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Updated: May 16, 2026
Microfluidics in Assessing Platelet Function
Published on: November 8, 2024
Increased platelet aggregation and turnover in the acute phase of ST-elevation myocardial infarction
Kristian Løkke Funck-Jensen1, Jens Dalsgaard, Erik Lerkevang Grove
1Department of Cardiology, Aarhus University Hospital , Aarhus , Denmark.
Insights
Newly produced platelets in ST-elevation myocardial infarction (STEMI) reduce the effectiveness of aspirin and clopidogrel. Increased platelet turnover during the acute phase may explain this diminished antiplatelet effect.
Area of Science:
- Cardiology
- Hematology
- Pharmacology
Background:
- Platelet production increases during acute ST-elevation myocardial infarction (STEMI).
- This heightened platelet activity may impact the efficacy of standard antiplatelet therapies like aspirin and clopidogrel.
- Understanding platelet dynamics is crucial for optimizing treatment in STEMI patients.
Purpose of the Study:
- To investigate the antiplatelet effects of aspirin and clopidogrel in the acute phase of STEMI.
- To evaluate platelet turnover in STEMI patients during the acute phase versus a stable phase 3 months later.
- To determine if increased platelet turnover influences antiplatelet drug efficacy.
Main Methods:
- Observational follow-up study of 48 STEMI patients undergoing primary percutaneous coronary intervention (PPCI).
- Administration of loading doses of aspirin and clopidogrel prior to PPCI.
- Assessment of residual platelet aggregation using Multiplate® and VerifyNow® aggregometry.
- Evaluation of platelet turnover indices (MPV, IPF, IPC) via automated flow cytometry at multiple time points.
Main Results:
- Significantly higher residual platelet aggregation was observed in the acute STEMI phase before PPCI compared to later time points (4, 12 hours, and 3 months).
- Platelet turnover indices, including mean platelet volume, immature platelet fraction, and immature platelet count, were significantly elevated in the acute STEMI phase.
- These increases in platelet turnover markers were significantly reduced at the 3-month follow-up.
Conclusions:
- Dual antiplatelet therapy with aspirin and clopidogrel showed reduced efficacy in the acute phase of STEMI.
- Elevated platelet turnover in acute STEMI is a significant finding.
- Increased platelet turnover may be a key factor contributing to the diminished effectiveness of antiplatelet drugs during acute STEMI.
Abstract:
Newly produced platelets are present in the acute phase of ST-elevation myocardial infarction (STEMI). This may influence the antiplatelet effect of aspirin and clopidogrel administered prior to primary percutaneous coronary intervention (PPCI). The aims of this study were to investigate the antiplatelet effect of aspirin and clopidogrel and evaluate platelet turnover in the acute phase of STEMI compared to a stable phase 3 months later. In this observational follow-up study on 48 STEMI patients transferred for PPCI, loading doses of aspirin (300 mg) and clopidogrel (600 mg) were given orally in the ambulance. Blood samples were obtained immediately prior to PPCI, at 4 and 12 hours after administration of bolus doses and at follow-up after 3 months. Residual platelet aggregation was evaluated by Multiplate® and VerifyNow® aggregometry. Platelet turnover was evaluated by automated flow cytometry. In the acute phase of STEMI at the time of PPCI, residual platelet aggregation was significantly higher prior to PPCI compared to 4 and 12 hours after loading doses of aspirin and clopidogrel and 3 months later (p-values < 0.01). Furthermore, platelet turnover indices (mean platelet volume, immature platelet fraction, and immature platelet count) were increased in the acute phase of STEMI compared to 3 months after PPCI (p-values < 0.0001). In conclusion, residual platelet aggregation was high in the acute phase of STEMI despite dual antiplatelet treatment with aspirin and clopidogrel. Increased platelet turnover may partly explain the reduced efficacy of antiplatelet drugs in the acute phase of STEMI.
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