IntraCranial Atherosclerosis Related Large-vessel Occlusion Treated With Urgent Stenting (ICARUS)

Inclusion Criteria:

• A relevant clinical deficit defined as a National Institute of Health Stoke Scale (NIHSS) Score of ≥ 6 points for anterior circulation stroke and a NIHSS Score of ≥ 10 for posterior circulation stroke

• Patients presenting within 24 hours of last seen well to the treating hospital

• Occlusion of the Internal Carotid Artery, the M1 segment, the proximal/dominant M2segment of the Middle Cerebral Artery, the Basilar Artery or the V4 segment of theVertebral Artery

• Absence of recanalization (thrombolysis in myocardial infarction score of 0 or 1)after up to three endovascular treatment passes

• High probability of underlying intracranial atherosclerotic disease based on theassessment of the treating physician

• Age ≥ 18 years

• Occluded artery amendable to stenting by judgement of the treating physician

• Absence of a large infarct core defined as (posterior circulation) Alberta StrokeProgram Early CT Score of 6 or above

• Informed Consent as documented by signature or fulfilling the criteria for emergencyconsent procedures

Exclusion Criteria:

• Acute intracranial haemorrhage

• Pre-stroke modified Rankin Scale score of 2 or above

• Known, severe comorbidities, which will likely prevent improvement or follow-up (cancer, alcohol/drug abuse or dementia)

• Known clotting disease or suspicion of underlying disease which might lead to ahyper coagulant state

• In-hospital Stroke

• Known contraindications for anti-platelet therapy

• Known (serious) sensitivity to radiographic contrast agents, nickel, titanium metalsor their alloys

• Foreseeable difficulties in follow-up due to geographic reasons (e.g., patientsliving abroad)

• Evidence of an ongoing pregnancy prior to randomization

• Radiological confirmed evidence of mass effect or intracranial tumour (except smallmeningioma)

• Radiological confirmed evidence of cerebral vasculitis

• Evidence of vessel recanalization prior to randomisation

• Participation in another interventional trial which could confound the primaryendpoint