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Direct Oral Anticoagulants Affect Activated Clotting Time During and Bleeding Events After Percutaneous Coronary
Eiji Shibahashi1, Takuro Abe2, Kazuho Kamishima3
1Department of Cardiovascular Intervention, Tokyo Women's Medical University Adachi Medical Center, Tokyo, Japan.
Insights
Direct oral anticoagulants (DOACs) increase activated clotting time (ACT) during percutaneous coronary intervention (PCI) procedures. Patients on DOACs experienced higher bleeding rates post-PCI compared to those not on DOACs.
Area of Science:
- Cardiology
- Pharmacology
Background:
- High activated clotting time (ACT) during percutaneous coronary intervention (PCI) increases bleeding risk.
- The impact of direct oral anticoagulants (DOACs) on ACT kinetics and clinical outcomes during PCI is not well understood.
Purpose of the Study:
- To investigate the relationship between DOAC use, ACT levels, and adverse clinical events in patients undergoing PCI.
Main Methods:
- Observational study of 246 patients undergoing PCI.
- Patients were divided into DOAC users (n=31) and non-users (n=215).
- ACT measured before and 30 minutes after unfractionated heparin during PCI; bleeding and thromboembolic events tracked for 30 days.
Main Results:
- DOAC users had significantly higher ACT levels both before and after heparin administration compared to non-users (p < 0.001).
- Bleeding event rates were significantly higher in DOAC users (16.1%) versus non-users (4.7%) (p = 0.028).
- Systemic thromboembolism rates were low and similar between groups (0% vs 3.7%, p = 0.60).
Conclusions:
- DOAC use is associated with elevated ACT during PCI.
- Patients on DOACs experience a higher incidence of bleeding events following PCI.
- Further research is needed to optimize anticoagulation strategies in PCI patients using DOACs.
Abstract:
Inappropriately high activated clotting time (ACT) during percutaneous coronary intervention (PCI) is associated with an increased risk of bleeding events. However, whether the prescription of direct oral anticoagulants (DOACs) affects ACT kinetics during heparin use and adverse clinical events in patients who underwent PCI remains unclear. We aimed to evaluate the relations between ACT changes during and adverse clinical events after PCI in patients who were prescribed DOAC. This observational study included 246 patients who underwent PCI at the 2 cardiovascular centers who were not receiving warfarin and whose ACT was recorded immediately before and 30 minutes after injection of unfractionated heparin. Patients were divided into 2 groups according to DOAC prescription at the time of the index PCI: DOAC users (n = 31) and nonusers (n = 215). Any bleeding and systemic thromboembolic events were investigated until 30 days after PCI. The average age of this population was 70.5 years, and 66.3% were male. Average ACT was significantly higher in DOAC users than nonusers both before and 30 minutes after unfractionated heparin induction (157.2 ± 30.1 vs 131.8 ± 25.1 seconds, p <0.001; 371.1 ± 122.2 vs 308.3 ± 82.2 seconds, p <0.001; respectively). The incidence of systemic thromboembolism after PCI was low and comparable between the 2 groups (0% vs 3.7%, p = 0.60). However, the rate of any bleeding event was significantly higher in DOAC users than in nonusers (16.1% vs 4.7%, p = 0.028). Patients receiving DOAC have higher ACT during PCI and higher incidence of bleeding events than those not receiving DOAC.
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