Carotid Space Mass Proximal to Vagus Nerve Causing Asystole and Syncope.

Manipulation of vagal nerve rootlets, whether surgical or through mass effect of a neoplasm, can result in asystole and hypotension, accompanied by ST depression and right bundle branch block. There are few case reports of a neoplasm causing these effects, and this case describes a patient with such a mass presenting with syncopal episodes. A 43-year-old man with a past medical history of HIV, bipolar disorder, and epilepsy was admitted to the neurology service for a video electroencephalogram (vEEG) to characterize syncopal episodes that were felt to be epileptic in origin. During the study, he experienced symptoms of his typical aura, which correlated with a transient symptomatic high degree AV block on telemetry, and an absence of epileptic findings on vEEG. Magnetic Resonance Imaging (MRI) of the brain showed a mass in the left posterior carotid space at the skull base. The patient underwent permanent dual chamber MRI-compatible pacemaker placement for his heart block. His syncopal episodes resolved, but presyncopal symptoms persisted. We discuss the presentation and treatment of vagal neoplasms.