Study of Platelet Function After Administration of Aspirin Versus Lysine Acetylsalicylate in STEMI Patients

Effects of Intravenous Lysine Acetylsalicylate Versus Oral Aspirin on Platelet Responsiveness in Patients With ST-segment Elevation Myocardial Infarction: a Pharmacodynamic Study (ECCLIPSE-STEMI Trial)

Prasugrel and ticagrelor, new P2Y12-ADP receptor antagonists, are associated with greater pharmacodynamic inhibition and reduction of cardiovascular events in patients with an acute coronary syndrome. However, evidence is lacked about the effects of achieving faster and stronger cyclooxygenase inhibition with intravenous lysine acetylsalicylate (LA) compared to oral aspirin on prasugrel inhibited platelets. Recently, we demonstrated in healthy volunteers that the administration of intravenous LA resulted in a significantly reduction of platelet reactivity compared to oral aspirin on prasugrel inhibited platelets. Loading dose of LA achieves platelet inhibition faster, greater and with less variability than aspirin. However, there are no data of this issue in patients with an ST-segment elevation myocardial infarction (STEMI). The ECCLIPSE-STEMI trial will study the effect of LA versus aspirin in platelet reactivity in patients with STEMI

This is a prospective, randomized, single-center, open platelet function study conducted in 60 STEMI patients. Subjects were randomly assigned to receive a loading dose (LD) of intravenous LA 450mg plus oral prasugrel 60mg/ticagrelor 180mg, or LD of aspirin 300mg plus prasugrel 60mg/ticagrelor 180mg orally. Platelet function was evaluated at baseline, 30 min, 1h, 4h, and 24h using multiple electrode aggregometry and vasodilator-stimulated phosphoprotein phosphorylation (VASP). The primary endpoint of the study is the inhibition of platelet aggregation after arachidonic acid (AA) 1.5mM at 30 min. Secondary endopoints are the inhibition of platelet aggregation after AA baseline and at 1h, 4h and 24h, and measurement of aggregation with other platelet test (ADP, collagen and VASP).

Inclusion Criteria:

• Aged > 18.
• Patients with ST-segment myocardial infarction.
• Signed written informed consent.

Exclusion Criteria:

• Known allergies to aspirin, clopidogrel, prasugrel or ticagrelor.
• Cardiogenic shock or hemodinamic instability.
• Recent antiplatelet therapy (<14 days).
• Oral anticoagulation with a coumarin derivative.
• Any active bleeding or blood dyscrasia.
• Recent gastrointestinal bleeding (<6 months prior to inclusion).
• Recent history of stroke, TIA or intracranial bleeding (<6 months prior to inclusion).
• Known anemia, trombopenia or severe chronic kidney/liver disease
• Any known active neoplasm.
• Pregnant females.