Late-Window Middle Cerebral Artery Occlusion With Transfer Constraint
67-year-old man with hypertension and atrial fibrillation not on anticoagulation is found by family at 23:10 after being last seen normal 8 hours earlier. On arrival, NIHSS is 12 with right hemiparesis, global aphasia, and left gaze deviation. Noncontrast CT ASPECTS is 8; CTA shows left M1 occlusion; CT perfusion shows core 25 mL and penumbra 95 mL (mismatch ratio 3.8). Blood pressure is 178/96 mmHg; glucose 132 mg/dL; INR 1.1; platelets 210,000/µL. He takes amlodipine and metoprolol and has no recent surgery or bleeding. His family reports no seizure at onset and no recent trauma. The local hospital can start intravenous thrombolysis but has no nighttime neurointervention; transfer to a comprehensive center takes 45 minutes by ambulance.
1. What reperfusion strategy should be pursued, and why is intravenous thrombolysis not automatically indicated here?
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This is a late-window (6–24 hour) anterior circulation large-vessel occlusion. The CTP profile - M1 occlusion, core 25 mL, penumbra 95 mL, mismatch ratio 3.8, NIHSS 12 - fits the imaging selection used for late-window endovascular thrombectomy. The correct priority is urgent transfer for thrombectomy, not local thrombolysis followed by observation.
IV alteplase is not indicated simply because he arrives within 24 hours. Standard IV thrombolysis is within 4.5 hours of last known well, or in selected wake-up strokes with MRI DWI-FLAIR mismatch. At 8 hours, without that MRI selection, IV thrombolysis would expose him to hemorrhage risk without established benefit. Do not delay transfer to give a non-indicated thrombolytic. If transfer were impossible, the decision would differ, but here thrombectomy capability exists 45 minutes away.
2. How should blood pressure be managed before and after reperfusion?
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Before transfer, avoid both hypotension and excessive hypertension. Because he is an EVT candidate, keep BP below 185/110 mmHg while not lowering it aggressively; a target around 160–180/90–100 is reasonable en route. Do not use sublingual nifedipine or rapid drops that could worsen penumbral perfusion.
After successful reperfusion, maintain BP below 180/105 mmHg for at least 24 hours and avoid intensive lowering to below 140 mmHg, which has been associated with worse outcomes in some trials. If reperfusion fails or is incomplete, permissive hypertension up to about 220/120 mmHg is acceptable unless there is another compelling indication. Treat fever, hypovolemia, and hypoxemia concurrently.
3. When and how should antithrombotic therapy and anticoagulation for atrial fibrillation be started?
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He did not receive thrombolysis, but he is going to have a large-territory infarct and possibly post-procedural hemorrhage risk. Start aspirin 160–300 mg within 24–48 hours after repeat imaging excludes hemorrhagic transformation. Do not start therapeutic anticoagulation in the first 24 hours.
For atrial fibrillation, a direct oral anticoagulant is appropriate for secondary prevention, but timing is individualized by infarct size and hemorrhagic transformation. In this moderate core (25 mL), starting around 4–7 days is reasonable after repeat imaging; with large infarcts or hemorrhagic transformation, delay to 14 days or longer. Bridge with aspirin until anticoagulation begins. The choice of DOAC should account for renal function, drug interactions, and cost; warfarin is an alternative if DOACs are unavailable.