EEG IN SYNCOPE

Syncope can be classified into four major categories: neruocardiogenic, neurologic , impaired cardiac output (due to structural abnormalities of the heart or due to dysrhythmias) and orthostatic hypotension. The term "temporal lobe syncope" is a term coined by Landolt. The patient has drop attacks and the EEG characteristically shows temporal lobe epileptic abnormalities. (JacomeDE, Clin Electroencephalogr, 1989 Jan 20:1, 58-65 ) Seizures always have to be considered in the differential diagnosis of syncope since the management is so drastically different. Epileptiform activity in the EEG done on syncope patients has a sensitivity of 0.40 and a specificity of 0.95 for the diagnosis of a seizure .( Hoefnagels WA, et al, J Neurol Neurosurg Psychiatry 1991 Nov 54:11, 953-6) Epileptiform activity on EEG nearly doubled the probability of a seizure in doubtful cases. Ictal bradycardia syndrome is a rare entity where epileptic discharges profoundly disrupt normal cardiac rhythm resulting in cardiogenic syncope during the event. This is to be considered in patients with refractory or unusual cases of syncope with features of both seizures and syncope.These patients may need both pacemaker placement and antiepileptic medications (Reeves, et al, Epilepsia 1996 Oct, 37:10, 983-7)

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