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Is platelet function testing at the acute phase under P2Y12 inhibitors helpful in predicting bleeding in real-life
Claire Bal Dit Sollier1, Natacha Berge1, Sara Hamadouche2
1Thrombosis and Atherosclerosis Research Unit, Vessels and Blood Institute (IVS), Anticoagulation Clinic (CREATIF), Lariboisière Hospital, AP-HP, 75010 Paris, France.
Insights
Platelet function tests, including the vasodilator-stimulated phosphoprotein (VASP) index, did not predict bleeding risk in acute coronary syndrome (ACS) patients treated with newer P2Y12 inhibitors. These findings suggest current tests are not useful for guiding treatment decisions to prevent bleeding events.
Area of Science:
- Cardiology
- Pharmacology
- Clinical Medicine
Background:
- Current guidelines recommend potent P2Y12 inhibitors for acute coronary syndrome (ACS) despite increased bleeding risk compared to clopidogrel.
- Assessing bleeding risk is crucial for optimizing ACS patient management.
Purpose of the Study:
- To evaluate the predictive value of platelet function testing for bleeding events in ACS patients receiving newer P2Y12 inhibitors.
- To determine if VASP index or aggregation tests can identify patients at higher risk of bleeding.
Main Methods:
- Retrospective analysis of 364 ACS patients treated with ticagrelor, prasugrel, or clopidogrel.
- Platelet function was assessed using VASP index and aggregation tests during initial hospitalization.
- Bleeding events were recorded using the Bleeding Academic Research Consortium (BARC) classification during follow-up.
Main Results:
- Lower VASP index and platelet inhibition were observed with newer P2Y12 inhibitors (ticagrelor, prasugrel) compared to clopidogrel.
- Overall bleeding rates (BARC 2-5) were similar across all P2Y12 inhibitor groups (7.7%).
- Neither VASP index nor aggregation test results could establish a threshold for predicting increased bleeding risk.
Conclusions:
- Platelet function tests (VASP index, aggregation) performed during the acute phase of ACS are not effective in predicting subsequent bleeding risk.
- The utility of platelet function testing later in the treatment course for predicting bleeding requires further investigation.
Background:
In patients with acute coronary syndrome (ACS), current international guidelines recommend newer potent and predictable P2Y12 inhibitors as first-line treatment despite a greater bleeding risk compared with clopidogrel.
Aim:
To determine if platelet function testing can predict bleeding in real-life patients with ACS treated with newer P2Y12 inhibitors.
Methods:
In this retrospective study, all consecutive adults admitted to the Lariboisière University Hospital for ACS, whatever the P2Y12 inhibitor prescribed, who had platelet function testing (vasodilator-stimulated phosphoprotein phosphorylation [VASP] index and aggregation tests) during the initial hospital stay were included. Follow-up was performed to record bleeding events according to the Bleeding Academic Research Consortium (BARC) classification.
Results:
A total of 364 patients were included, treated with ticagrelor (n=123), prasugrel (n=105) or clopidogrel (n=136); 42.3% after an ST-segment elevation myocardial infarction, 27.1% after a non-ST-segment elevation myocardial infarction and 30.6% with unstable angina. Mean age was 64±11 years. Median VASP index was significantly lower with the newer P2Y12 inhibitors (14% under ticagrelor, 14% under prasugrel) than with clopidogrel (42%). Despite these differences in the degree of platelet inhibition, the occurrence of bleeding (BARC 2-5) during follow-up was 7.7% overall, and was similar for all P2Y12 inhibitors (ticagrelor 8.9%; prasugrel 6.6%; clopidogrel 7.4%). For each P2Y12 inhibitor, it was impossible to determine a VASP index threshold under which bleeding was significantly greater during follow-up. Similarly, ADP-induced aggregation was more profoundly inhibited by ticagrelor and prasugrel than by clopidogrel, but this did not allow a threshold to be set for increased haemorrhagic risk.
Conclusions:
Despite the substantial occurrence of bleeding in patients with ACS during follow-up, neither the VASP index nor platelet aggregation test results measured at the acute phase were helpful in predicting bleeding risk. Whether platelet function testing could be helpful later in the course of treatment remains to be evaluated.
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