Planned or anticipated treatment with endovascular reperfusion strategies (e.g. intra‐arterial thrombolysis, mechanical recanalisation techniques)
Pre‐stroke disability (inability to carry out all daily activities, requiring some help or supervision, i.e. slight disability corresponding to an mRS score > 1)
Participation in any investigational study in the previous 30 days
Severe stroke by clinical assessment (e.g. NIHSS > 25)
Hypersensitivity to alteplase or any of the excipients
Pregnancy or lactating (formal testing needed in woman of childbearing potential; childbearing potential is assumed in women up to 55 years of age)
Significant bleeding disorder at present or within past 6 months
Known haemorrhagic diathesis
Manifest or recent severe or dangerous bleeding
Known history of or suspected intracranial haemorrhage
Suspected subarachnoid haemorrhage (even if CT is negative) or condition after subarachnoid haemorrhage from aneurysm
History of central nervous system damage (e.g. neoplasm, aneurysm, intracranial or spinal surgery)
Recent (within 10 days) traumatic external heart massage, obstetrical delivery, recent puncture of a non‐compressible blood vessel
Current use of anticoagulants (e.g. phenprocoumon, warfarin, new anticoagulants such as dabigatran) or current use of heparin and elevated thromboplastin time (low‐dose subcutaneous heparin is allowed)
Platelet count < 100,000/mm3
Blood glucose < 50 or > 400 mg/dL (< 2.8 or 22.2 mmol/L)
Severe uncontrolled hypertension, i.e. systolic blood pressure > 185 mmHg or diastolic blood pressure > 110 mmHg or requiring aggressive medication to maintain blood pressure within these limits (routine medical treatment is allowed to lower the blood pressure below these limits)
Manifest or recent bacterial endocarditis, pericarditis
Manifest or recent acute pancreatitis
Documented ulcerative gastrointestinal disease during the last 3 months, oesophageal varices, arterial aneurysm, arterial/venous malformations
Neoplasm with increased bleeding risk
Manifest severe liver disease including hepatic failure, cirrhosis, portal hypertension, and active hepatitis
Major surgery or significant trauma in past 3 months
Stroke within 30 days
Life expectancy 6 months or less by judgement of the investigator
Any condition associated with a significantly increased risk of severe bleeding not mentioned above
Any contraindication to MRI (e.g. cardiac pacemaker)