NCT03022552 - Heart Attack Research Program: Platelet Sub-Study (HARP)

Inclusion Criteria: - Acute ischemic symptoms compatible with diagnosis of MI, such as chest pain or anginal equivalent symptoms at rest or new onset exertional anginal equivalent symptoms - Objective evidence of MI (either or both of the following): - Elevation of troponin to above the laboratory upper limit of normal (ULN) - ST segment elevation of ≥1mm on 2 contiguous ECG leads - Willing to provide informed consent and comply with all aspects of the protocol - Administration of aspirin at least 1 hour before cardiac catheterization - Administration of thienopyridine (e.g., clopidogrel, ticagrelor) at least 1 hour before cardiac catheterization - Women and men with ≥50% of any major epicardial vessel on invasive angiography may participate Exclusion Criteria: - Recent use of vasospastic agents, such as cocaine, triptans, or ergot alkaloids (≤1 month) - Alternate explanation for troponin elevation, such as hypertensive urgency, acute exacerbation of heart failure, chronic elevation due to kidney disease, pulmonary embolism, cardiac trauma - Pregnancy - Thrombolytic therapy for STEMI (qualifying event) - Use of any of the following medications: - Platelet antagonists (except aspirin and thienopyridines) within 7 days - NSAIDs (e.g., ibuprofen, naproxen) within 3 days. - Thrombocytopenia (platelet count <100,000) - Thrombocytosis (platelet count >500,000) - Anemia (hemoglobin <9 mg/dl) - Hemorrhagic diathesis