The WATCHMAN FLX to Mitigate Stroke Risk in Non-Valvular Atrial Fibrillation

Atrial fibrillation, or Afib, is the most common heart rhythm disorder, or cardiac arrhythmia, in the US, with upwards of five million Americans suffering from the condition. Patients experiencing Afib have a fast and irregular heartbeat of anywhere from 300 to 600 beats per minute. The result can be anything from uncomfortable to debilitating and downright scary. That said, Afib, in and of itself, is not often considered dangerous in otherwise healthy patients. Instead, the potential follow-on effects of the condition are what we, as cardiologists and electrophysiologists, are most concerned with.

For one, Afib can cause the heart to work significantly harder, resulting in the potential for long-term heart failure. It can also increase the risk of a heart attack by up to five times versus the risk for a patient without the condition. Importantly, Afib patients are also at five times greater risk of stroke, which involves a blood clot traveling from the heart to the brain and occluding essential blood vessels.

How Does Afib Cause Stroke?

Afib is implicated in about 25%1 of all strokes. Data has shown that Afib-related strokes have a substantial risk of disability, a higher risk of mortality, and a greater risk of recurrence than most other types of stroke.

The increased risk of stroke in Afib patients results from a small outpouching of the heart, known as the left atrial appendage or LAA. We don’t fully understand the usefulness of this pocket, but it can cause severe problems for those with Afib. When the heart beats normally, blood enters and leaves the LAA efficiently. However, with the poorly coordinated heartbeat associated with Afib, blood can pool within this chamber. This pooled, stagnant blood can then begin to coagulate. If a piece of coagulated blood breaks off and enters the circulatory system, it can travel to the brain, where it causes a stroke.

Lowering Afib-Related Stroke Risk

When dealing with stroke risk associated with Afib, it is essential to take a measured but urgent approach. After all, strokes are unpredictable, and their consequences are significant. However, we do take a stepwise approach toward their prevention. Ideally, patients would improve their diet, exercise, and lifestyle habits to reduce the risk associated with new or worsened Afib. Poor diet, lack of exercise, and lifestyle habits such as excessive alcohol consumption and smoking can all have deleterious effects. However, most patients do not or cannot change their lifestyles over the long term, necessitating a front-line treatment consisting of medical therapy.

Medical Therapy

Medical therapy for stroke risk associated with Afib revolves around anticoagulant medication, colloquially known as blood thinners. However, these medications do not thin the blood. Instead, they reduce the ability of blood to clot. The result is a reduced risk of blood clots within the LAA and a resultant reduction in the risk of stroke. However, anticoagulant medications have several downsides, including the increased risk of bleeding issues and side effects that can make taking the medication difficult or impossible. Approximately 50% of all patients taking these pills discontinue use for one reason or another.

Enter the WATCHMAN

The WATCHMAN device for left atrial appendage closure is a novel procedural option for patients with non-valvular Afib (atrial fibrillation not caused by a heart valve) that are candidates for oral anticoagulant medications but have a good reason for not taking them. The WATCHMAN is a small parachute-like device held open by a metallic lattice that is sized appropriately for the opening of the LAA.

The procedure is performed in an EP or Cath lab, and patients are put under general anesthesia. The entire procedure takes about an hour or less. During the procedure, a small incision is made in the groin. A minimally invasive catheter is threaded up to the heart through the femoral vein using fluoroscopy or advanced ultrasound technology. Once in the left atrium, the WATCHMAN is deployed and placed over the opening of the LAA.

The WATCHMAN act as a filter, not allowing clots to get out of the opening to the LAA. Over time, the heart’s natural repair mechanism tries to absorb the WATCHMAN by building scar tissue around the device. This further seals the opening to the LAA, which usually takes about 4-6 weeks.

Does WATCHMAN Cure Afib?

The short answer is that WATCHMAN is not a treatment for Afib; instead, it reduces the risk of stroke due to the condition. However, another very effective procedural option using similar catheter technology is also available to address Afib. Known as cardiac catheter ablation, these two procedures are often performed a few weeks apart with great success.

Who can benefit from a WATCHMAN implant?

