What is the recommended dose of Lovenox (enoxaparin) as an IV bolus for Primary Percutaneous Coronary Intervention (PPCI)?

Recommended Dose of Lovenox (Enoxaparin) as IV Bolus for Primary Percutaneous Coronary Intervention (PPCI)

The recommended dose of enoxaparin as an IV bolus for Primary Percutaneous Coronary Intervention (PPCI) is 0.5 mg/kg. 1

Evidence-Based Dosing Recommendations

• For patients who have not received prior anticoagulant therapy, the American College of Cardiology/American Heart Association (ACC/AHA) guidelines recommend an IV bolus of 0.5-0.75 mg/kg enoxaparin at the time of PCI 1
• The European Society of Cardiology (ESC) specifically recommends a 0.5 mg/kg IV bolus of enoxaparin for STEMI patients undergoing primary PCI 1
• Clinical studies have consistently used a regimen of 0.5-0.75 mg/kg IV enoxaparin for both elective PCI and PPCI 1, 2

Special Considerations for Prior Enoxaparin Administration

• If the patient has received subcutaneous enoxaparin within 8 hours before PPCI, no additional enoxaparin should be given 1
• If the patient has received subcutaneous enoxaparin 8-12 hours before PPCI or has only received one subcutaneous dose, an additional IV dose of 0.3 mg/kg should be administered 1
• For patients who received the last subcutaneous dose more than 12 hours before PPCI, full-dose de novo anticoagulation is recommended 1

Clinical Evidence Supporting Efficacy and Safety

• Studies have demonstrated that a 0.5 mg/kg IV bolus of enoxaparin achieves therapeutic anti-Xa levels (>0.5 IU/ml) in 97.5% of patients undergoing PCI 2
• The STEEPLE trial showed that a 0.5 mg/kg dose of enoxaparin was associated with significantly reduced bleeding compared to unfractionated heparin (5.9% vs 8.5%, p=0.01) while maintaining efficacy 3
• In STEMI patients, a prehospital IV bolus of 0.5 mg/kg followed by subcutaneous enoxaparin has been shown to provide adequate anticoagulation for PPCI with rare bleeding complications (major bleeding 1.4%) 4

Important Caveats and Considerations

• "Stacking" of anticoagulants (giving UFH to patients already on enoxaparin) should be avoided as it significantly increases bleeding risk 1
• Dose adjustment is necessary for patients with severe renal impairment (CrCl <30 mL/min) 5
• Monitoring anti-Xa levels is not routinely required due to the predictable anticoagulant effect of enoxaparin 1, 2
• Unlike unfractionated heparin, enoxaparin has a more predictable anticoagulant effect and does not require activated clotting time (ACT) monitoring during PPCI 1, 3

Comparison with Other Anticoagulants for PPCI

• Unfractionated heparin dosing for PPCI is 70-100 U/kg IV bolus (when no glycoprotein IIb/IIIa inhibitor is planned) or 50-70 U/kg IV bolus (when glycoprotein IIb/IIIa inhibitor is planned) 1
• Bivalirudin is administered as a 0.75 mg/kg IV bolus followed by a 1.75 mg/kg/h infusion during PPCI 1, 6
• Fondaparinux is not recommended as the sole anticoagulant for PPCI due to increased risk of catheter thrombosis 1

Algorithm for Enoxaparin Use in PPCI

1. For patients with no prior anticoagulation:

   • Administer 0.5 mg/kg IV bolus of enoxaparin 1

2. For patients with prior subcutaneous enoxaparin:

   • If last dose <8 hours ago: No additional enoxaparin 1
   • If last dose 8-12 hours ago or only 1 dose given: Add 0.3 mg/kg IV bolus 1
   • If last dose >12 hours ago: Full dose (0.5 mg/kg IV bolus) 1

3. For patients with severe renal impairment (CrCl <30 mL/min):

   • Consider dose reduction and monitor closely for bleeding 5