WATCHMAN Device Implant for AFib | MedStar Health

WATCHMAN™ Device (Left Atrial Appendage Closure)

Pioneers in a non-surgical procedure to prevent stroke in AFib patients

Twenty percent of strokes are caused by an abnormal heart rhythm known as atrial fibrillation, or AFib. Traditionally, the common treatment for AFib was blood-thinning medication, such as warfarin. However, long-term blood-thinner use raises the risk of internal bleeding.

WATCHMAN™ implant

Close up photo of a Watchman device, which is use to help treat atrial fibrillation.We can now implant a WATCHMAN device to permanently seal off the left atrial appendage (LAA) of the heart, a small pouch that is the site of almost all stroke-causing blood clots in people with AFib. The device is designed to essentially act as a mesh filter, allowing blood to flow through while stopping clots.

We have more experience with this minimally invasive procedure than anyone else in the mid-Atlantic region. The WATCHMAN was the first left atrial appendage closure device approved by the Food and Drug Administration (FDA) for AFib. Our teams in the Electrophysiology and Interventional Cardiology programs tested the device for eight years in multiple clinical trials before it reached the market, and we were the first in the region to use it successfully.

Who is a candidate for WATCHMAN™?

Your doctor may recommend implanting a WATCHMAN device if you:

  • Are at increased risk of stroke and blood-thinning medication is recommended

  • Have atrial fibrillation not caused by a heart valve problem

  • Have a history of bleeding problems while taking blood thinners or are unable to tolerate their side effects

  • Have a medical condition, occupation, or lifestyle that increases your risk of major bleeding due to trauma

  • Have trouble staying within the recommended blood-clotting range

You should not have a WATCHMAN device implanted if you:

  • Are allergic to a material in the device, such as nickel or titanium

  • Can’t take blood thinners

  • Need to take blood thinners for a reason other than AFib

  • Should not or cannot undergo heart catheterization

What to expect from WATCHMAN™?

The procedure will take place in one of our electrophysiology (EP) or cardiac catheterization labs. Here, we have specialized equipment that allows your doctor to test the electrical activity of your heart. You’ll be put to sleep using general anesthesia. Your doctor will make a small incision in your groin and insert a thin, flexible tube called a catheter into a blood vessel. At the end of the catheter is the jellyfish-looking device.

The doctor will guide the catheter to the opening of your left atrial appendage. The WATCHMAN is spring-loaded to expand to about the size of a quarter once placed. There are no batteries or wires, and it’s intended to be left in place permanently.

The procedure will take about an hour and you will need to stay in the hospital overnight. You’ll continue to take blood-thinning medication until scar tissue grows over the device and seals off the LAA. Most patients can stop taking blood thinners within 45 days.

MedStar cardiac surgeons perform a procedure in the MedStar Health cardiac electrophysiology lab.


Atrial fibrillation (AFib)

Atrial fibrillation, or AFib, is a type of arrhythmia (abnormal heartbeat) in which the heart’s two upper chambers do not beat in sync with the two lower chambers.

Computerized tomography (CT) scan

The cardiac computed tomography scan, or cardiac CT, uses X-rays to create three-dimensional images of your heart and blood vessels.


An echocardiogram uses high-frequency sound waves to create images of your heart.

Electrocardiogram (ECG)

An electrocardiogram, also known as an ECG, measures the heart’s electrical activity.

Event monitors

An event monitor is a small device that records the heart’s electrical activity. It’s similar to an electrocardiogram, but where an electrocardiogram takes place over a few minutes, an event monitor measures heart rhythms over a much longer time.

Holter monitors

A Holter monitor is a small device that records the heart’s electrical activity. It’s similar to an electrocardiogram, but whereas an electrocardiogram records over a few minutes, a Holter monitor records over the course of a day or two.

Stress tests 

Stress tests are used to assess how your heart works during physical activity. There are several types of stress tests, including treadmill or bike stress tests, nuclear stress tests, stress echocardiograms, and chemically induced stress tests.

Additional information

Electrophysiology program

We are leaders in developing and using the latest procedures and technologies to treat heart rhythm disorders, and our cardiac electrophysiology laboratory is one of the most sophisticated in North America.

Our locations

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MedStar Union Memorial Hospital

201 E. University Pkwy.
Baltimore, MD 21218

MedStar Washington Hospital Center

110 Irving St. NW
Washington, DC 20010

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