Out-of-hospital and in-hospital cardiac arrest (CA) requiring intensive care unit management. Data collection using a standardized form : demographic data and data related to the CA according to the Utstein guidelines.. Circumstances of onset, dates and times of onset and control of abnormal movements (myoclonus and.or seizures). On-scene clinical findings, pre-hospital and hospital care providers, timing of various treatments and supportive care, results of etiological investigations, cause of CA. Dates and times of EEG monitoring, EEG results. Outcomes including vital status and Cerebral Performance Category scale score at ICU and hospital discharge, day-90 and 1-year after CA and determined based on data in the ICU and/or hospital/neurologist charts and/or general practitionner phone interview.