Cerebral bigeminy: alternating periodic epileptiform discharges

The EEG of a patient in coma after an anoxic event showed brief episodes in which two distinct epileptiform discharges of different amplitudes alternated with each other at regular intervals of approximately 1 sec. We have used the term 'cerebral bigeminy' to describe this pattern because its electrographic appearance is similar to cardiac bigeminy. The pattern was present for only part of the entire tracing and was not seen on earlier or later EEGs. This finding suggests that under appropriate circumstances periodic EEG events can occur as a result of reciprocal excitation of spike generators.