Cardiac Ablation Atrial Fibrillation
Atrial fibrillation ablation is a procedure used to treat an irregular heart rhythm (arrhythmia) that starts in the heart's upper chambers (atria). It's a type of cardiac ablation, which works by scarring or destroying tissue in your heart to disrupt faulty electrical signals causing the arrhythmia.
Atrial fibrillation ablation may be used if medications or other interventions to control an irregular heart rhythm don't work. Rarely, it's the first choice of treatment for atrial fibrillation.
Treatment for atrial fibrillation usually improves your symptoms, such as fatigue and shortness of breath. Without treatment, atrial fibrillation tends to get worse over time.
Types of atrial fibrillation ablation
The type of atrial fibrillation ablation procedure you have depends on what's causing your irregular heart rhythm and whether you have other heart conditions. Three types of atrial fibrillation ablation are:
· Catheter ablation. The doctor threads long, thin tubes (catheters) into the heart and applies heat or extreme cold. This causes tiny scars in certain parts of the heart muscle, which disrupt or eliminate the erratic electrical signals in your heart. You may also hear the procedure called pulmonary vein isolation, which is a type of catheter ablation.
· Maze procedure. Maze is an ablation technique done during open-heart surgery. Your doctor creates a pattern (maze) of scar tissue in the upper chambers of your heart, using a scalpel or an ablation device. As with catheter ablation, the scarring disrupts the stray electrical signals that cause some types of arrhythmia.
The maze procedure may be right for you if your atrial fibrillation doesn't respond to other treatments or if you're also undergoing other necessary heart surgery, such as coronary artery bypass surgery or heart valve repair.
· AV node ablation. With atrioventricular (AV) node ablation, your doctor uses catheters to create scarring in an area of your heart called the AV node. This is the point connecting the upper chambers (atria) and lower chambers (ventricles). The scar tissue prevents the atria from sending faulty electrical impulses to the ventricles.
AV node ablation may be a good option for you if your atrial fibrillation doesn't get better with other treatments. You may also need a pacemaker to regulate your heart rhythm after an AV node ablation.
How it works
Each beat of your heart is triggered by an electrical impulse normally generated from special cells in the upper right chamber of your heart (pacemaker cells). These signals are faulty in people who have atrial fibrillation, firing so rapidly that the upper chambers of your heart quiver (fibrillate) instead of beating efficiently. These rapidly discharging triggers are called hot spots. To restore a normal heart rhythm, the sources of these hot spots must be isolated from the rest of the heart.
The most common technique for treating atrial fibrillation is catheter ablation. In this procedure, your doctor threads one or more long, thin tubes (catheters) through blood vessels to your heart. He or she uses a mapping catheter to determine where the triggers are located and then applies extreme cold or heat with the catheter tips to destroy (ablate) these spots. This causes scarring that disrupts the faulty electrical signals and restores normal heart rhythms.
The use of extreme cold to cause scarring (cryoablation) is a newer technique. The doctor runs a catheter from the groin to the area of the heart where the arrhythmia originates. He or she then uses it to deploy and inflate a tiny balloon that freezes the area. The result is scar tissue that stops the firing pathway of the faulty signals. This technique takes less time than heat ablation and may have similar risks and complications.
Types
Why it's done
Atrial fibrillation ablation is used to reduce signs and symptoms and improve quality of life. It may be an option for people whose heart quiver (fibrillation) can't be corrected with medication or other treatments. Your doctor might even suggest this procedure before trying medications if, for example, you want to correct the problem without the risk of medication side effects.
About atrial fibrillation
During atrial fibrillation the heart's two upper chambers (atria) beat chaotically and irregularly — out of coordination with the two lower chambers (ventricles). People with this heart condition may feel pounding in the chest (palpitations), shortness of breath and weakness. This condition can also put them at increased risk of a stroke. The condition often gets worse over time if left untreated.
Risks
The risks of atrial fibrillation ablation vary depending on whether you are undergoing a catheter ablation or open-heart surgery, which is less common. Risks include:
· Bleeding or infection at the surgical site or where your catheter was inserted
· Damage to your blood vessels
· Puncture of your heart
· Damage to your heart valves
· Damage to your heart's electrical system, which could worsen your arrhythmia and require a pacemaker to correct
· Blood clots in the legs or lungs (venous thromboembolism)
· Stroke or heart attack
· Narrowing of the veins that carry blood between your lungs and heart (pulmonary vein stenosis)
· Death in rare cases
Discuss the risks and benefits of atrial fibrillation ablation with your doctor to understand if it's right for you.
How you prepare
Your doctor will examine you and order several tests to evaluate your heart condition. He or she will discuss with you the risks and benefits of your atrial fibrillation ablation procedure. Let your doctor know about allergies or reactions you've had to medications. And tell him or her if you're pregnant or planning to become pregnant.
You'll need to stop eating and drinking the night before your procedure. If you take any medications, ask your doctor if you should continue taking them before your procedure. In some cases, you'll be instructed to stop taking medications to treat a heart arrhythmia several days before your procedure.
