Cerebrovascular Disease USMLE Step 1 Practice Question
A 74-year-old woman with a history of paroxysmal atrial fibrillation (not on anticoagulation) presents to the emergency department 7 hours after acute onset of right-sided facial droop, arm weakness, and mild aphasia. Vital signs are BP 158/92 mmHg, HR 118 and irregularly irregular, RR 16, temperature 37.2°C, SpO2 98% on room air. Non-contrast head CT shows no intracranial hemorrhage. MRI with DWI imaging demonstrates acute ischemic changes in the left middle cerebral artery territory with signal abnormality extending to the left M1 segment on MRA. The patient's family reports she is a poor historian regarding exact symptom onset time but witnessed symptom development while she was awake this morning. Which of the following is the most appropriate next step in management?
Answer choices
- AInitiate aspirin 325 mg daily without further intervention given late presentation
- BAdminister intravenous alteplase immediately without additional imaging
- CArrange urgent neurosurgical consultation for decompressive craniectomy
- DPerform CT angiography to assess for large vessel occlusion and consider mechanical thrombectomyCorrect answer
- EStart intravenous heparin followed by warfarin after 24 hours for atrial fibrillation
- FObserve with repeat neuroimaging in 24 hours and initiate antiplatelet therapy alone
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