Hemorrhagic Myocardial Infarction Detection by Post-reperfusion Troponin Kinetics

Inclusion Criteria: 1. Age ≥ 18 years 2. Index STEMI 3. Coronary angiogram with PCI to occur irrespective of the onset of the symptoms. 4. Ability to provide informed consent for themselves Exclusion Criteria: 1. History of prior myocardial infarction, 2. Cardiogenic shock, 3. Patients who present with current cardiac arrest 4. Any contraindication to cardiac CMR (claustrophobia, pacemaker or cardiac defibrillator, known allergy to gadolinium), 5. Presence of permanent atrial fibrillation, 6. Unconscious patient, 7. Severe renal insufficiency (creatinine clearance ≤ 30 ml/min/m2 or renal replacement therapy), 8. Women who are pregnant or breastfeeding. Women of reproductive potential must have a negative pregnancy test.