From the Guidelines
After Watchman device placement, the recommended anticoagulation regimen typically involves warfarin plus aspirin 81-100mg daily for 45 days, followed by dual antiplatelet therapy (DAPT) with clopidogrel 75mg daily plus aspirin 81-100mg daily from day 46 to 6 months post-procedure, as supported by the most recent guidelines 1. The goal of this regimen is to prevent device-related thrombus formation while endothelialization occurs.
- The initial 45-day period with warfarin and aspirin is crucial for preventing early thromboembolic complications.
- The subsequent 6-month period with DAPT aims to reduce the risk of device-related thrombosis while the device becomes fully incorporated into the heart tissue.
- After 6 months, patients usually continue with aspirin 81-100mg daily indefinitely, as the risk of thromboembolic complications decreases significantly after this period. For patients with contraindications to warfarin, an alternative approach uses DAPT from the beginning, as suggested by observational studies 1. The specific regimen may be adjusted based on individual bleeding risk, with some centers using direct oral anticoagulants (DOACs) instead of warfarin for the initial period, although this approach is not universally recommended. Follow-up imaging with transesophageal echocardiography is typically performed at 45 days and 6 months to assess for device-related thrombus and adequate left atrial appendage closure before transitioning between medication phases, as mandated by regulatory approvals and real-world practice 1. Adherence to the prescribed anticoagulation regimen is crucial for preventing thromboembolic complications while the device becomes fully incorporated into the heart tissue, highlighting the importance of careful patient selection and monitoring.
From the Research
Anticoagulation Regimens after Watchman Device Placement
The recommended anticoagulation regimen after Watchman device placement varies depending on the patient's risk factors and medical history.
- Warfarin and aspirin are typically given for 45 days after implantation, followed by aspirin and clopidogrel for six months, and then aspirin indefinitely 2.
- For patients with an absolute contraindication to oral anticoagulation, antithrombotic therapy with aspirin and clopidogrel for six months, followed by daily aspirin indefinitely, may be feasible 2.
- Direct oral anticoagulants (DOACs) may also be used as an alternative to warfarin, with limited evidence suggesting they are not inferior following implantation of the device 2, 3.
Treatment of Device-Related Thrombus
Device-related thrombus is a major concern after Watchman device placement, and there is no consensus on the optimal method of treatment.
- A case report suggests that apixaban may be effective in treating device-related thrombus, with complete resolution of the thrombus after a short course of treatment 4.
- Further randomized controlled trials are needed to determine the choice and duration of drug therapy for device-related thrombus 4.
Outcomes and Safety
Studies have shown that the Watchman device is efficacious and safe in preventing stroke and systemic embolization, with low rates of bleeding and thromboembolic events 3, 5.
- A retrospective study found that patients implanted with a Watchman device had a low rate of adverse events, with only one post-procedure adverse event reported 5.
- A network meta-analysis found that both NOACs and the Watchman device were superior to warfarin in hemorrhagic stroke prevention, with NOACs also reducing total stroke and major bleeding compared to warfarin 6.