Association of seizure quality markers with postictal autonomic tone—the postictal heart rate correlates with seizure duration in electroconvulsive therapy

Hemodynamic changes constitute a component of the autonomic nervous system arousal in response to seizures induced by electroconvulsive therapy. Fluctuations in heart rate and blood pressure are the result of changes in the tone of the autonomic nervous system. This study investigates how changes in heart rate and blood pressure rate are related to electroconvulsive therapy quality parameters. The heart rate and blood pressure values from 29 patients across 112 sessions were retrospectively assessed and associated with electroconvulsive therapy seizure parameters. Electroconvulsive therapy seizure parameters, i.e., the stimulation charge, duration of the electroencephalography seizure, postictal suppression index, average seizure energy index, maximum sustained coherence, and mid-ictal amplitude, were used in linear mixed-effects models. The duration of the seizure predicted the postictal increase in heart rate, independently on the applied stimulus charge, parameters of seizure properties or interhemispheric synchronicity and postictal central inhibition capacity. Systolic and diastolic blood pressures showed only a non‑significant trend toward an increase after the electroconvulsive therapy seizure. Efforts to prolong the seizure duration while optimizing electroconvulsive therapy quality parameters may be associated with an elevated heart rate and may confer an additional burden for patients with cardiac disease.