Atrial Fibrillation Facts
Atrial fibrillation (A-fib) is the most common arrhythmia—or abnormal heart rhythm—in the United States today, affecting between 2.7 and 6 million adults. Why such a wide ranging estimate? While some patients report debilitating symptoms from A-fib—including strong palpitations that feel like a fish flip-flopping in their chest—others only experience shortness of breath, fatigue or less energy than usual. And some have no symptoms at all. As a result, many people with A-fib have yet to be diagnosed and, by extension, treated.
Unfortunately, A-fib puts people at a five times greater risk of stroke than the general population, especially if they’re also 65 and older with high blood pressure. Put another way, 20 percent of all A-fib patients will eventually have a stroke. Even more alarming, strokes from A-fib are more severe than those arising from other causes and twice as likely to cause death or debilitation.
That’s the most worrisome aspect of A-fib for heart specialists everywhere, and why stopping blood clots from forming through blood thinners is our typical first line of defense. Not everyone can tolerate the powerful medications and their side effects, however, especially those who are at high risk of dangerous internal bleeds. As a result, those patients, who may account for up to 45 percent of all people with A-fib, are left unprotected from stroke.
But a novel, new device called WATCHMAN™ has given such patients a safe and effective alternative.
How does the WATCHMAN work?
WATCHMAN works by blocking the source of most strokes caused by A-fib: the left atrial appendage (LAA). Basically a pouch extending from the left top chamber of the heart, the LAA acts like a reservoir where blood can pool and cluster into clots which can then migrate into the bloodstream. If a clot reaches the brain and gets stuck, it causes a stroke.
During a WATCHMAN procedure, we thread a catheter—a thin, plastic tube— up through your groin to the heart, and then deposit the self-expanding device at the entrance to the left atrial appendage.WATCHMAN’s mesh-like filter, shaped like a parachute, then traps clots inside the LAA where they can do no harm. Over time, the body lays down scar tissue over the device, effectively sealing off the LAA forever.
WATCHMAN received FDA approval in the summer of 2015, following two large, well-constructed national trials that I and my colleagues at MedStar Washington Hospital Center, hub of the MedStar Heart & Vascular Institute, participated in. Study findings and subsequent experience have shown that WATCHMAN is just as good as blood thinners in preventing strokes, with the additional benefit of protecting against bleeding in the brain, the most serious risk associated with such traditional anticoagulants as Warfarin and Coumadin.
Experienced WATCHMAN site
Our team has performed more than 100 WATCHMAN procedures to date (the largest volume on the mid-Atlantic seaboard) with the same great results. Minimally invasive, the procedure is safe, simple and effective, generally taking less than an hour. It’s also easy on patients, who go home the day after the procedure with no pain or discomfort.
WATCHMAN is currently only approved for patients who have atrial fibrillation not caused by a valvular problem, so not everyone is eligible. Furthermore, candidates for the procedure must be able to tolerate a short-term treatment with blood thinners for about 45-days. While that’s a drop in the bucket compared to the life-long blood thinning regimen other A-fib patients face, it’s still enough to rule out individuals with a very high risk of bleeding.
Fortunately, new developments are occurring all the time. Right now, we’re studying an investigational device similar to WATCHMAN but without the 45-day blood-thinner requirement. If approved, the new device, called “Amulet,” could widen the field of patients eligible for these clot-trapping mechanisms.
In the meantime, WATCHMAN’s been a game-changer in how we manage certain high-risk A-fib patients and protect them from stroke. With the aging of the U.S. population and an attendant rise in people with A-fib, WATCHMAN and similar devices will play an ever larger role in the years ahead.
View the WATCHMAN story featured on WUSA-TV (Channel 9).