STAT ECG Diagnoses: ruling out rapidly fatal diagnoses first, before diagnosing non life threatening conditions

HPI: A 31-year-old man with no past medical history presents to the ED at 4 am with chest pain for the past 3 hours. His pain is sharp, constant, 10/10 in intensity, pleuritic, and improved with leaning forward. He denies any recent URI or constitutional symptoms. He is groaning and looks uncomfortable. The following ECG is obtained:

Case ECG