99mTc-HMPAO Brain SPECT Imaging in a Case of Repeated Syncopal Episodes Associated With Smoking

Background We report here a rare case of repeated syncopal episodes associated with smoking and findings of 99mTc–hexamethylpropyleneamine oxime (HMPAO) brain single-photon emission CT (SPECT) imaging. Case Description A 77-year-old man had four syncopal episodes during a half-month period. All four occurred when he stood up and walked immediately after smoking a cigarette, and syncope did not occur after cessation of smoking. Although upright testing revealed orthostatic hypotension, the patient did not complain of fainting on standing alone. Compared with brain SPECT in the supine position, perfusion was decreased in the posterior circulation structures after the subject smoked a cigarette or chewed nicotine gum. Conclusions The combination of cerebral vasoconstriction due to smoking and orthostatic hypotension probably decreased cerebral blood flow in this patient, resulting in syncope.