Heparin Use During Coronary Angiography and PCI is Safe and Recommended
Unfractionated heparin (UFH) is the standard anticoagulant for all PCI procedures and should be administered routinely during your patient's coronary angiography and revascularization, regardless of diabetes, hypertension, recent cataract surgery, or planned DAPT with aspirin and ticagrelor. 1
Standard Heparin Dosing Protocol
Weight-adjusted UFH dosing is superior to fixed dosing and should be used: 1
- Without GP IIb/IIIa inhibitor: 100 IU/kg IV bolus, targeting ACT 250-350 seconds 1
- With GP IIb/IIIa inhibitor: 50-60 IU/kg IV bolus, targeting ACT 200-250 seconds 1
The European Society of Cardiology gives UFH a Class I, Level C recommendation for all PCI procedures, meaning it is universally recommended despite limited randomized trial data (because withholding anticoagulation during PCI would be unethical). 1
Post-Procedure Management: Do NOT Continue Heparin
Heparin must be discontinued immediately after uncomplicated PCI—continuing it increases bleeding risk without improving outcomes. 1, 2
- Post-procedural heparin infusions are explicitly not recommended, particularly when combined with DAPT or GP IIb/IIIa inhibitors 1, 2
- Continued heparinization after PCI is associated with more frequent bleeding events 1, 2
Exceptions requiring continued anticoagulation (use subcutaneous UFH, not IV): 1, 2
- Visible residual thrombus after the procedure
- Significant residual dissections not adequately treated
Interaction With Planned DAPT (Aspirin + Ticagrelor)
The FDA label explicitly warns that combining heparin with antiplatelet agents increases bleeding risk and recommends dose reduction when used together. 3 However, this combination is standard practice during PCI and the benefits outweigh risks when properly dosed:
- During procedure: Use the lower heparin dose (50-60 IU/kg) if GP IIb/IIIa inhibitors are added 1
- After procedure: Start or continue aspirin 75-100 mg daily plus ticagrelor 90 mg twice daily immediately 1
- The 2019 ESC guidelines give Class I, Level A recommendation for this DAPT regimen in ACS patients undergoing PCI 1
Recent Cataract Surgery Considerations
Recent cataract surgery is not a contraindication to heparin use during PCI. The bleeding risk from systemic anticoagulation affecting the eye is negligible compared to the thrombotic risk of performing PCI without anticoagulation. 1
- Cataract surgery wounds are typically sealed within 24-48 hours
- Systemic heparin during a 1-2 hour procedure poses minimal ocular bleeding risk
- The mortality benefit of successful revascularization far outweighs theoretical ocular complications
Critical Pitfall to Avoid: Never Switch Anticoagulants
If your patient received enoxaparin or another anticoagulant before the procedure, do NOT add UFH to achieve a target ACT. 4, 2
- Switching between anticoagulants (enoxaparin to UFH or vice versa) dramatically increases bleeding risk 4, 2
- This is a Class III recommendation (causes harm) from the European Heart Journal 4
- If the patient received subcutaneous enoxaparin within 8 hours, no additional anticoagulation is needed 1
- If enoxaparin was given 8-12 hours prior, give only 0.3 mg/kg IV enoxaparin (not UFH) 1
Diabetes and Hypertension: No Dose Adjustment Needed
Neither diabetes nor hypertension requires modification of standard UFH dosing during PCI. 1 These conditions increase baseline cardiovascular risk but do not alter heparin pharmacokinetics or bleeding risk sufficiently to warrant dose changes.
The TICO trial specifically demonstrated that ticagrelor-based DAPT in diabetic patients after PCI is safe and effective, with no increase in ischemic events. 5 Your planned DAPT regimen is appropriate for this diabetic patient.