Contribution of Myocardial Perfusion Imaging in the Initial Assessment of Acute Coronary Syndromes Without ST Elevation for the Diagnosis of Myocardial Infarction or Differential Diagnoses

Inclusion Criteria: * Patient over 18 years of age * Hospitalised in cardiology as an emergency for acute coronary syndrome without ST segment elevation with indication for coronary angiography within 72 hours of admission * Not yet undergone coronary angiography. * Troponin \>99th percentile, i.e. \>27ng/l (troponin I, hypersensitive, Abbott) * With de novo segmental kinetic disorder on TTE or ECG repolarisation disorder outside ST elevation * Patient affiliated with a health insurance scheme * French-speaking patient * Patient who has given their free, informed and written consent Exclusion Criteria: Haemodynamically unstable patient: HR \> 100 and/or systolic blood pressure \< 90 mmHg and/or diastolic blood pressure \< 60 mmHg and/or oxygen saturation \< 92% in AA and/or clinical signs of hypoperfusion (mottling, cyanosis) * Rhythmically unstable patient: sustained ventricular tachycardia, sudden death recovered. * Patient with a known allergy to ultrasound contrast medium * Patient with ST segment elevation. * Patient with a contraindication to MRI. * Patient with a caricatured picture of myocarditis (fever and/or significant biological inflammatory syndrome with CRP\>50mg/l) * Patients already included in a type 1 interventional research protocol (RIPH1) * Patients under guardianship or curatorship * Patients deprived of their liberty * Patients under judicial protection * Pregnant or breastfeeding patients (negative pregnancy test for women of childbearing age)