Ictal tachycardia in children with epilepsy

Changes in heart rate (HR) may provide an extracerebral indicator of seizure onset. The purpose of this study is to assess the frequency and timing of presentation of ictal tachycardia in a larger series of children with epilepsy grouped in different age groups as well as the influence of seizure characteristics.

We retrospectively reviewed 732 seizures of 195 patients aged 0 to 14 (median 6.91) years with epilepsy of any cause. Patients were grouped according to the age in groups (1) <1 year (n = 18); (2) 1-2 years (n = 26); (3) 2-6 years (n = 43); (4) 6-10 years (n = 44); and (5) 10-14 years (n = 64). HR was assessed visually during the seizures and compared with HR 1 min before seizure onset. The time from seizure onset to ictal tachycardia, defined as an increase in HR by at least 33 %, was described. Ictal tachycardia was considered early if occurring in the first 10 s.

Ictal tachycardia occurred in at least one seizure in 70.3 % of patients and in 51.1 % of seizures. It was more frequent and earlier in focal seizures and in seizures occurring in sleep. >30 % of patients had ictal tachycardia in all of their seizures, this being more frequent in the age groups 6-10 and 10-14 years.

Children older than 6 years especially with focal seizures during sleep could be ideal candidates for warning devices or stimulation therapies triggered by tachycardia detection. Future studies should aim to assess the implications in relation to the risk of SUDEP.