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Updated: Jun 26, 2026
Thrombus Profiling Assay: A Microfluidics-Based Platform for Comprehensively Characterizing Biomechanical Thrombogenesis
Published on: January 9, 2026
Thrombotic events in high risk patients are predicted by evaluating different pathways of platelet function
Anna Maria Gori1, Rossella Marcucci, Rita Paniccia
1Department of Medical and Surgical Critical Care, University of Florence, Florence, Italy. am.gori@dac.unifi.it
Insights
Assessing platelet reactivity with multiple methods, including adenosine 5'-diphosphate (ADP), arachidonic acid (AA), and collagen, better predicts thrombotic events in patients on dual antiplatelet therapy after stent implantation.
Area of Science:
- Cardiology
- Pharmacology
- Thrombosis Research
Background:
- Dual antiplatelet therapy (DAPT) is crucial after drug-eluting stent implantation.
- Assessing platelet function is important for predicting clinical events in patients on DAPT.
- Current methods for measuring platelet reactivity have limitations in identifying patients at risk.
Purpose of the Study:
- To evaluate the appropriate methodology for assessing platelet reactivity to identify patients at risk of thrombotic events.
- To compare different methods of measuring post-treatment residual platelet reactivity (RPR) after stent implantation.
Main Methods:
- A cohort of 746 patients with successful drug-eluting stent implantation were analyzed.
- Post-treatment residual platelet reactivity (RPR) was measured using platelet-rich plasma (adenosine 5 -diphosphate, arachidonic acid, collagen) and whole blood (PFA-100 system).
- Clinical events, including stent thrombosis and cardiac mortality, were assessed at six-month follow-up.
Main Results:
- RPR assessed by two or three stimuli (ADP, AA, collagen) was significantly associated with higher rates of primary (stent thrombosis) and secondary (cardiac mortality, stent thrombosis) endpoints.
- Specificity values for RPR identified by two or three stimuli were higher than for single stimuli or PFA-100.
- The positive likelihood ratio for RPR by three stimuli or by ADP and collagen was higher than for other methods, indicating better predictive value.
Conclusions:
- Evaluating platelet reactivity using multiple agonists (ADP, AA, collagen) is superior to single agonists or the PFA-100 system for identifying patients at risk of thrombotic events on DAPT.
- Methods exploring different platelet activation pathways are necessary for accurate risk assessment in patients undergoing stenting.
- This study supports a multi-modal approach to platelet function testing for optimizing antiplatelet therapy.
Abstract:
A higher rate of clinical events in poor clopidogrel and/or aspirin responders was documented by using different methods to measure platelet function, but no conclusive data about the appropriate methodology to explore platelet reactivity are available. A total of 746 patients included in the cohort of the RECLOSE trial who had successful drug-eluting stent implantation were assessed for post-treatment residual platelet reactivity (RPR) in platelet-rich plasma by 10 microM adenosine 5'-diphosphate (ADP), 1 mM arachidonic acid (AA) and 2 microg/ml collagen-induced platelet aggregation and in whole blood by the PFA-100 system. At six-month follow-up, RPR by two stimuli (ADP and AA or ADP and collagen) and by three stimuli (ADP, AA and collagen) is significantly associated with higher percentage of primary (definite or probable stent thrombosis) and secondary (cardiac mortality and stent thrombosis) end-points than RPR by ADP, AA, collagen and PFA-100 system. According to the primary and secondary end points, the specificity values for RPR identified by two (ADP and AA:94%; ADP and collagen:97%) and three stimuli were higher with respect to RPR by ADP (88%), or RPR by AA (83%) or RPR by collagen (90%). The positive likelihood ratio values of RPR by three stimuli (9.55) or of RPR by ADP and collagen (8.08) were higher than those of RPR by ADP (2.59), by AA (2.05), by collagen (4.73), or by PFA-100 (2.63). This prospective study documents that the evaluation of platelet reactivity addressed to identify patients at risk of thrombotic events on dual antiplatelet treatment has to be carried out by methods able to explore different pathways.
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