In 34 patients admitted in Neurological Intensive Care Unit, for a cerebral hematoma by ruptured arterio-venous malformation, are present in 26 patients, on the first day. In many cases, the APTT is increased and this can be respected. These disorders do not seem to modify the incidence of delayed hemorrhage, except for the severe perturbances, related to a DIC or an hepatic deficiency. In these cases, the delayed hemorrhage must be prevented by transfusions of platelets and/or freeze fresh plasma.