Medical call center have no phone advice protocol within out of hospital cardiac arrest in France. The purpose of the present study is to compare a group of patients with protocol phone advice delivered by the dispatchers ("CONTARM" group) versus usual phone advice ( "CONTHAB" group). Comparison will be performed on survival to seven days. The hypothesis is that CONTARM group has an higher survival at seven days. A second goal is to measure the survival to 15 and 30 days. The trial is randomized, controlled and will include 2600 patients. The patients will be enrolled in 19 hospitals in France.