What is a Watchman (Left Atrial Appendage Closure) device?

From the Guidelines

A Watchman device is a percutaneous left atrial appendage (LAA) occlusion device used to reduce stroke risk in patients with atrial fibrillation who are poor candidates for long-term oral anticoagulation. The device has been compared with warfarin in patients with AF in two randomized controlled trials (RCTs): the PROTECT AF and PREVAIL trials 1. According to the 2019 AHA/ACC/HRS guideline, the Watchman device provides an alternative for patients who are poor candidates for long-term oral anticoagulation due to bleeding propensity or poor drug tolerance or adherence 1.

The device works by permanently sealing off the left atrial appendage, a small pouch in the heart where blood clots commonly form during atrial fibrillation. Key considerations for patient selection include a CHADS2 score ≥2 or a CHA2DS2-VASc score ≥3, as specified by the Centers for Medicare & Medicaid Services (CMS) 1. The procedure involves inserting the device through a catheter in the groin and guiding it to the heart, where it expands to block the appendage. Post-implantation antithrombotic regimens typically involve blood thinners for a period, followed by dual antiplatelet therapy and eventually aspirin alone indefinitely 1.

Some key points to consider when using the Watchman device include:

• The device is an option for patients who are suitable for short-term warfarin but deemed unable to take long-term oral anticoagulation 1
• Patients should be deemed suitable for anticoagulation and, in particular, a period of periprocedural anticoagulation 1
• There is increasing experience outside the United States with LAA closure in oral anticoagulation–ineligible patients using an antiplatelet regimen only 1
• The Watchman device has been shown to reduce hemorrhagic strokes compared to warfarin, but may increase ischemic strokes, although this difference is not significant when periprocedural events are excluded 1

From the Research

Definition and Purpose of the Watchman Device

• The Watchman device is a left atrial appendage occlusion device used to prevent stroke in patients with atrial fibrillation 2.
• It is an alternative to oral anticoagulants for patients with contraindications for anticoagulation 2.
• The device is designed to prevent blood clots from forming in the left atrial appendage, which can increase the risk of stroke in patients with atrial fibrillation.

Comparison with Other Treatments

• The Watchman device has been compared to warfarin and novel oral anticoagulants in terms of efficacy and safety for stroke prevention in nonvalvular atrial fibrillation 3.
• Studies have shown that novel oral anticoagulants are superior to warfarin for stroke prevention, while the Watchman device is a reasonable non-inferior alternative to warfarin 3.
• The device has also been compared to other left atrial appendage occlusion devices, such as the Amplatzer cardiac plug and Amulet, in terms of design, characteristics, and clinical data 4.

Clinical Effectiveness and Safety

• The Watchman device has been shown to be effective in preventing stroke in patients with atrial fibrillation, with a significant reduction in the risk of stroke or systemic embolism 3.
• However, the device has also been associated with complications, such as pericardial effusion and device-related thrombus 5.
• The safety and efficacy of the Watchman device have been evaluated in various studies, including a decision analysis that compared the device to oral anticoagulation in atrial fibrillation 6.

Indications and Patient Selection

• The Watchman device is indicated for patients with nonvalvular atrial fibrillation who are at high risk of stroke and have contraindications for anticoagulation 2.
• Patient selection for the Watchman device should be based on individual risks for ischemic stroke and bleeding, as well as other factors such as age and comorbidities 6.
• The device may be a suitable alternative to oral anticoagulants for patients with high bleeding risk, but the overall benefit depends on the combination of stroke and bleeding risks in individual patients 6.