Late heartbeat-evoked potentials are associated with survival after cardiac arrest

RATIONALE: Cardiac arrest (CA) is a serious condition
characterized by high mortality rates, even after initial successful
resuscitation, mainly due to neurological damage. Whether brain-heart
communication is associated with outcome after CA is unknown. Heartbeat-evoked
brain potentials (HEPs) represent neurophysiological indicators of
brain-heart communication. The aim of this study was to address the
association between HEPs and survival after CA.
METHODS: HEPs were calculated from resting EEG/ECG in 55 CA patients 24
hours after resuscitation. All patients were treated with targeted
temperature management and a standardized sedation protocol during
assessment. We investigated the association between HEP amplitude (180-
320 ms, 455-595 ms, 860-1000 ms) and 6-month survival.
RESULTS: Twenty-five of 55 patients (45%) were still alive at 6-month
follow-up. Survivors showed a higher HEP amplitude at frontopolar and
frontal electrodes in the late HEP interval than non-survivors. This
effect remained significant after controlling for between-group
differences in terms of age, Fentanyl dose, and time lag between
resuscitation and EEG assessment. There were no group differences in
heart rate or heart rate variability.
CONCLUSION: Brain-heart communication, as reflected by HEPs, is
associated with survival after CA. Future studies should address the
brain-heart axis in CA.