Parapharyngeal space lesions syncope-syndrome. A newly proposed reflexogenic cardiovascular syndrome

An intense vaso-vagal reaction characterizes those reflex cardiovascular syncopes in which the glossopharyngeal nerve constitutes the main afferent nerve pathway. In these syndromes, afferent fibres of the glossopharyngeal nerve project from the baroreceptorial area to the medullary cardiac and vasomotor centres, from which efferent fibres descend into the vagus. The most common reflex cardiovascular syndromes linked to the IX nerve are carotid sinus syndrome (CSS) and glossopharyngeal neuralgia-asystole syndrome (GNS). Eleven male patients (mean age 65.4 years) with recurrent and severe vaso-vagal attacks are described. The episodes were characterized by asthenia and general malaise, pallor, sudation, unrecordable or very low (40-60 mmHg) arterial blood pressure, mental disorientation and/or syncope. The admission diagnosis in these patients was CSS, but the clinical picture was quite different from classic CSS: triggering factors were not present, vasovagal episodes were longer, syncopes were more frequent and severe and VVI pacing was ineffective. Further investigation, including computerized tomography, showed in all patients a malignant or benign pathological growth occupying and compressing the parapharyngeal space. The authors think that the symptoms exhibited by their patients may be attributed to parapharyngeal space involvement. The pathogenetic mechanism of syncope in these cases could be similar to that occurring in GNS except for the absence of neuralgia itself. Surgical carotid sinus denervation or A-V sequential DDD pacing were ineffective in completely controlling symptoms. Intracranial section of the IX nerve appears to be the most effective mechanism for controlling the syndrome.(ABSTRACT TRUNCATED AT 250 WORDS)