When to transition from heparin (unfractionated heparin) to Eliquis (apixaban) in a patient with new atrial fibrillation (AFib)?

Transitioning from Heparin to Apixaban in New Atrial Fibrillation

When transitioning from heparin infusion to apixaban in patients with new atrial fibrillation, apixaban should be started and heparin discontinued when the aPTT returns to within normal range, typically 4-6 hours after stopping the heparin infusion.

Transition Protocol

For Standard Transition (Most Patients)

1. Stop heparin infusion without a taper
2. Check aPTT 4-6 hours after heparin discontinuation
3. Administer first dose of apixaban when aPTT returns to normal range
   • Standard dose: 5 mg twice daily
   • Reduced dose (2.5 mg twice daily) if patient meets ≥2 of these criteria:
     • Age ≥80 years
     • Body weight ≤60 kg
     • Serum creatinine ≥1.5 mg/dL

For Urgent Transition (Hemodynamically Unstable Patients)

If the patient requires immediate cardioversion due to hemodynamic instability:

1. Perform cardioversion without waiting for prior anticoagulation 1
2. Start heparin immediately after cardioversion with:
   • Initial IV bolus followed by continuous infusion
   • Target aPTT 1.5-2 times control value 1
3. Transition to apixaban as per standard protocol above
4. Continue anticoagulation for at least 4 weeks after cardioversion 1

Special Considerations

Duration of Anticoagulation

• For AF lasting >48 hours or unknown duration:
  • Continue apixaban for at least 4 weeks after cardioversion 1
  • Long-term anticoagulation decisions should be based on CHA₂DS₂-VASc score 1

Dosing Adjustments

• Use standard dose (5 mg twice daily) unless specific dose reduction criteria are met
• Inappropriate dose reduction may lead to increased risk of thromboembolic events 2

Monitoring Requirements

• No routine coagulation monitoring is required with apixaban
• This differs from warfarin, which requires INR monitoring at least weekly during initiation and monthly when stable 1

Clinical Pearls and Pitfalls

Common Pitfalls

1. Overlapping anticoagulation: Administering apixaban while heparin is still active increases bleeding risk
2. Inappropriate dose reduction: Using reduced dose without meeting criteria increases stroke risk
3. Premature discontinuation: Stopping anticoagulation too early after cardioversion increases thromboembolic risk

Important Considerations

• Apixaban is preferred over warfarin in eligible patients due to lower bleeding risk and no need for routine monitoring 3
• For patients undergoing elective cardioversion, therapeutic anticoagulation with apixaban for at least 3 weeks before cardioversion is recommended 1
• For patients with AF of documented duration ≤48 hours, start anticoagulation at presentation and proceed with cardioversion rather than delaying for 3 weeks 1

By following this protocol, you can ensure a safe and effective transition from heparin to apixaban in patients with new atrial fibrillation, minimizing both bleeding and thromboembolic risks.