A 52-year-old woman with no prior migraine history presents with sudden-onset severe frontal headache, neck stiffness, and left-sided weakness. Vital signs: BP 156/92 mmHg, HR 98/min, RR 16/min, temp 37.2°C, SpO2 98% on room air. MR angiography demonstrates right carotid artery dissection with 80% stenosis and intimal flap. Serum glucose is 105 mg/dL. Which mechanism best explains ischemic stroke development in carotid dissection?

  1. A)Increased intracranial pressure from venous outflow obstruction
  2. B)Arterial rupture causing hemorrhagic transformation
  3. C)Thromboembolism from the dissected vessel and/or flow-limiting stenosisGABARITO
  4. D)Transient hypoxia from global hypoperfusion
  5. E)Acute vasospasm of the carotid artery

Explicação

Carotid artery dissection causes stroke through two mechanisms: (1) thromboembolism from the intimal flap and intramural hematoma, and (2) hemodynamically significant stenosis reducing distal perfusion. Both can occur simultaneously in significant dissections. Ver explicação completa e trilha adaptativa →

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