Partial epileptic seizures of different origin variably affect cardiac rhythm

The present study was aimed at evaluating electrocardiographic (ECG) changes associated with partial epileptic seizures without seizure activity secondarily generalized.

We assessed heart rate (HR) changes occurring during 100 partial epileptic seizures, as recorded by ambulatory EEG-ECG in 50 outpatients. Consecutive R-R intervals were measured for the 30 s immediately preceding the onset and for the first 10-s period of discharge. In addition, HR was sampled at 10-s intervals during EEG paroxysmal discharge and for 1 min after the end of discharge.

The highest and lowest respective HR peaks achieved during these seizures were 186 and 44 beats/ min. Analysis of the R-R intervals during the first 10-s period of EEG discharge showed a significant early HR increase in 49% of the seizures; the corresponding figure for an early HR reduction was 25.5%. Eighty percent of the seizures showing an early HR decrease were of temporal lobe origin. No severe cardiac arrhythmias were noted during the seizures.

Our data suggest that an early HR decrease is more probable in temporal lobe seizures than in seizures of other origin. An accurate HR measurement, focused on discharge onset, may provide both a reliable way of evaluating the possible effect of partial seizures on HR and valuable information about the cerebral sites involved in the control of cardiac rhythm.