WATCHMAN FLX™ in Clinical Trial at MedStar Heart & Vascular Institute

Study of Stroke Prevention Device Which May Give Physicians More Flexibility in Optimal Cardiac Positioning


Washington, D.C., June 12, 2018 – MedStar Heart & Vascular Institute physicians participating in a clinical trial have become the first in the Mid-Atlantic region to implant the next generation of a potentially life-changing device proven to reduce the risk of stroke in certain patients with atrial fibrillation (AFib).

Watchman Notice

The next-generation device, called the WATCHMAN FLX™, is being studied for its ability to provide doctors with greater flexibility and safety while positioning the device in the left atrial appendage, a sub-chamber of the heart where blood can pool and form clots. Those clots may then escape into the circulatory system and block blood flow to brain tissue.

“Our participation in this clinical trial is an example of how the comprehensive AFib program at MedStar Heart & Vascular Institute at MedStar Washington Hospital Center is providing patients with access to cutting-edge devices and treatments before they are widely available,” said Manish Shah, MD, director of the Clinical Cardiac Electrophysiology Fellowship Training Program at the Hospital Center and principal investigator for the new trial.

MedStar Heart &Vascular Institute is one of approximately 40 sites in the U.S. selected for WATCHMAN FLX implantation, and Dr. Shah is currently the leading implanter of devices nationwide.

AFib is the most common cardiac arrhythmia in adults, affecting more than five million Americans, and is expected to become even more common as the population ages. AFib causes about 20 percent of all strokes, and strokes from AFib are particularly severe and twice as likely to cause death or incapacitation compared to strokes from other causes.

Blood thinners are commonly prescribed to patients with AFib to reduce their risk of stroke, but patients and their physicians often have reservations about these types of drugs because of bleeding risks, especially in those patients with an increased risk of falls, along with the potential for medication interactions. As a result, up to 45 percent of patients with AFib may go untreated and unprotected from stroke.

WATCHMAN FLX is designed to prevent the movement of blood clots formed within the left atrial appendage into the bloodstream, thereby protecting patients from AFib-related strokes.

“Atrial fibrillation and its consequences are a growing epidemic, especially as our population ages,” said Stuart F. Seides, MD, physician executive director, MedStar Heart & Vascular Institute. “The refinement of a tool that may prevent strokes more securely in more patients is welcome.”

The first version of WATCHMAN™ became available internationally in 2009, and since then various generations of the device have been implanted more than 50,000 times.

Patients or physicians interested in learning more about this study and possible participation, please contact clinical study coordinator, Roshila Mohammed, at 202-877-0805.


About MedStar Heart & Vascular Institute
MedStar Heart & Vascular Institute is a national leader in the research, diagnosis and treatment of cardiovascular disease. A network of 10 hospitals and 150 cardiovascular physicians throughout Maryland, Northern Virginia and the Greater Washington, D.C., region, MedStar Heart also offers a clinical and research alliance with Cleveland Clinic Heart & Vascular Institute, the nation’s #1 heart program. Together, they have forged a relationship of shared expertise to enhance quality, improve safety and increase access to advanced services. MedStar Heart & Vascular Institute was founded at MedStar Washington Hospital Center, home to the Nancy and Harold Zirkin Heart & Vascular Hospital. Opened in July 2016, the hospital ushered in a new era of coordinated, centralized specialty care for patients with even the most complex heart and vascular diagnoses.

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New Device Reduces Stroke Risk for Certain A-Fib Patients

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.  

Tune in to the full podcast about the WATCHMAN device with Dr. Manish Shah.

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.

Tune in to the full podcast with Dr. Shah.


View the WATCHMAN story featured on WUSA-TV (Channel 9).





First in Northeast Region to Implant Investigational Stroke-Reducing Device

Washington, D.C., March 9, 2017 – MedStar Heart & Vascular Institute at MedStar Washington Hospital Center became the first facility in the Northeast region to implant an investigational device designed to prevent stroke in patients with atrial fibrillation (A-fib) or an abnormal heart rhythm.  

The electrophysiology team–Manish Shah, MD and Sarfraz Durrani, MD– implanted the AMPLATZER™ Amulet investigational device, as part of a nationwide clinical trial to evaluate the device’s safety and effectiveness. The Amulet works by sealing off the left atrial appendage (LAA), a small area of the heart, where blood clots form and migrate into the bloodstream, potentially causing a stroke.  

“The Amulet left atrial appendage closure system is a new device that may potentially offer protection to our patients at high risk of stroke who are poor candidates for blood thinning medications,” said Dr. Shah, who is the principal investigator of the Amulet trial and director of the Clinical Cardiac Electrophysiology Fellowship Training Program at MedStar Washington Hospital Center.  

