Severe Orthostatic Hypotension due to Unilateral Carotid Artery Dissection.

A 46-year-old woman was admitted to our hospital with mild right-sided hemiparesis and orthostatic hypotension. Magnetic resonance angiography of the neck showed stenosis of the left distal carotid sinus surrounded by intraluminal hyperintensities on both T1-weighted and T2-weighted images, representing a periluminal hematoma secondary to carotid artery dissection. The dissection hyper-extended the carotid artery wall and stimulated baroreceptors in the carotid sinus. The stimulated baroreceptors induced carotid sinus hypersensitivity, which may have been related to her orthostatic hypotension. Post-stroke orthostatic hypotension should prompt consideration of carotid artery dissection.