A 58-year-old male presents to the emergency department with complaints of chest pain that started suddenly while he was gardening. He describes the pain as a squeezing sensation in the center of his chest, radiating to his left arm. He has a history of hypertension and hyperlipidemia. On physical examination, his vital signs are stable, and his ECG is ordered to evaluate his cardiac function. The ECG shows depression of the ST segment and T wave inversion in multiple leads. Based on the ECG findings and the patient's symptoms, what is the most likely diagnosis?
A. Ventricular tachycardia
B. Atrial fibrillation
C. First-degree atrioventricular (AV) block
D. Atrial flutter
E. Acute myocardial infarction (MI)