StrokeNet Thrombectomy Endovascular Platform

STEP PLATFORM INCLUSION CRITERIA:

1. Suspected diagnosis acute ischemic stroke

2. Likely causative intracranial large or medium vessel occlusion

STEP PLATFORM EXCLUSION CRITERIA:

1. Proven contraindication to endovascular thrombectomy

2. Prisoners/incarcerated

DOMAIN-SPECIFIC ELIGIBILITY CRITERIA:

Each domain may have additional eligibility criteria.

STEP EVT INDICATION EXPANSION DOMAIN INCLUSION CRITERIA:

1. Age 18 years or older 2. Pre-stroke modified Rankin Scale score 0-2 3. Presentationto enrolling hospital within 24 hours of last known well/stroke onset 4. Has one ofthe following presentations:

2. LVO patients with mild deficits/low NIHSS (must have both):

3. Mild presenting neurologic deficits - NIHSS 0-5

4. Occlusion of the intracranial Internal Carotid Artery (ICA) or M1 MiddleCerebral Artery (MCA)

5. Medium/Distal Vessel Occlusion (must have all 4):

6. Visualized occlusion or perfusion deficit supportive of a cortical branchocclusion (10 cc volume of Tmax >4s) in one of the following vessels: i)Non-dominant/Co-dominant M2 (defined as serving < 50% of entire overall MCAterritory) ii) M3 iii) M4 iv) A1 v) A2 vi) A3 vii) P1 viii) P2 ix) P3

7. Less than 50% core in the territory supplied by the occluded vessel as evidentby hypodensity and loss of grey-white border on NCCT or ADC <620 mm2/s ondiffusion MRI or rCBF<30% on CTP after 6h of symptom onset.

8. NIHSS > 4 or NIHSS 2-3 with clearly disabling deficits at presentation toenrolling hospital

9. Able to initiate arterial puncture within 2 hours from qualifying CTA/MRA orCTP/MRP imaging.

• CT/MR and qualifying CTA/MRA or CTP/MRP should be repeated if more than 120 minutes have elapsed since the imaging and randomization has not beenperformed.

STEP EVT INDICATION EXPANSION DOMAIN EXCLUSION CRITERIA:

1. Clinical

2. Presumed septic embolus; suspicion of bacterial endocarditis

3. Seizure at stroke onset or between onset and enrollment

4. Known anaphylactic reaction to contrast material that precludes endovascularreperfusion therapy

5. Intracranial occlusion suspected to be chronic, based on history and/or imaging

6. Intracranial dissection, based on history and/or imaging

7. Cerebral vasculitis, based on history and/or imaging

8. Known pregnancy

9. Known pre-existing medical, neurological or psychiatric disease that wouldconfound the neurological or functional evaluations

10. Known serious, advanced, or terminal illness or life expectancy less than 6months in the investigator judgment

11. Laboratory a. Known platelet count <100,000/uL

12. Imaging

13. CT ASPECT score <6 (MRI ASPECT score <7)

14. Unfavorable vascular anatomy that limits access to the occluded arteryprecluding endovascular reperfusion therapy.

15. Acute occlusions in multiple vascular territories (e.g., bilateral anteriorcirculation, or anterior/posterior circulation)

16. Significant mass effect with midline shift (>5mm)

17. Evidence of intra-axial tumor (except small meningioma)

18. Evidence of acute intracranial hemorrhage