Carotid sinus hypersensitivity: a cause of syncope in patients with tumors of the head and neck.

Carotid sinus hypersensitivity secondary to the presence of an underlying head and neck cancer has only recently been discussed in the literature. We present seven cases of carotid sinus hypersensitivity, each with paroxysmal bradycardia and hypotension associated both with and without palpation of the carotid bifucation. A discussion of the anatomy and the etiology of the hypersensitivity is given. Currently available therapeutic modalities are discussed in regard to their efficacy in this study. Carotid sinus hypersensitivity secondary to tumor in the neck is most often vasodilatory in nature and hence does not respond well to transvenous pacemaker. The best treatment for severe hypersensitivity appears to be periarteriectomy or intracranial nerve root section. Radiation therapy is occasionally beneficial.