Activated Clotting Time–Guided Anticoagulation During Percutaneous Coronary Intervention
Unfractionated heparin (UFH) during PCI is titrated to an activated clotting time (ACT) target range using point-of-care ACT monitoring. [1] A protocol using standardized ACT targets based on the ACT device and planned antiplatelet regimen is recommended in catheterization laboratory best-practice guidance. [2]
Heparin Dosing Protocol (UFH)
When UFH has not been previously administered, an initial UFH bolus of 70 to 100 units/kg IV is recommended to achieve a target ACT of 250 to 300 seconds. [1] If ACT is not in the therapeutic range during PCI after UFH administration, additional UFH is recommended (example additional UFH 2000 to 5000 units) to achieve an ACT of 250 to 300 seconds. [1]
Target ACT Ranges
UFH target ACT ranges are device dependent. [1] For HemoTec or I-Stat ACT devices, the target ACT is 250 to 300 seconds for UFH dosing. [1] For Hemochron ACT devices, an ACT goal is 50 seconds higher than the HemoTec or I-Stat goal (target range 300 to 350 seconds). [1] When IV glycoprotein IIb/IIIa inhibitors are planned, a target ACT of 200 to 250 seconds is recommended. [1]
ACT Monitoring Strategy
ACT should be checked throughout the procedure for patients receiving heparin to monitor adequate anticoagulation. [2] ACT values should be recorded in the procedural documentation. [2]
Alternative Anticoagulants
Bivalirudin
Bivalirudin dosing during PCI is a 0.75 mg/kg IV bolus followed immediately by a 1.75 mg/kg/h IV infusion for the duration of the procedure. [1] Five minutes after the bolus dose, ACT should be assessed to determine whether an additional bolus of 0.3 mg/kg is needed. [3] A single ACT measurement is considered acceptable for patients receiving bivalirudin as procedural monitoring. [2]
Enoxaparin
For patients treated previously with subcutaneous enoxaparin in whom the last SC dose was administered 8 to 12 hours earlier or only 1 SC dose has been administered, an IV enoxaparin dose of 0.3 mg/kg at the time of PCI is recommended. [1] For patients whose last SC enoxaparin dose was administered within the previous 8 hours, no additional enoxaparin should be given at the time of PCI. [1] For patients who have not received prior anticoagulant therapy, UFH is the parenteral anticoagulant for ACT-based dosing in the referenced PCI dosing table. [1]
Argatroban
For argatroban during PCI, dosing is 200 micrograms/kg IV bolus followed by 15 micrograms/kg/min IV infusion. [1] An alternative argatroban dosing option listed for PCI is 350 micrograms/kg bolus followed by 15 micrograms/kg/min infusion. [1]
Important Clarifications
Higher target ACT should be considered in the setting of chronic total occlusion (CTO) or acute coronary syndrome (ACS). [1] When ACT device selection is Hemochron, ACT targets are shifted upward by 50 seconds relative to HemoTec/I-Stat targets. [1]
Treatment Initiation Thresholds and Dose Adjustment Triggers
UFH should be titrated to achieve the ACT target range specified for the ACT device and adjunct antiplatelet strategy. [1] Dose adjustment with additional UFH should occur when ACT is not in the therapeutic range. [1] For bivalirudin, an additional 0.3 mg/kg bolus is triggered by ACT assessment at 5 minutes after the initial bolus. [3]
Common Pitfalls to Avoid
Failure to perform ACT checks during heparin-based anticoagulation increases the risk of inadequate anticoagulation due to lack of intraprocedural monitoring. [2] Using the wrong ACT device–specific target range results in ACT goals that are not aligned with the dosing table. [1]
Target Blood Pressure
No blood pressure targets apply specifically to ACT-guided anticoagulation during PCI in the cited anticoagulation protocols. [1]
Key Evidence and Guideline Basis for ACT-Guided Dosing
The referenced PCI anticoagulant dosing table provides specific UFH bolus dosing, ACT targets by device, and ACT adjustment guidance during PCI. [1] SCAI catheterization laboratory best-practice guidance specifies ACT monitoring through the procedure and provides ACT targets based on antiplatelet regimen status. [2] Bivalirudin prescribing information provides the procedural ACT assessment timing and criteria for an additional bivalirudin bolus. [3]