 Prospective observational multicenter study to evaluate copeptin as a prognostic marker in patients with an acute cerebrovascular event. It includes four groups of patients, mainly depending on type of initial therapy intra-arterial thrombolysis, intravenous thrombolysis, conservative treatment, TIA. The study takes place at the Emergency and neurological Department of the University of Bern, Switzerland; Department of Neurology, Goethe University of Frankfurt a.M. Germany. Further participating centers are under discussion 