Radiofrequency Treatment of Atrial Fibrillation: Early Success Declines Over Time
Radiofrequency ablation is not always a permanent fix for patients with AFib.
It’s pretty amazing that doctors can thread electrodes into the heart and use radiofrequency energy to zap away a troublesome heart rhythm. But more and more people with atrial fibrillation—the most common type of irregular heart rhythm—are having the procedure done, rather than take lifelong medication.
The problem is that the heart changes over time, so the irregular rhythm can reappear. As a result, doctors haven’t known whether radiofrequency ablation, as the zapping procedure is known, was a long-term solution or just a quick fix.
Now a study published in the January 4 issue of the Journal of the American College of Cardiology provides an answer. It turns out that in order to successfully eliminate atrial fibrillation, patients and cardiologists often have to be even more persistent than the arrhythmia itself. After 5 years of follow-up, researchers found that 63 percent of people who had the procedure were free of atrial fibrillation, but more than half needed at least one repeat radiofrequency procedure to achieve that goal.
The new study involved 100 patients who had radiofrequency ablation for atrial fibrillation at a hospital in Bordeaux-Pessac, France. All of the patients had experienced the irregular heart rhythm for at least six months and were not responding well to medications.
During the procedure, cardiologists threaded special electrodes into the left atrium, one of the heart’s upper chambers. They then created a map of the tissue causing the abnormal electrical impulses and treated it with repeated bursts of radiofrequency energy to create lines of scar tissue. The scar tissue creates a blockade that prevents the abnormal electrical impulses from spreading to the rest of the heart.
After one, three, six and 12 months, patients returned to the hospital for follow-up. Each time, if tests showed that atrial fibrillation had returned, cardiologists offered to do a repeat radiofrequency ablation procedure. After five years, patients returned to the hospital again for testing.
Researchers found that the likelihood that a single radiofrequency ablation procedure would be effective in eliminating atrial fibrillation was only 40 percent at one year, 37 percent at two years and 29 percent at 5 years. However, with repeat procedures, the success rate climbed to 87 percent at one year, 81 percent at two years and 63 percent at five years. Even with good early success, atrial fibrillation could be expected to return in about 9 percent of patients each year.
Researchers concluded that when patients are deciding whether to have a radiofrequency ablation procedure, they should be told about the slow, steady decline in its effectiveness over time and the need for repeat procedures. Equally important, because early success cannot guarantee long-term success, patients must be retested now and again to make sure the irregular heart rhythm has not returned.
Questions for You to Consider
Why is someone with atrial fibrillation at risk for a stroke?
Normally, blood is constantly flowing through the atria, ventricles and blood vessels. But because blood pools in the quivering atria, it has the chance to congeal into blood clots, which can travel to the brain, blocking blood flow and causing a stroke. That’s why patients with atrial fibrillation must take some form of anti-clotting medication such as aspirin or the blood thinner warfarin (Coumadin).
Not wanting to take lifelong blood thinners is one of the reasons people have radiofrequency ablation to rid themselves of atrial fibrillation. However, researchers in the new study advised anyone who has already had a stroke to continue taking blood thinners, since atrial fibrillation can return even after a successful radiofrequency ablation procedure.
- What is it like to have a radiofrequency ablation procedure?
The procedure will be done in the hospital, in the electrophysiology (EP) laboratory. You’ll be awake during the procedure but you’ll be given a sedative to help you relax. Your heart and blood pressure will be monitored the entire time.
While you lay flat on a table in the EP lab, your cardiologist will insert a needle into a vein in your groin (or possibly your arm or neck), after first numbing the area. Then slender tubes called catheters will be threaded through your veins into your heart. The catheters have special electrodes on their tips that can detect abnormal electrical impulses in your heart and send out pulses of radiofrequency energy to destroy problem tissue and leave scar tissue in its place.
The radiofrequency ablation procedure takes several hours, depending on how many areas of the heart are generating abnormal electrical impulses. Your cardiologist will carefully create lines of scar tissue around each of them. You may feel some discomfort when the catheter is sending out radiofrequency energy. Be sure to let your doctor know if you feel severe pain or shortness of breath.
After the procedure, you’ll need to lie to flat on a bed for several hours while pressure is applied to the puncture site in your groin. This helps a blood clot to form. During this time, it’s important not to move your legs, sit up or walk around. Depending on how you’re doing, your doctor will decide whether you should go home or stay in the hospital overnight. You may feel some abnormal heart beats after the procedure, but these should go way once your heart has healed.