Patients with acute ischaemic stroke and intravenous thrombolysis or patients with acute ischaemic stroke refusing intravenous thrombolysis, relatives (1st or 2nd degree) of patients with acute ischaemic stroke, patient with acute or subacute ischaemic stroke with a contraindication for intravenous thrombolysis and patients without acute ischaemic stroke (admitted to the Department of Cardiology (Charité, Campus Benjamin Franklin, Germany).