⁃ Subjects screened for either the Prospective Control Cohort or the SSO2 Treated (On-Label or All Others) Cohorts must meet ALL the following baseline criteria:

• Men or women aged 18 years or older

• Presentation with AMI and successful revascularization of the infarct-related artery with PCI

• The subject or their legally authorized representative has been informed of the nature of the study, agrees to its provisions and has been provided and signed written informed consent, approved by the appropriate Institutional Review Board (IRB)

⁃ Treatment with SSO2 Therapy will be up to the physician's discretion and the decision will be made prior to enrollment in the study. Any subject that is treated with SSO2 Therapy and meets the baseline criteria should be invited to participate in the study.

⁃ Subjects who are in the Prospective Control Cohort as well as subjects enrolled in the SSO2 Treated On-Label Cohort must meet these additional criteria:

• The primary culprit lesion must be in the left anterior descending (LAD) coronary tree

• Successful primary PCI within 6 hours of symptom onset, as documented by \<50% diameter residual angiographic stenosis and Thrombolysis in Myocardial Infarction (TIMI) Grades 2 or 3 flow in the target vessel

• No major complications such as perforation, serious bleeding, or cardiogenic shock

• Not pregnant or nursing