Clinical Trials for Atrial Fibrillation

Medically Reviewed by James Beckerman, MD, FACC on July 08, 2022
5 min read

More people have atrial fibrillation (AFib) than any other kind of irregular heartbeat. And the numbers are only expected to go up as people live longer with heart conditions that go along with it.

Treatment is aimed at controlling your heart’s rate and rhythm, and preventing blood clots that can cause a stroke. Through clinical trials, researchers are constantly working on safer and more effective ways to accomplish those goals. Here are the latest treatments, and what’s on the horizon.

Atrial fibrillation happens because of abnormal electrical signals in parts of your heart. Cardiac ablation stops those signals from triggering irregular beats by damaging the problem areas. The procedure is usually done using a catheter threaded through a major vein into your heart. It can also be done surgically.

Dozens of studies are looking at this procedure. Doctors already have a lot of information comparing it to treatment with drugs alone to control your heart rhythm. But they’re still working to determine when’s the right time to try it, and for which patients it works best.

They’re also trying to find better ways to do the procedure.

Tools.Catheter ablation is usually done either with a tool that generates extreme heat with radio waves, or a tool that generates extreme cold. Manufacturers are testing new kinds of hot and cold catheters. The FDA has already approved a catheter that uses a laser, rather than radio waves, to burn scars onto problem spots on your heart.

A different kind of technology under study is called pulsed field ablation. It uses an electrical current to destroy heart tissue. Early research has shown it to be more precise than traditional hot and cold ablation, causing less accidental damage.

They’re also trying to make the procedure more effective by finding better ways to identify ablation targets. New mapping technology is being tested to more accurately locate the places in your heart that are causing abnormal electrical signals.

Technique. The faulty electrical signals that trigger AFib most often originate in the veins that carry blood from your lungs to the left atrium of your heart. This connection point is the focus of most ablation procedures, in a process called pulmonary vein isolation (PVI). But it often isn’t completely successful the first time.

Researchers are studying the best technique for accomplishing pulmonary vein isolation, and also whether it’s better to also target other areas that can generate electrical signals during the same procedure.

Surgical ablation. Sometimes ablation is done on the outside of your heart, especially if you’re having a different kind of heart procedure at the same time. A newer approach combines surgery on the outside of the heart with catheter ablation on the inside. This hybrid technique is being tested as a treatment for atrial fibrillation that has gone on for a long time. Doctors are also trying to see if it’s better than doing a second pulmonary vein isolation in cases where the first one didn’t work.

Another procedure getting a lot of study is a procedure called left atrial appendage occlusion. When your heart doesn’t beat normally, blood can pool in the upper chambers and form clots. A clot can break loose into your bloodstream, make its way to your brain, and cause a stroke.

Clots tend to form in a part of your heart called the left atrial appendage. Blocking that off can lower your stroke risk.

The FDA recently approved a device called the Amulet. It’s now being compared to a similar device called the Watchman that’s been in use for several years. Different devices to either close or block the left atrial appendage are also being developed.

Researchers are also looking at whether these occlusion devices work better than blood thinners at preventing strokes in people with AFib.

Drugs are used in atrial fibrillation treatment to control your heart rate and heart rhythm, and also prevent blood clots. Researchers are testing new drugs, including biologic blood thinners. They’re also looking at drugs that are already approved for other illnesses to see if they can be useful in managing AFib, like drugs that help people control diabetes.

When it comes to stroke prevention, heart experts now recommend a class of blood thinners called NOACs, or non-vitamin K oral anticoagulants. The newest one approved to treat atrial fibrillation is edoxaban.

An open question in AFib treatment is when to start it. Drugs that control your heart rhythm can have serious side effects, so it may be better to wait until symptoms bother you. On the other hand, the longer you have atrial fibrillation, the more damage it does to your heart and the harder it is to treat. One major study is looking at whether it’s better to start taking the rhythm-controlling drug dronedarone as soon as you’re diagnosed.

Researchers are also studying the role of certain drugs in combination with AFib procedures. They want to know whether ablation is more successful if you keep taking rhythm-controlling drugs for a period of time afterward. And they’re testing what kind of blood thinning strategy works best to prevent blood clots right after a left atrial appendage occlusion.

Smartphone technology is making it easier for you and your doctor to monitor your atrial fibrillation and make treatment decisions. Devices that connect to apps on your phone can alert you when you’re having an episode and send that information to your doctor.

The FDA has cleared the use of smartwatches and other wearable devices for AFib detection from Apple, Samsung, Fitbit, and Withings. Researchers continue testing their effectiveness in helping manage AFib, and other devices are being developed.

You can help advance the science of treating atrial fibrillation by taking part in a clinical trial. The first step is to talk to your doctor to make sure it would be safe for you. They may also know of studies in your area that are recruiting volunteers. The National Institutes of Health has a database at ClinicalTrials.gov where you can search by condition and location.

When you find something that interests you, here’s what you can expect:

  • You’ll talk to someone involved with the study to make sure you qualify. You may need to be in a particular age range or have already tried a certain AFib treatment.
  • You’ll get detailed information about the study before you agree to participate. It will tell you how long the trial will last and how often you’ll have treatment or checkups. Be sure you understand the possible risks and benefits.
  • You’ll get whatever treatment is being tested, or you might get what’s called a placebo. That means you don’t get actual medicine or treatment, so researchers can compare whether the new treatment works better than nothing. You may not know which you got until the study is over.
  • You’re allowed to quit the study at any time.

You can help researchers come up with new atrial fibrillation treatments even if you don’t have it. Some clinical trials include what they call “healthy” volunteers. They help doctors see how a treatment affects people who don’t have a particular illness.