In some patients with A-fib, the LAA does not contract effectively and it can become a source of blood clots. These clots can then be released into the heart and enter the bloodstream, where they can travel to the brain and cause a stroke. Currently, patients with A-fib are often prescribed blood-thinning medication, but this treatment option comes with a lifetime of medical management and the risk of major bleeding. By closing the LAA with the Amulet, physicians can block off the LAA and potentially reduce the risk of stroke.    

Patients enrolled in the clinical trial are randomly assigned to receive either the AMPLATZER™ Amulet or the WATCHMAN™, the only FDA-approved LAA closure device in the control arm of the study. The main difference between the two devices is that Amulet does not require patients to take blood thinners for 45 days after implantation.  

In the meantime, WATCHMAN has been a game-changer to protect A-fib patients from stroke. After WATCHMAN gained its FDA approval, MedStar Washington Hospital Center became the first facility in the Washington region to implant the device. To date, more than 100 patients have been outfitted with the WATCHMAN devices. That’s more implants than any other institution on the Mid-Atlantic seaboard. 

How the WATCHMAN™ Device Reduced Stroke Risk for A-fib Patient Connie Wiley

It’s been just over a year since the specialists at MedStar Washington Hospital Center implanted the WATCHMAN device in Connie Wiley, a grandmother of six from Woodbridge, Virginia, and she is feeling better than ever. Connie was one of the first patients in the world to receive this treatment, used to reduce the risk of stroke in patients with atrial fibrillation (A-fib), and since her procedure, we have performed more than 50 WATCHMAN procedures —the most in the Mid-Atlantic region.

If you're like Connie, you have had the shadow of atrial fibrillation and its associated complications looming over you. Atrial fibrillation (A-fib) is an arrhythmia of the upper two chambers of the heart. Because the blood flow from the atria to the ventricles in the heart is compromised due to an irregular heartbeat, blood pools (and consequently can clot) in the atria. In the past, the most common treatment for A-fib was a blood thinner, such as warfarin. However, the main problem with long-term blood thinner use is the risk of internal bleeding.

With atrial fibrillation, the risk of heart attack and stroke increases exponentially. Even blood thinners used to combat the clotting can have their own set of difficulties. However, the WATCHMAN gives hope to those who want complete freedom from some of the potential problems and complications of both A-fib and the medications used to treat it.

Connie's Story

As an avid gardener and grandmother of six, Connie hardly fits the image of a massive coronary and three-time stroke survivor. Looks, however, can be deceiving. A-fib was dragging Connie down, sapping her energy and leaving her feeling tired and unable to function at an optimal level.

“I am an active person, and I wanted to do things,” Connie reflected. “But my body wouldn’t let me do them.”

Not only was she feeling fatigued, her condition was also leading to strokes that could have eventually been fatal. But with a great team of cardiologists and other specialists on her side, Connie was able to reclaim her active lifestyle without the worry of another stroke on the horizon.

“If it wasn’t for them, I wouldn’t even be here,” she said.


The doctors at the MedStar Heart & Vascular Institute, located at MedStar Washington Hospital Center in Washington, D.C., gave Connie a new lease on life after her third stroke, caused by a blood clot that formed due to her atrial fibrillation. It was determined that Connie would be an excellent candidate for receiving an innovative device called the WATCHMAN. For the region, this procedure was the first of its kind. For Connie, she was one of the first WATCHMAN patients in the world.

Using minimally invasive techniques, surgeons introduced the WATCHMAN into her heart, closing off the left atrial appendage (LAA), the area in which most major clots in atrial fibrillation patients develop.

Life, Renewed

After she received the WATCHMAN, Connie almost instantly noticed an increase in her energy level -- she was able to start doing all of the things she'd thought she wouldn't ever be able to enjoy again. One of her biggest victories — and perhaps the moment she knew things were looking up — was when she was able to water her garden the evening of her return home following the implantation of her WATCHMAN device.

One Year Later

Just over a year after her procedure, Connie is feeling better than she has in a long time. Her energy continued to increase following her procedure, allowing her to resume all of her beloved activities. “Not only do I have energy now, I have peace of mind, knowing that I’m not going to stroke,” Connie shared.

At times, Connie's life can become complicated and stressful. Many of these instances would have spelled disaster before the WATCHMAN, precipitating the possibility of another stroke event. The WATCHMAN has allowed her to sail through each challenge without the worry of clots leaving the LAA and traveling to her brain again.

Another advantage Connie is quick to point out is that she has also been able to discontinue her blood thinners, making the possibility of a bleeding event almost nonexistent. Although they can be the difference between life and death for many patients, blood thinners can heighten the risk of bleed-out from even the slightest bumps and bruises — many of which Connie experiences chasing after her six wonderful grandchildren.

If you suffer from atrial fibrillation and are at an increased risk for stroke, you may want to consider the option of the WATCHMAN. By taking control of your A-fib and its associated risks, you, just like Connie, can take your life back and live it on your terms.

Have questions?

We are here to help! If you have any questions about MedStar Washington Hospital Center, call us at 202-877-3627.

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