A 62-year-old man presents to a regional emergency department with 45 minutes of central chest tightness radiating to the left arm and jaw, associated with diaphoresis. His blood pressure is 145/85 mmHg, heart rate 96 beats/min, oxygen saturation 98% on room air. A 12-lead ECG is being obtained and venous access has been established. He has not taken any medications prior to arrival and has no history of peptic ulcer disease or bleeding. What is the single most appropriate immediate pharmacological intervention?