A 60-year-old woman presents to the emergency department wit…

A 60-year-old woman presents to the emergency department with sudden onset of right-sided weakness and slurred speech. A non-contrast CT of the head rules out hemorrhage, and further imaging confirms a left middle cerebral artery infarct. Her past medical history includes hypertension, hyperlipidemia, and type 2 diabetes mellitus. She is a nonsmoker. What is the most likely underlying cause of this patient’s cerebrovascular accident (CVA)?