How long do you treat a pulmonary embolism (PE) with heparin (unfractionated heparin) infusion before switching to Eliquis (apixaban)?

Duration of Heparin Treatment Before Switching to Eliquis for Pulmonary Embolism

For patients with pulmonary embolism (PE), heparin infusion should be administered for at least 24-48 hours before transitioning to Eliquis (apixaban), with overlap not required due to apixaban's rapid onset of action. 1, 2

Anticoagulation Protocol for PE

Initial Heparin Therapy

• Start with unfractionated heparin (UFH) as an IV bolus of 80 units/kg 2
• Follow with continuous infusion at approximately 18 units/kg/hr
• Adjust dose to maintain aPTT at 1.5-2.3 times control (46-70 seconds) 2
• Continue heparin for 24-48 hours until ready to transition to Eliquis 1

Transition to Eliquis (Apixaban)

• Begin Eliquis at 10 mg twice daily for 7 days 2
• After 7 days, reduce to 5 mg twice daily for continued treatment 2
• Unlike with vitamin K antagonists, there is no need for 5+ days of overlap between heparin and Eliquis 1

Advantages of This Approach

The European Society of Cardiology guidelines support this approach, noting that only a "1-2 day administration of UFH" is needed before transitioning to Eliquis 1. This is because:

1. Apixaban has a rapid onset of action (reaching peak plasma levels within 3-4 hours)
2. Apixaban has a predictable anticoagulant effect
3. The initial 7-day higher dosing of apixaban (10mg BID) provides immediate therapeutic anticoagulation 1, 2

Special Considerations

• Renal function: UFH is preferred over Eliquis in patients with severe renal impairment (CrCl <30 mL/min) 1
• Hemodynamic instability: Patients with hemodynamic compromise may require longer heparin therapy if thrombolysis is being considered 2
• Bleeding risk: Assess bleeding risk before transitioning; high-risk patients may require careful monitoring during transition

Duration of Total Anticoagulation

After transitioning to Eliquis, the total duration of anticoagulation depends on the clinical scenario:

• PE secondary to transient/reversible risk factors: 3 months 1, 2
• Unprovoked PE: At least 3 months, with consideration for extended therapy 1, 2
• Recurrent PE: Indefinite anticoagulation 1, 2

Common Pitfalls to Avoid

1. Unnecessary prolonged heparin therapy: Unlike with warfarin, extended overlap is not required with Eliquis
2. Inadequate initial heparin dosing: Failure to achieve therapeutic aPTT (>1.5 times control) is associated with a 25% risk of recurrent thromboembolism 3
3. Incorrect Eliquis dosing: Remember the loading dose of 10mg twice daily for the first 7 days is essential for immediate therapeutic effect 2
4. Missing follow-up: Patients should be routinely re-evaluated 3-6 months after acute PE to assess for complications and need for extended therapy 1, 2