Cerebrovascular Disease USMLE Step 1 Practice Question
A 45-year-old woman on oral contraceptives presents with acute onset occipital headache, right homonymous hemianopsia, and mild left-sided weakness. Vital signs show BP 138/82, HR 94, RR 16, temperature 37.2°C, and SpO2 98% on room air. MRI brain reveals acute infarction in the left posterior cerebral artery distribution. Cardiac examination is unremarkable without murmurs. Which of the following is the most likely underlying mechanism?
Answer choices
- AAtherosclerotic disease of the posterior cerebral artery
- BArterial dissection of the basilar artery
- CVasculitis from systemic lupus erythematosus
- DHypercoagulability from oral contraceptive use with thrombosisCorrect answer
- ECardioembolism from atrial fibrillation
- FParadoxical embolism through patent foramen ovale
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