Dr. John Day
Dr. Day is a cardiologist specializing in heart rhythm abnormalities at St. Mark’s Hospital in Salt Lake City, Utah. He graduated from Johns Hopkins Medical School and completed his residency and fellowships in cardiology and cardiac electrophysiology at Stanford University. He is the former president of the Heart Rhythm Society and the Utah chapter of the American College of Cardiology.
Blood Thinners versus Watchman for Atrial Fibrillation: Which is Best?
No one wants an stroke and most of my AFib patients at higher risk for stroke don’t want to take a blood thinner for life. Fortunately, AFib patients at low-risk for stroke don’t require blood thinners. But for those who have to take a blood thinner, are there any alternatives? In this article we’ll discuss AFib strokes, the role of the left atrial appendage, and whether blood thinners or Watchman is best for AFib.
What Causes Atrial Fibrillation Strokes?
Strokes are common in AFib patients because the complete electrical chaos in the atria leads to loss of pumping. The result is stagnant blood flow, and stagnant blood clots easily, especially in the left atrial appendage. The left atrial appendage is a dead end pouch in the left atrium where clots form when atrial fibrillation causes the upper chambers not to pump.
When these clots break off from the left atrial appendage and enter the bloodstream, they are like missiles that can go anywhere in the body and do incredible damage. Clots that go to your gut, kidneys, or leg can all leave a trail of destruction. But when clots go to the brain, resulting in a stroke, the effect is immediate, devastating, and often deadly.
What Happens During a Stroke?
During a stroke, the brain is starved of oxygen and nutrients, a situation that almost immediately begins to kill brain cells. You’ll also recall from previous posts that AFib is usually associated with high blood pressure. That’s a double disaster, since years of high blood pressure can damage the arteries in the brain long before the atrial fibrillation clot ever arrives. For all of these reasons, atrial fibrillation has been associated with a five-fold increase in the risk of stroke.
Those risks aren’t uniform, of course. They increase with age, and also with other complicating medical conditions. But even among AFib patients who are young and relatively healthy in other ways, no one with AFib is safe from stroke. Strokes in patients with atrial fibrillation that do not kill often result in greater disability compared to strokes caused from other reasons. Even “small” strokes over time can impair cognition and greatly increase the risk of dementia.
Why Are Blood Thinners Used for Atrial Fibrillation?
Because atrial fibrillation increases stroke risk, doctors are often keen to prescribe an anticoagulant. These medications, also called blood thinners, help prevent clots from forming inside your heart. And the less likely you are to form a blood clot in your left atrial appendage, which can happen when the upper chambers of the heart stop beating during AFib, the less likely it is that a clot will break off, cutting of the blood supply—and thus the oxygen—to the brain or other organs or structures.
Left Atrial Appendage Closure (Watchman or Amulet devices)
One way to get off blood thinners is having your left atrial appendage closed or removed. The two most popular non-surgical ways to close off the left atrial appendage are with the Watchman device from Boston Scientific or the Amulet device from Abbott Laboratories. Implanting either of these devices in the heart is a relatively simple outpatient procedure through an IV in a leg vein.
Intuitively, it seems this should be an enormously effective solution. After all, approximately 90 percent of all AFib strokes arise from blood clots forming in the left atrial appendage, a small sac in the muscle wall of the left atrium. Many doctors believe closing off this part of the heart, through the insertion of a closure device that plugs the sac’s opening, can keep clots from coming loose and heading toward the brain, where they can get stuck and cause a stroke.
4 Challenges with Left Atrial Appendage Closure (Watchman or Amulet)
But what seems intuitive and what happens in real life can, in some patients, be two different things. Studies show that a left atrial appendage closure device, along with a daily aspirin, offers a survival rate equivalent to blood thinners. However, with these left atrial appendage closure devices, like the Watchman or Amulet, there are some important things to consider.
1. You have a 1 in 50 of developing a blood clot on the device
This is intuitive, too, because any time you stick a foreign object into the circulatory system, the body wants to form a clot, so you may be trading one potential cause of stroke for another. And if you are that 1 in 50 then you may never get off blood thinners.
2. Your cardiologist may increase your stroke risk with a left atrial appendage leak
There is also a small chance that your cardiologist will leave you with a left atrial appendage leak after implanting the Watchman or Amulet devices which means blood can still get in and out of your appendage. This is not a good thing—a leak can dramatically increase your stroke risk even higher than it is right now.
3. Left atrial appendage closure does nothing for AFib
Closing off the left atrial appendage does nothing for your AFib. While it offers stroke protection, you will still have AFib and you will still be at an increased risk of premature death, dementia, and heart failure.
This is an important consideration as our studies have shown that with a successful ablation procedure your long-term stroke risk, as well as your risk of death or dementia, is no different than someone who has never had atrial fibrillation. In other words, based on our experience, a successful ablation could eliminate not only your AFib but all of the other increased risks with AFib as well.
4. Aspirin may be just as risky as a blood thinner
After you get through the healing process of left atrial appendage closure, your cardiologist will still keep you on aspirin daily. While aspirin may seem much safer than a “blood thinner,” studies show that there is no statistical difference in the bleeding risk of aspirin versus the safest blood thinner, Eliquis (apixaban).
Despite the Risks Patients Love the Watchman Procedure
Despite the 4 significant challenges with left atrial appendage closure with either the Watchman or Amulet devices, patients still love this procedure. Blood thinners frighten patients and many patients will do anything to get off these medications.
In my experience of caring for Watchman patients over the years, I have only had one patient who ever regretted having the procedure. And this regret only came after she developed a clot on the Watchman device which later broke free and shut off blood flow to her foot. Fortunately, a very talented vascular surgeon was able to remove the clot in time to save her foot. However, this event made it such that she can never come off her blood thinner.
If you want to learn more about atrial fibrillation, be sure to check out our best-selling book, The AFib Cure. To see one of the cardiologists or EP’s in our practice, please call my team at 801-266-3418. Sorry, telemedicine visits outside of the state of Utah are no longer possible.
Also, if you liked the photo attached to this article, it was one of my mountain running trails until the deep snow came a month ago.
Disclaimer Policy: This website is intended to give general information and does not provide medical advice. This website does not create a doctor-patient relationship between you and Dr. John Day. If you have a medical problem, immediately contact your healthcare provider. Information on this website is not intended to diagnose or treat any condition. Dr. John Day is not responsible for any losses, damages or claims that may result from your medical decisions.