What is the recommended anticoagulation regimen for patients undergoing Percutaneous Coronary Intervention (PCI)?

Anticoagulation Regimen for Percutaneous Coronary Intervention (PCI)

Unfractionated heparin (UFH) is the recommended standard anticoagulant for patients undergoing PCI, with a weight-adjusted intravenous bolus of 70-100 IU/kg (or 50-70 IU/kg if used with a glycoprotein IIb/IIIa inhibitor). 1

Anticoagulation Options During PCI

Unfractionated Heparin (UFH)

• Dosing:
  • Without GP IIb/IIIa inhibitors: 70-100 IU/kg IV bolus to achieve ACT of 250-300s (HemoTec) or 300-350s (Hemochron) 1
  • With GP IIb/IIIa inhibitors: 50-70 IU/kg IV bolus to achieve ACT of 200-250s 1
• Evidence strength: Class I, Level A recommendation 1
• Advantages: Extensive experience, reversibility with protamine, low cost

Bivalirudin

• Dosing: 0.75 mg/kg IV bolus, followed by 1.75 mg/kg/h infusion during procedure 2
• Evidence strength: Class IIb, Level A recommendation 1
• Special considerations:
  • Preferred in patients with heparin-induced thrombocytopenia (Class I, Level C) 1
  • May reduce bleeding compared to UFH + GP IIb/IIIa inhibitors 1
  • Associated with slightly increased risk of acute stent thrombosis in primary PCI 3
  • Anticoagulant effect subsides approximately one hour after discontinuation 2

Enoxaparin

• Dosing:
  • If not previously treated: 0.5-0.75 mg/kg IV bolus 1
  • If previously treated with subcutaneous enoxaparin within 8 hours: no additional dose needed 1, 4
  • If last subcutaneous dose was 8-12 hours earlier: 0.3 mg/kg IV 1, 4
• Evidence strength: Class IIa, Level B recommendation 1

Fondaparinux

• Important caution: Should NOT be used as the sole anticoagulant for PCI due to risk of catheter thrombosis (Class III: Harm) 1
• If patient received fondaparinux before PCI, add UFH bolus (85 IU/kg, or 60 IU/kg with GP IIb/IIIa inhibitors) during procedure 1

Procedural Considerations

1. Access site selection:

   • Radial access preferred when possible to reduce bleeding complications 3

2. Monitoring anticoagulation:

   • ACT monitoring traditionally used but has uncertain utility in modern practice 1
   • Target ACT values:
     • 250-300s (HemoTec) or 300-350s (Hemochron) without GP IIb/IIIa inhibitors
     • 200-250s with GP IIb/IIIa inhibitors

3. GP IIb/IIIa inhibitors:

   • Should be considered only for bail-out in case of no-reflow or thrombotic complications 1
   • Not recommended as routine therapy when coronary anatomy is unknown 1

Post-PCI Anticoagulation

Anticoagulation should be discontinued immediately after PCI unless there is a compelling reason to continue 1, 4

• Full-dose anticoagulation is not recommended after successful uncomplicated PCI 4
• Parenteral anticoagulants should be discontinued after the procedure 1
• Continuing anticoagulation unnecessarily increases bleeding risk without additional benefit 4

Special Scenarios

Atrial Fibrillation Patients Requiring PCI

• For patients requiring long-term oral anticoagulation (e.g., atrial fibrillation):
  • A non-vitamin K antagonist oral anticoagulant (NOAC) is preferred over vitamin K antagonists 1, 5
  • Double therapy (OAC plus P2Y12 inhibitor) is recommended after hospital discharge for most patients 1, 5
  • Triple therapy (adding aspirin) should be limited to selected high thrombotic/low bleeding risk patients and for a short duration (≤1 month) 1, 5

Patients with Renal Impairment

• For bivalirudin: No reduction in bolus dose, but reduce infusion rate to 1 mg/kg/h if CrCl <30 mL/min 2
• For enoxaparin: Consider dose reduction and monitoring anti-Xa levels in severe renal impairment

Common Pitfalls to Avoid

1. Crossover between anticoagulants:

   • Avoid crossover between UFH and LMWH (Class III recommendation) 1
   • Never administer UFH to patients already receiving therapeutic enoxaparin ("stacking") 4

2. Prolonged anticoagulation:

   • Continuing parenteral anticoagulation after uncomplicated PCI increases bleeding risk without benefit 4

3. Fondaparinux as sole agent:

   • Never use fondaparinux as the sole anticoagulant during PCI due to risk of catheter thrombosis 1

4. Excessive heparin dosing:

   • Higher bleeding risk with excessive UFH doses, especially when combined with GP IIb/IIIa inhibitors 3
   • Recent evidence suggests no strong association between specific heparin dose or ACT levels and outcomes in patients treated with potent P2Y12 inhibitors without GP IIb/IIIa inhibitors 6

In conclusion, UFH remains the standard anticoagulant for PCI with established dosing protocols, while bivalirudin and enoxaparin are reasonable alternatives in specific clinical scenarios. Anticoagulation should be discontinued immediately after uncomplicated PCI to minimize bleeding risk.