Reducing Micro Vascular Dysfunction in Acute Myocardial Infarction by Ticagrelor

Inclusion Criteria: 1. Provision of informed consent 2. Patients presenting with ST-elevation myocardial infarction \<12 hours after symptom onset 3. Successful percutaneous coronary intervention of the infarct-related vessel with a modern drug-eluting stent 4. Intermediate stenosis in non-infarct-related vessel (50-90%) Exclusion Criteria: 1. history of myocardial infarction 2. Participation in another clinical study with an investigational product during the preceding 30 days 3. history of cerebrovascular accident (CVA) or 'transient ischaemic attack' (TIA) 4. History of intracranial haemorrhage 5. indication or use of oral anticoagulant therapy (i.e. acenocoumarol) 6. severe liver dysfunction (Child-Pugh score 10-15) 7. congestive heart failure 8. cardiogenic shock 9. left ventricular ejection fraction \< 35% 10. bleeding diathesis 11. age ≥ 75 or \< 18 12. body weight \< 60 kg 13. gout 14. coagulation disorders 15. severe pulmonary disease 16. pregnancy and breast feeding 17. limited life expectancy 18. platelet count \< 100 000/mm3 19. history of drug addiction or alcohol abuse in the past 2 years 20. need for chronic nonsteroidal anti-inflammatory drug 21. creatinine clearance \<30 mL/min or dialysis 22. chronic total occlusion (CTO) 23. Left main disease 24. allergy or contra-indication for ticagrelor or prasugrel 25. Contra-indication for adenosine 26. Patients unable to be followed on-site 27. Unable to undergo or contra-indications for MRI 28. Contra-indication for drug-eluting stent 29. Inability to obtain informed consent 30. Coronary artery bypass grafting in medical history