The Effect of Opioids on P2Y12 Receptor Inhibition in Patients With ST-Elevation Myocardial Infarction Who Are Pre-treated With Crushed Ticagrelor

Inclusion Criteria: i. age ≥18 years ii. referred by ambulance paramedics to Isala (Zwolle) or Zuyderland Hospital (Heerlen) iii. diagnosed in the ambulance with STEMI defined as: 1. ongoing chest pain \>30 minutes and \<12 hours duration and 2. ST-segment elevation \>0.1 milliVolt in at least 2 contiguous leads iv. ongoing chest pain with a pain score (NRS) ≥4 v. the patient has been informed of the nature of the study, agrees to its provisions and has provided verbal informed consent in the pre-hospital phase followed by written informed consent in hospital Exclusion Criteria: i. presenting with cardiogenic shock; defined as: 1. systolic blood pressure \<90 mmHg and 2. heart rate \>100/min and 3. peripheral oxygen saturation \<90% (without oxygen administration) ii. patients with a nasogastric tube in situ or requiring a nasogastric tube iii. patients who already received fentanyl or paracetamol \<2 hours prior to randomization iv. patients on current treatment with P2Y12 inhibitors (ticagrelor, clopidogrel or prasugrel) v. allergy to morphine or paracetamol vi. patients with recent major bleeding complications or contraindication to dual antiplatelet therapy: 1. hypersensitivity to aspirin or ticagrelor 2. current use of (new) oral anticoagulation 3. history of bleeding diathesis or known coagulopathy 4. active bleeding 5. refusal of blood transfusions 6. history of intracerebral mass, aneurysm, arteriovenous malformation, or hemorrhagic stroke 7. known severe liver dysfunction vii. received any organ transplant or is on a waiting list for any organ transplant viii. patients undergoing dialysis ix. pregnant or lactating female x. patients currently participating in another investigational drug or device study