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[Activated clotting time post therapeutic anticoagulation with unfractionated heparin in patients undergoing elective
Jingyi Li1, Zhenyu Liu1, Shuyang Zhang2
1Department of Cardiology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100005, China.
Insights
Guideline-recommended unfractionated heparin (UFH) doses rarely achieve target activated clotting time (ACT) levels during percutaneous coronary intervention (PCI). ACT monitoring is crucial for optimizing UFH efficacy and safety in PCI procedures.
Area of Science:
- Cardiology
- Pharmacology
- Interventional Cardiology
Background:
- Percutaneous coronary intervention (PCI) commonly utilizes unfractionated heparin (UFH) for anticoagulation.
- Activated clotting time (ACT) monitoring is recommended by guidelines to ensure adequate anticoagulation during PCI.
Purpose of the Study:
- To evaluate the activated clotting time (ACT) levels achieved with guideline-recommended doses of unfractionated heparin (UFH) in patients undergoing PCI.
- To reinforce the importance of ACT monitoring for safe and effective anticoagulation during PCI.
Main Methods:
- A retrospective analysis of 1,062 patients undergoing elective PCI who received weight-adjusted UFH.
- Patients were categorized into three groups based on ACT levels: <300 s, 300-350 s, and >350 s.
- Factors influencing UFH anticoagulation and ACT levels were analyzed.
Main Results:
- Only 17.2% of patients achieved the target ACT range of 300-350 s after receiving weight-adjusted UFH.
- UFH dose per weight was correlated with ACT, while other patient factors were not significantly related.
- No major bleeding events occurred; minor bleeding and ischemic complication rates were similar across ACT groups, even with additional UFH in some low-ACT patients.
Conclusions:
- A small fraction of patients reach the target ACT with standard weight-adjusted UFH dosing in PCI.
- These findings underscore the necessity of continuous ACT monitoring to guide UFH therapy and ensure patient safety during PCI.
Objective:
To investigate the activated clotting time (ACT) level after administration of guideline-recommended dose of unfractionated heparin (UFH) and to confirm the importance of ACT monitoring in percutaneous coronary intervention (PCI).
Methods:
We performed a retrospective study on 1 062 patients undergoing elective PCI in Peking Union Medical College Hospital from May 1, 2011 to December 31, 2012. All patients were administrated weight-adjusted UFH (70-100 U/kg) based on PCI guideline of ACCF/AHA/SCAI. Patients were divided into 3 groups: ACT < 300 s (598 cases), ACT 300-350 s (183 cases) and ACT > 350 s (281 cases). ACT level and factors that may affect UFH anticoagulation were analyzed.
Results:
(1) The mean age was (63.0 ± 10.6) years and 751 (70.7%) patients were men. The mean weight was (70.5 ± 11.7) kg, and the mean UFH dose used was (100.7 ± 9.1) U/kg. (2) The median ACT was 285 (240-352) s after the UFH use. Pre-defined ACT target (300-350 s) was achieved only in 17.2% (183/1 062) patients. (3) Age, gender, height, weight, UFH/weight and the risk factors of coronary heart disease were similar among 3 groups (all P > 0.05). Multifactor linear correlation analysis showed that UFH/weight was related to ACT level (r = 0.07, P < 0.01), but other factors were not related to ACT level (all P > 0.05). (4) Among 598 patients with ACT < 300 s, 444 (74.2%) patients received additional UFH. No major bleeding events were observed in 1 062 patients. The incidence of minor bleeding and ischemic complications within 48 h after procedure were similar among 4 groups of ACT < 300 s with additional UFH, ACT < 300 s without additional UFH, ACT 300-350 s and ACT > 350 s (all P > 0.05).
Conclusions:
In this single-center study, only a small proportion of patients reached the ACT target after administration of weight-adjusted UFH. Our results supported the recommendation of ACT monitoring in current PCI guideline to improve efficacy and safety of UFH anticoagulation therapy.
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