Syncope in Patient with Bilateral Severe Internal Carotid Arteries Stenosis/Near Occlusion: A Case Report and Literature Review.

Background: Syncope is commonly worked up for carotid stenosis, but only rarely attributed to it. Considering paucity of such cases in literature, we report a case and discuss the pathophysiology.

Design/methods: We report a patient with high-grade bilateral severe internal carotid artery (ICA) stenosis who presented with syncopal episodes in the absence of stroke, orthostatic hypotension, significant cardiovascular disease, or vasovagal etiology. We reviewed all literature pertaining to syncope secondary to carotid stenosis and other cerebrovascular disease.

Results: A 67-year-old man presented with two brief syncopal episodes. History and physical examination was not suggestive of seizure or vasovagal syncope. Other workup was negative for any stroke or syncope secondary to cardiac or vasovagal etiology. Magnetic resonance angiography (MRA) revealed bilateral ICA severe stenosis. This was confirmed by transfemoral carotid vessels angiography. Internal carotid angioplasty and stenting was performed on one side. After this, the patient remained asymptomatic. After one month, carotid endarterectomy (CEA) of contralateral side was performed. Patient remained symptom free after that. On review of literature, we identified only 12 cases of syncope attributable to carotid stenosis and reviewed 24 cases attributable to other cerebrovascular disease.

Conclusion: Syncope secondary to carotid stenosis, especially in the absence of any focal ischemic events is rare. It can only be expected in those patients who have bilateral hemodynamically significant carotid disease, which is unlikely in the absence of any focal ischemic events.