  • Patients with a CHA2DS2–VASc (stroke risk) score of two or more for men or three or more for women
  • Patients who are candidates for oral anticoagulation medication
  • Patients with a good reason to avoid medical therapy in the form of anticoagulants, either because of a history of bleeding, the risk of future bleeding, or having a lifestyle or work environment that would increase the risk associated with a bleeding event
  • Patients who have not experienced substantial benefit from oral anticoagulation treatment or have drug interactions with oral anticoagulants

The benefits of the WATCHMAN are very real, and over 96% of patients who received the implant were able to discontinue oral anticoagulant medication 45 days after the procedure2

Are There Risks to the WATCHMAN Device?

Yes, as with any procedure or medical device, some risks are associated with WATCHMAN implantation. However, many of these risks can be mitigated with clinical experience – some of the most common considerations that all patients should understand include the following:

  • The WATCHMAN device cannot guarantee with 100% certainty that a clot will not reach the brain. However, the risk of stroke after a successful WATCHMAN implant is exceedingly low
  • A small number of patients will need to continue oral anticoagulant therapy
  • All of the inherent risks associated with anesthesia must be considered
  • The specific risks associated with a catheter-based procedure, including damage to blood vessels and heart tissue, can be mitigated by employing an experienced electrophysiologist
  • Bleeding and infection at the incision site at the groin
  • In rare cases, stroke or death. Studies show that the risk of a significant adverse event was only .5%, with a 99%+ procedure success rate

Insurance considerations

Medicare and many commercial insurance plans cover the implantation of the WATCHMAN device, along with pre-and post-procedure visits and testing. This is, of course, assuming that the primary qualification criteria are met. A typical Medicare patient should expect to pay approximately $2600 in out-of-pocket expenses for their procedure. This may vary depending on specific coverage and supplemental insurance. Commercial insurance coverage will vary between companies and plans and should be verified with your carrier.

To get a complete picture of costs, we encourage you to contact our office and speak to one of our billing specialists.

The Bottom Line

While effective and non-invasive, qualifying patients no longer have to live with the often-significant concerns associated with oral anticoagulants. Upwards of 50% of all patients do not, or cannot, continue on their medication regimen. As an alternative, the WATCHMAN device is implanted using safe, effective, and proven catheter technology and has shown great promise in reducing the risk of stroke in appropriate patients. In part because of this device, the range of tools available to treat A-fib and its resultant risks have never been greater.

Should you suffer from atrial fibrillation or any other arrhythmia / irregular heartbeat, we encourage you to visit the office of Paul Gerczuk, MD for a complete diagnosis and treatment plan. Treating cardiac arrhythmias at their earliest presentation allows for the broadest treatment options. We look forward to seeing you at one of our offices in North Tampa, Wiregrass or WaterGrass and having the opportunity to help you.

About Dr. Paul Gerczuk, MD

As a Cardiac Electrophysiologist, Dr. Paul Gerczuk specializes in the electrical system of the heart and abnormal heart rhythms and is specifically trained to treat them.  Her is board certified in Clinical Cardiac Electrophysiology and Cardiovascular Disease and National Board Certified in Echocardiography. His training includes both medical and procedural treatment of atrial fibrillation and he was the first cardiologist in Tampa Bay to implant 200 WATCHMAN devices.  He is dedicated to providing the best care possible and seeing his patients get their quality of life back to incredibly rewarding to him.

1Perera KS, Vanassche T, Bosch J, Swaminathan B, Mundl H, Giruparajah M, Barboza MA, O’Donnell MJ, Gomez-Schneider M, Hankey GJ, et al; ESUS Global Registry Investigators. A global survey of atrial fibrillation-associated stroke frequency: Embolic Stroke of Undetermined Source Global Registry.Stroke. 2016; 47:2197–2202. doi: 10.1161/STROKEAHA.116.013378

2Kar, S., et al, Primary Outcome Evaluation of the Next Generation LAAC Device: Results from the PINNACLE FLX Trial, Circulation, 2021.



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Paul Z. Gerczuk, MD

Clinical Cardiac Electrophysiology

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