If you have an implanted heart device, such as a pacemaker or implantable cardioverter-defibrillator, talk to your doctor to see if you need to take any special precautions.
What you can expect
The most common method of atrial fibrillation ablation is catheter ablation. Other types are AV node ablation and the maze procedure, which is done during open-heart surgery.
During catheter ablation for atrial fibrillation
Catheter insertion points for cardiac ablation
Catheter ablation for atrial fibrillation is performed in a hospital. Before your procedure, a specialist will insert an intravenous line into your forearm or hand, and you'll be given a sedative to help you relax. In some situations, a general anesthetica may be used instead to place you in a sleep-like state.
After your sedative takes effect, your doctor or another specialist will numb a small area near a vein on your groin, neck or shoulder. Your doctor will insert a needle into the vein and place a tube (sheath) through the needle.
Your doctor will thread catheters through the sheath and guide them to several places within your heart. Your doctor may inject dye into the catheter, which helps him or her see your blood vessels and heart using X-ray imaging. The catheters have electrodes at the tips that can be used to send electrical impulses to your heart and record your heart's electrical activity. This process of using imaging and other tests to determine what's causing your arrhythmia is called an electrophysiology (EP) study.
Next your doctor uses the catheter tips to apply heat (radiofrequency ablation) or cold (cryoablation) to the target area to destroy tissue and cause scarring.
The procedure usually takes three to six hours. Complicated procedures may take longer.
During the procedure it's possible you'll feel some minor discomfort when the dye is injected in your catheter or when energy is run through the catheter tips. If you experience any type of severe pain or shortness of breath, let your doctor know.
After catheter ablation for atrial fibrillation
Following your procedure, you'll be moved to a recovery area to rest quietly for four to six hours to prevent bleeding at your catheter site. Your heartbeat and blood pressure will be monitored continuously to check for complications.
Depending on your condition, you may be able to go home the same day as your procedure. If you go home the same day, plan to have someone drive you.
You may feel a little sore after your procedure, but the soreness shouldn't last more than a week. You'll usually be able to return to your normal activities within a few days after undergoing cardiac catheter ablation.
Results
Atrial fibrillation ablation may reduce the signs and symptoms of your heart rhythm problem and improve your quality of life. But it hasn't been shown to reduce your risk of a stroke, so your doctor may recommend that you continue blood-thinning medications.
Your irregular heart rhythm may recur, sometimes as long as three years later. Recurrence is more likely in older people and in those with other heart conditions, high blood pressure or a history of difficult-to-treat atrial fibrillation.
You'll likely have a follow-up appointment with your doctor about three months after surgery. If your atrial fibrillation does come back, you may now be able to control it with medications. Some people need another ablation procedure. The Heart Rhythm Society and American College of Cardiology recommend that you heal for at least three months before having a repeat procedure.
Even after successful ablation, your doctor may suggest that you use a continuous heart rhythm monitoring device, such as an implantable loop recorder. If you continue to have heart rhythm problems, your doctor may recommend a permanent pacemaker.
Atrial Fibrillation Ablation
What is ablation for atrial fibrillation?
Ablation is a procedure to treat atrial fibrillation. It uses small burns or freezes to cause some scarring on the inside of the heart to help break up the electrical signals that cause irregular heartbeats. This can help the heart maintain a normal heart rhythm.
The heart has 4 chambers. There are 2 upper chambers called atria and 2 lower chambers called ventricles. Normally, a special group of cells begin the signal to start your heartbeat. These cells are in the sinoatrial (SA) node in the upper right atrium of the heart. During atrial fibrillation, the signal to start the heartbeat doesn’t begin in the sinoatrial node the way it should. Instead, the signal is sidetracked and begins somewhere else in the atria, triggering a small region at a time. The atria can’t contract normally to move blood to the ventricles. This causes the atria to quiver or “fibrillate.” The disorganized signal spreads to the ventricles, causing them to contract irregularly and sometimes more quickly than they normally would. The contraction of the atria and the ventricles is no longer coordinated, and ventricles may not be able to pump enough blood to the body.
For ablation, a doctor puts catheters (thin hollow tubes) into a blood vessel in the groin and threads it up to the heart giving access to the inside of the heart. The doctor then uses the catheters to scar a small area of the heart by making small burns or small freezes. In the burning process, a type of energy called radiofrequency energy uses heat to scar the tissue. The freezing process involves a technique called cryoablation. Scarring helps prevent the heart from conducting the abnormal electrical signals that cause atrial fibrillation.
Sometimes doctors use a surgical approach instead. This is most common when a person is already having heart surgery for another reason.
Why do I need ablation?
Some people have unpleasant symptoms from atrial fibrillation, like shortness of breath and palpitations. Atrial fibrillation also greatly increases the risk of stroke. Anticoagulant medicines used for preventing stroke pose their own risks, and people on certain anticoagulation medicines require extra blood draws and monitoring. The main reason for ablation is to control symptoms. It is not intended to eliminate the need for blood thinners for stroke prevention.
