Changes in cardiac autonomic nervous system activity during a course of electroconvulsive therapy

Abstract

Aim Although electroencephalogram (EEG) seizure duration and seizure threshold change during a course of electroconvulsive therapy, the mechanisms by which these factors influence heart rate during subsequent electroconvulsive therapy sessions are currently unclear. In the current study, we investigated changes in heart rate during electroconvulsive therapy. Methods We recorded electroencephalography and electrocardiography during electroconvulsive therapy in 12 patients with major depressive disorder. Baseline heart rate was defined as the mean heart rate in the 30 seconds prior to stimulus onset. The TimeMax peak refers to the maximum heart rate after stimulus onset. Time1/2 points represent the time points at which the heart rate had decreased to a value midway between the baseline heart rate and the TimeMax peak. We examined the relationships between EEG seizure duration, TimeMax, and Time1/2 throughout the course of electroconvulsive therapy. Results Time1/2 decreased as the number of electroconvulsive sessions increased. Time1/2 was positively correlated with EEG seizure duration. Conclusion The duration in which electroconvulsive therapy‐induced sympathetic nervous system activation returned halfway to baseline levels gradually shortened during the course of electroconvulsive therapy.

Epinephrine levels decrease in responders after electroconvulsive therapy

“…Regardless of clinical outcome, levels of cortisol in serum and norepinephrine in plasma were significantly elevated at T2 compared to T1 and seemed to normalize in the course of ECT. It has previously been described that ECT has an effect on the autonomic nervous system and thus on norepinephrine release (Suzuki et al 2019). Based on the diencephalon hypothesis ECT-induced seizures must be sufficiently generalized in order to engage the diencephalic centers, which are associated with the regulation and modulation of physiological homeostasis, hormone release, appetitive behaviors, and diurnal rhythms.…”

“…Based on the diencephalon hypothesis ECT‐induced seizures must be sufficiently generalized in order to engage the diencephalic centers, which are associated with the regulation and modulation of physiological homeostasis, hormone release, appetitive behaviors, and diurnal rhythms. Furthermore, it is known that the diencephalon controls a variety of biological functions often implicated in depression through its hypothalamic releasing factors, involving the pituitary gland and autonomic nervous system (Suzuki et al 2019 ). In a study from 1989 with a different ECT technique (bidirectional square waveform), an increase of cortisol, epinephrine and norepinephrine was shown in the first two minutes after the seizure (Mann et al 1990 ).…”