What is the recommended anticoagulation regimen, including dosing and frequency, for a patient with a ventricular thrombus?

Anticoagulation Order for Ventricular Thrombus

For a patient with left ventricular thrombus, initiate warfarin with a target INR of 2.5 (range 2.0-3.0) for 3 months, with bridging using unfractionated heparin or low molecular weight heparin until therapeutic INR is achieved for at least 24 hours.

Initial Bridging Anticoagulation

Start immediately upon diagnosis:

• Unfractionated heparin (UFH): IV bolus followed by continuous infusion targeting aPTT 1.5-2.0 times control 1

  • Alternative: Enoxaparin 1 mg/kg subcutaneous every 12 hours 1
  • Alternative: Enoxaparin 40 mg subcutaneous once daily 1

• Continue parenteral anticoagulation for minimum 5 days AND until INR ≥2.0 for at least 24 hours 1

Warfarin Dosing

Initiate on same day as parenteral therapy:

• Start warfarin on day 1 of heparin therapy 1
• Adjust dose to achieve target INR 2.5 (range 2.0-3.0) 1
• For patients with anterior MI and high-risk features (EF <40%, anteroapical wall motion abnormality), the target INR is 2.5-3.5 1

Concomitant Antiplatelet Therapy

If patient has NOT undergone stenting:

• Add aspirin 75-100 mg daily to warfarin for first 3 months 1
• After 3 months, discontinue warfarin and continue dual antiplatelet therapy per ACS guidelines 1

If patient underwent bare-metal stent (BMS):

• Triple therapy (warfarin INR 2.0-3.0 + aspirin + clopidogrel 75 mg daily) for 1 month 1
• Warfarin + single antiplatelet for months 2-3 1
• Then discontinue warfarin and continue dual antiplatelet therapy 1

If patient underwent drug-eluting stent (DES):

• Triple therapy (warfarin INR 2.0-3.0 + aspirin + clopidogrel 75 mg daily) for 3-6 months 1
• Then discontinue warfarin and continue dual antiplatelet therapy 1

Duration of Anticoagulation

• Standard duration: 3-6 months for LV thrombus 1
• Continue until thrombus resolution is documented by repeat imaging 1
• If thrombus persists beyond 3 months, consider extending therapy 1

Alternative: Direct Oral Anticoagulants (DOACs)

While guidelines prioritize warfarin, emerging evidence supports DOACs as alternatives 2, 3:

Apixaban: 10 mg twice daily for 7 days, then 5 mg twice daily 2

• Recent RCT showed non-inferiority to warfarin with 94% thrombus resolution rate 2
• No major bleeding events in apixaban group vs 2 in warfarin group 2

Rivaroxaban: 15 mg twice daily for 21 days, then 20 mg once daily 4, 3, 5

Note: DOACs are NOT currently guideline-recommended as first-line therapy but may be considered in patients unable to maintain therapeutic INR or with contraindications to warfarin 4, 2, 3

Critical Monitoring Points

• INR monitoring: Check INR every 2-3 days initially until stable, then weekly, then monthly 1
• Time in therapeutic range (TTR): Maintain TTR ≥50% to minimize embolic risk 6
  • Patients with TTR <50% had 19% embolic event rate vs 2.9% with TTR ≥50% 6
• Repeat imaging: Perform echocardiography at 3 months to assess thrombus resolution 1, 2

Common Pitfalls to Avoid

• Inadequate bridging: Do not stop heparin until INR therapeutic for 24 hours 1
• Subtherapeutic anticoagulation: Most strokes on warfarin occur with subtherapeutic INR 4, 6
• Premature discontinuation: Complete minimum 3-month course even if early imaging shows resolution 1
• Excessive bleeding risk with triple therapy: Use lowest effective aspirin dose (75-100 mg) and limit triple therapy duration 1