PICSO in Patients With STEMI Treated by Primary Percutaneous Coronary Intervention

Inclusion Criteria: * First time anterior STEMI defined by the following: * Symptoms of myocardial ischemia \> 30 minutes and \< 12 hours * ST-segment elevation \> 1mm (\> 0.1 mV) in two contiguous precordial leads in the anterior territory on a 12-lead ECG * Uncomplicated PCI of a LAD culprit lesion (defined as angioplasty followed by stent placement or direct stenting without the occurrence of an adverse event(s) that would preclude further study participation, such as major bleeding, perforation, hypotension, pulmonary edema or instability that in the judgement of the investigator preclude participation in the trial) Exclusion Criteria: * Younger than 18 years of age * Hospitalization with a primary diagnosis of acute myocardial infarction (AMI) previously or has evidence of previous Q-wave infarct * Left main coronary artery culprit lesion * Additional stenosis in the LAD for which PCI or CABG is likely to be needed in the next 6 months and which is not treated during the index procedure * Cardiogenic shock (systolic blood pressure ≤90 mmHg in spite of conservative measures) or pulmonary edema (O2 saturation \<90% by pulse oximetry and the presence of rales or crackles) * Cardiac arrest requiring chest compression or resuscitation * Anatomical complications limit capacity to place PICSO Impulse device or achieve stable catheter placement or occlude coronary sinus * Known renal disease (GFR \< 30 mL/min/1.73m2) or dialysis * History of stroke, TIA or reversible ischemic neurological disease within last 6 months * Left bundle branch block * Known contra-indication for magnetic resonance imaging (Metallic implant precluding MRI, claustrophobia, obesity precluding MRI, etc.) * Presence of any lead in the coronary sinus * Active or treated malignancies in the last 12 months * Previous coronary artery bypass graft surgery * Known severe anemia (Hgb \< 10 g/dL or \< 6.2 mmol/L) * Known platelet count \< 100,000, known coagulopathy or bleeding diathesis, or unwilling to accept transfusions * Participation in another ongoing clinical study * Women of child-bearing age * Non-cardiac comorbidities and life expectancy \< 1 year * Legal incompetence * A condition that, in the opinion of the Investigator, precludes participation, including compliance with all follow-up procedures * No dependents neither to the sponsor nor to the investigator