Vasodepressor carotid sinus syncope associated with a neck mass.

Area of Science:

• Cardiology and Autonomic Neuroscience
• Neurology and Neoplastic Disease

Background:

• Recurrent vasodepressor syncope can be debilitating, with its etiology sometimes linked to specific anatomical or pathological conditions.
• Malignant cervical adenopathy, particularly involving the carotid sinus, presents a rare but significant potential cause of autonomic dysfunction.

Observation:

• A patient with left-sided malignant cervical adenopathy experienced recurrent episodes of extreme hypotension (vasodepressor syncope) lasting 10-30 minutes.
• These episodes were triggered spontaneously and by head-turning, occurring without significant heart rate changes, suggesting a specific reflex pathway.
• Baseline autonomic function tests (respiratory sinus arrhythmia, Valsalva maneuver, cold pressor test) were normal, indicating intact baroreceptor function between syncopal events.

Findings:

• The syncope episodes resolved with bedrest but recurred upon mobilization, indicating a dynamic physiological response.
• Intracranial section of the left glossopharyngeal nerve and upper vagal rootlets completely abolished the syncopal episodes.
• Postoperative autonomic testing remained normal, confirming the targeted nature of the intervention and the specific involvement of the affected nerves in the syncope.

Implications:

• This case suggests that left-sided carotid sinus involvement by malignant cervical adenopathy can precipitate purely vasodepressor syncope.
• The findings support the role of the glossopharyngeal and vagal nerves in mediating syncope triggered by carotid sinus stimulation in this context.
• Surgical intervention targeting specific cranial nerves may be an effective treatment for refractory vasodepressor syncope associated with carotid sinus pathology.