A 45-year-old man presents to the emergency department with a complaint of chest pain that started an hour ago. He describes the pain as a pressure-like sensation that radiates to his left arm. His past medical history is significant for hypertension and hyperlipidemia. On examination, his vital signs are: blood pressure 140/90 mmHg, heart rate 78 beats per minute, respiratory rate 18 breaths per minute, and oxygen saturation 98% on room air. An electrocardiogram (ECG) shows normal sinus rhythm without any ST-segment changes. Which of the following is the most appropriate next step in the management of this patient? (Select All that Apply.)