Many people with atrial fibrillation take medicines to help control their heart rate or their heart rhythm. Some people respond poorly to these medicines. In such cases, the doctor may suggest ablation to correct the problem.
Ablation may be more likely to work long-term if you have atrial fibrillation that has lasted for 7 days or less. It may be less likely to work long-term if you have more persistent atrial fibrillation. Ablation might be a good option for you if you have no other structural problems with your heart. It also might be a good option for you if you have symptoms from your atrial fibrillation.
Currently, healthcare providers treat most people with medicine before considering ablation but ablation can be considered a first line alternative to heart rhythm medicine. Ask your doctor about the pros and cons of the procedure in your particular situation.
What are the risks for ablation?
You may have specific risks based on your specific medical conditions. Be sure to discuss all your concerns with your healthcare provider before your ablation. Most people who have atrial fibrillation ablation have a successful outcome. There are some risks associated with the procedure, however. Although rare, there is the risk of death. Other risks include:
- Bleeding, infection, and pain from the catheter insertion
- Damage to the blood vessels from the catheter
- Puncture to the heart
- Damage to the heart, which might require a permanent pacemaker
- Blood clots, which might lead to a stroke
- Narrowing of the pulmonary veins (veins that transport blood from the lungs to the heart)
- Radiation exposure
You are more likely to have complications if you are older or if you have certain other medical and heart conditions.
Another risk is that the procedure may not permanently eliminate atrial fibrillation. Sometimes atrial fibrillation will come back shortly after the procedure or several months later. You might be more likely to have this problem if you are older, have other heart problems, or have a longer duration of atrial fibrillation. Performing the ablation again can permanently eliminate atrial fibrillation in some of these people.
How do I prepare for an ablation?
Talk with your doctor about what you should do to prepare for your atrial fibrillation ablation. Avoid eating or drinking anything before midnight of the day of your procedure. Follow your doctor’s instructions about what medicines to take before the procedure. Don’t stop taking any medicine unless your doctor tells you to do so.
Your doctor might order some tests before your procedure. These might include:
- Electrocardiogram (ECG), to analyze the heart rhythm
- Echocardiography (Echo), to evaluate heart structure and function
- Stress testing, to see how the heart responds to exercise
- Blood tests (for example, to test thyroid levels)
- Cardiac catheterization or coronary angiography, to get more information about the coronary arteries
- Cardiac CT or MRI, to further evaluate your heart anatomy
Let your doctor know if you are pregnant before having the procedure. Ablation uses radiation, which may be a risk to the fetus. If you are a woman of childbearing age, your doctor may want a pregnancy test to make sure you aren’t pregnant.
Someone will shave your skin above the area of operation (usually in your groin). About an hour before the operation, you will be given medicine to help you relax.
What happens during ablation?
Talk with your doctor about what to expect during your ablation. The procedure usually takes 3 to 6 hours. A cardiologist and a special team of nurses and technicians will do the ablation. During the procedure:
- You may have a local anesthetic (numbing medicine) applied to your skin where the team will make a small incision (usually in your groin).
- Or, you may receive a general anesthetic (numbing medicine) with a breathing tube inserted to make you sleep through the surgery.
- Your doctor will make several small holes in a vessel here. He or she will put a few tapered tubes called sheaths through this hole.
- Your doctor will put a series of electrode catheters through the sheaths and into your blood vessel. (Electrode catheters are long, thin, flexible tubes with electrodes at the tip.) The team will then advance the tubes to the correct place in your heart.
- Next, the doctor will locate the abnormal tissue using special technology. He or she will do this by sending a small electrical impulse through the catheter. Other catheters will record the heart’s signals to find the abnormal sites.
- The doctor will place the catheter at the site where the abnormal cells are. He or she will then scar the abnormal area (by freezing or burning). This might cause slight discomfort.
- The team will remove the tubes. They will close your vessel with firm pressure.
- The team will close and bandage the site where the doctor inserted the tubes.
What happens after ablation?
Talk with your doctor about what to expect after your ablation. In the hospital after the procedure:
- You will spend several hours in a recovery room.
- The team will monitor your vital signs, such as your heart rate and breathing.
- You will need to lie flat for several hours after the procedure. You should not bend your legs. This will help prevent bleeding.
- Most people spend the night in the hospital.
- You may feel some chest tightness after the procedure.
- Your doctor will review which medicines you need to take, including blood thinners.
At home after the procedure:
- Most people can return to normal activities within a few days after leaving the hospital.
- Avoid heavy physical activity for a few days.
- Avoid driving for 48 hours after the procedure.
- You may have a small bruise from the catheter insertion. If the insertion site starts to bleed, press down on it and call your doctor.
Call your doctor if your leg is numb or if your puncture site swells. Also call your doctor if you have chest pain, an irregular heartbeat, or shortness of breath.
After you leave the hospital, it is important to follow all the instructions your healthcare provider gives you for medicines, exercise, diet, and wound care. Be sure to keep all your follow-up appointments.