Review Question - QID 108757

An 81-year-old woman presents to her primary care physician with a 6 month history of occasional weakness in her right arm and leg. She reports 3 such episodes that each lasted approximately 1 hour and did not leave any long-term symptoms. The patient denies numbness, tingling, pain, or changes in her speech. She has a medical history of hypertension and coronary artery disease with stable angina. Her medications include aspirin, lisinopril, amlodipine, and atorvastatin dose as moderate-intensity. She reports a 40-pack-year smoking history and occasional alcohol intake. Her temperature is 98.5°F (36.9°C), blood pressure is 142/87 mmHg, pulse is 70/min, and respirations are 14/min. She has a systolic ejection murmur best heard at the right upper sternal border and there is a carotid bruit on the left side. Her lungs are clear. Neurologic exam reveals intact cranial nerve function, 1+ deep tendon reflexes in bilateral patellae and biceps, as well as 5/5 strength and intact pinprick sensation in all extremities. Carotid ultrasound is performed and identifies 52% stenosis on the right side and 88% on the left. Which of the following is the most appropriate next step in management?