Cerebrovascular Disease USMLE Step 1 Practice Question
A 72-year-old woman with atrial fibrillation not on anticoagulation presents with acute left-sided hemiparesis and facial droop. Vital signs show BP 158/92 mmHg, HR 98 and irregularly irregular, RR 16, temperature 37.2°C, and SpO2 98% on room air. MRI demonstrates acute infarction in the right middle cerebral artery territory. No hemorrhage is noted on imaging. Which of the following is the most likely mechanism of stroke in this patient?
Answer choices
- AAtherosclerotic disease of the right internal carotid artery
- BVasospasm from subarachnoid hemorrhage
- CHypercoagulable state from malignancy
- DSmall vessel disease with lacunar infarction
- ECardioembolism from atrial thrombusCorrect answer
- FParadoxical embolism through patent foramen ovale
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