Super Saturated Oxygen (SSO2) Therapy in Patients With ST-segment Elevation Myocardial Infarction (STEMI) and Action on Coronary Microcirculation Dysfunction

Ten patients with acute anterior STEMI undergoing primary PCI will be enrolled. After successful PCI of a proximal lesion or middle left anterior descending artery (LAD), the patient will be informed and emergency consent will be obtained. SSO2 therapy will then be performed. Blood is drawn from a femoral artery sheath and circulated via a roller pump through an extracorporeal oxygenator located in a polycarbonate chamber to achieve a PaO2 of 760 to 1000 mmHg. The overoxygenated blood is then delivered to the origin of the LAD at a flow rate of 100 ml/min for 60 minutes via a dedicated catheter. Improvement in CMD will be assessed by comparing angio-IMR before and after 60 minutes of SSO2 therapy measured on conventional angiographic images. Then, conventional follow-up of previous STEMI will be performed by imaging and functional assessment. The primary endpoint will be analyzed using a paired Student's t test, to take into account the evolution "before/after" implementation of SSO2 therapy on CMD. The demonstration of the beneficial effect of SSO2 therapy on CMD will allow the development of a care strategy based on CMD measurement by angio-IMR. Thus, this new treatment could be reserved for patients with severe CMD for which our management arsenal is still lacking, even though we know that CMD is a major prognostic factor in STEMI patients.