Review Question - QID 214386

A 68-year-old man presents to the emergency department with slurred speech and right-sided weakness that started 30 minutes ago. The patient reports that he was eating breakfast with his wife when he dropped his spoon from his right hand and fell towards his right side. His wife noted a facial droop on the right side. He denied any head injury at the time. He currently reports resolution of his symptoms and denied having them ever in the past. He has a history of hypertension, hyperlipidemia, and migraine with aura. He smokes 1 pack of cigarettes daily for the past 40 years. On neurological examination, his face is symmetric with full strength and normal sensation in his bilateral upper and lower extremities. A diffusion-weighted MRI brain does not demonstrate an acute infarction. MR angiography of the head and neck is remarkable for 72% left-sided carotid stenosis. Which of the following is the most appropriate next step in management?