Patients with acute coronary syndrome (ACS) who undergo percutaneous coronary intervention (PCI) are at a higher risk of ischemic complications, even while receiving proper dual antiplatelet therapy. For this reason, identifying high-risk patients and personalizing treatment according to their profile could be a solution towards improving the efficacy and safety of the antiplatelet treatment.

This is a prospective single centre study analyzing correlations and clinical outcomes of patients in relation to biomarkers in acute coronary syndrome. The blood samples were collected from patients admitted to the hospital with a diagnosis of ACS and treated with dual antiplatelet therapy.

The blood samples were collected from each patient within the first 24 hours after the admission for acute coronary syndrome (ACS) and after 72 hours of hospitalization.

In this prospective, single-center, observational study, adult patients meeting the inclusion/exclusion criteria were included. Subjects enrolled at the Invasive Cardiology Unit of the 1st Department of Cardiology; Medical University of Warsaw (Poland) were cathegorized into three arms: 1) treated with aspirin and clopidogrel, 2) treated with aspirin and ticagrelor; 3) treated with aspirin and prasugrel. In all three groups subjects first obtained the loading dose of the drug and thereafter they received a fixed daily dose.

Blood samples were collected form each patient at two time-points: during the first 24 hours from hospital admission and after 72 hours following hospital admission. The parameters measured included selected platelet-derived microRNAs prticles, immature platelet fraction (IPF) and platelet microvesicles' comncentration. Platelet reactivity was established using Multiplate® Analyzer (Roche).

Inclusion Criteria:

1. Ability to provide written informed consent in a time window 1-24 hours after successful PCI;
2. Male or female, age ≥ 18 years at screening;
3. ACS at the time of the index hospitalization;
4. ACS patients undergoing PCI (New-Generation DES)
5. Use of a loading dose of P2Y12 inhibitor administered after diagnosis of ACS or after PCI;

Exclusion Criteria:

1. Unstable clinical status (hemodynamic or electrical instability);
2. Planned surgery requiring DAPT discontinuation during the study;
3. Coronary Revascularization (Surgical or Intervention) Program within 90 days
4. Prior stroke, transient ischemic attack or intracranial bleeding;
5. Active bleeding;
6. Severe anemia (hemoglobin < 8g/dL);
7. Platelet count ≤70x10^3/ml;
8. Hematocrit of < 30% or > 52%
9. Renal failure (hemodialysis or creatinine clearance ≤ 30 ml/min calculated with Cockroft-Gault formula);
10. Severe hepatic dysfunction (baseline alanine aminotransferase ≥ 2.5 times the upper limit of normal);
11. Known hypersensitivity or contraindication to ASA, clopidogrel, ticagrelor or prasugrel;
12. Under judicial protection, tutorship or curatorship;
13. Pregnancy;
14. Unable to understand and follow study-related instructions;
15. Enrollment in another investigational device or drug study.
16. Unable to provide an informed consent.

Adult population diagnosed with ACS on admission and treated primarily with PCI.