) to examine the veins used in the procedure
- fasting after midnight the day before the ablation
Talk to your doctor about any other medications or dietary supplements you take. You might need to temporarily stop taking them before the ablation as a precautionary measure.
Catheter ablation is performed under conscious sedation. This means you are awake and aware, but not in any pain. After giving you a sedative and local anesthesia, your doctor will insert a catheter—a thin, flexible tube—into a vein in your groin. Sometimes a vein in the neck is used instead. Using a special X-ray called a fluoroscope to see where the catheter is located, he or she will thread the catheter up toward your heart. Once the catheter is in place, your doctor will send radio waves through the tube. The end of the catheter is equipped with a device that heats up from the radiofrequency. Applying the heat to the faulty heart tissue destroys it on contact. Ablation commonly takes several hours to complete.
Minimally Invasive Ablation
A newer, minimally invasive ablation procedure called “Mini-Maze” can also be an effective treatment for atrial fibrillation. Minimally invasive surgery uses smaller incisions and generally does not take as long as conventional procedures. Mini-Maze ablation takes between three and four hours. The surgery is done with tiny incisions on the side of your torso, underneath your armpit. The incisions are just big enough for a camera and the catheter to pass through. As with the standard catheter ablation, radiofrequency kills the atrial tissue that causes AF.
Recovery is relatively quick with either type of ablation for atrial fibrillation. You may stay in the hospital for a day or two so medical personnel can monitor your heart activity. Often, atrial fibrillation symptoms recur during the first few weeks after surgery. This is a normal part of the healing process. Blood-thinning medications help prevent problems such as blood clots. You might also take antiarrhythmic drugs to control stray electrical activity. You can most likely resume your normal activities within a couple of weeks.
Although catheter ablation is safe and effective, any type of surgery carries risks. Blood clots, accidental puncture of the heart, and stroke are all possible complications. According to the journal Circulation, these conditions affect only 1 to 2 percent of the population. Esophageal damage is also a risk because the left atrium of the heart is behind the esophagus. Pulmonary vein stenosis is another potential side effect of ablation. This narrowing of the veins can lead to blood clots and other problems associated with blocked veins.
The success rate of ablation for atrial fibrillation varies widely, depending on the type of AF you have. According to a 2006 issue of Circulation, ablation is effective in 30 to 90 percent of AF patients. People who have rare, intermittent episodes of arrhythmia but do not have other heart problems are more likely to see a significant improvement. Other patients may experience partial improvement with a reduction but not complete elimination of symptoms.
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