What is the current anticoagulation regimen post WATCHMAN (Left Atrial Appendage Closure) procedure?

Current Anticoagulation Regimen Post-WATCHMAN Device Implantation

The standard anticoagulation regimen post-WATCHMAN implantation consists of warfarin for 45 days, followed by dual antiplatelet therapy (DAPT) with aspirin and clopidogrel for 6 months, and then aspirin indefinitely. 1

Standard Protocol Based on Clinical Trials

The anticoagulation regimen following WATCHMAN left atrial appendage closure (LAAC) device implantation follows a specific timeline:

1. First 45 days post-implantation:

   • Warfarin therapy (target INR 2.0-3.0) 1
   • Often combined with aspirin (81-100mg daily)

2. Day 45 assessment:

   • Transesophageal echocardiography (TEE) to check for:
     • Device position
     • Peri-device leak (should be ≤5mm)
     • Device-related thrombus

3. If TEE shows adequate LAA closure at 45 days:

   • Discontinue warfarin
   • Start dual antiplatelet therapy (DAPT):
     • Aspirin (81-325mg daily)
     • Clopidogrel (75mg daily) 1, 2

4. 6 months post-implantation:

   • Discontinue clopidogrel
   • Continue aspirin indefinitely 1, 3

Alternative Anticoagulation Strategies

For Patients with Contraindications to Warfarin

• Direct Oral Anticoagulants (DOACs): Limited evidence suggests DOACs may be a non-inferior alternative to warfarin during the initial 45-day period 3, 2

• Dual Antiplatelet Therapy Only: For patients with absolute contraindications to oral anticoagulation:

  • DAPT with aspirin and clopidogrel may be used from implantation 4, 5
  • Higher risk of device-related thrombus (3.1% vs 1.4% with OAC) 4
  • Similar rates of major bleeding and thromboembolic events compared to OAC regimen 4

Important Considerations and Monitoring

Device-Related Thrombosis Risk

• Device-related thrombosis occurs more frequently with antiplatelet-only regimens (3.1%) compared to oral anticoagulation (1.4%) 4
• Careful monitoring with TEE is essential at 45 days and 12 months post-procedure 2

Bleeding Risk Assessment

• The initial 45-day period on warfarin represents a high-risk period for bleeding 1
• Shortened periods of anticoagulants and antiplatelets may be considered for patients with very high bleeding risk 6
• Treatment of hypertension in these patients is crucial as it reduces both intracranial hemorrhage and ischemic stroke risk 1

Patient Selection

• The FDA approval specifies that patients should be deemed suitable for short-term anticoagulation 1
• CMS has specified that patients should have a CHADS₂ score ≥2 or a CHA₂DS₂-VASc score ≥3 to be considered for the device 1

Special Circumstances

Device-Related Thrombus Management

If device-related thrombus is detected:

• Low molecular weight heparin (LMWH) or oral anticoagulants are recommended for treatment 2
• Follow-up TEE should be performed to confirm resolution

Patients with Recent Coronary Stenting

For patients with recent coronary stenting requiring WATCHMAN implantation:

• Bare metal stents are generally preferred over drug-eluting stents for AF patients taking warfarin 1
• A lower target INR of 2.0-2.5 may be recommended when triple therapy (warfarin, aspirin, clopidogrel) is necessary 1

The post-WATCHMAN anticoagulation regimen must balance stroke prevention with bleeding risk, with TEE monitoring at key timepoints to ensure proper device function and absence of thrombosis.