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. Presentation to enrolling hospital within 24 hours of last known well/stroke onset 4. Able to initiate arterial puncture within 2 hours from qualifying CTA/MRA or CTP/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 been performed. The exception is for LVO Mild deficit/Low NIHSS 0-5 for which imaging would only need to be repeated if there has been significant improvement in the NIHSS prior to randomization.

5. Has one of the following presentations:

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

7. Mild presenting neurologic deficits - NIHSS 0-5 (Must have some focalneurological deficit attributable to the target occlusion if NIHSS 0)

8. Complete occlusion of the intracranial Internal Carotid Artery (ICA) or M1Middle Cerebral Artery (MCA)

9. Medium/Distal Vessel Occlusion:

10. Visualized complete occlusion or perfusion deficit (Tmax > 4s) supportive of acortical branch occlusion in one of the following vessels:i) Non-dominant/Co-dominant M2 (defined as serving < 50% of entire overall MCAterritory) ii) M3

11. If symptom onset is > 6h, the core must be less than 50% of the territorysupplied by the occluded vessel as evident by either:i) Hypodensity and loss of grey-white border on NCCT or ii)ADC <620 mm2/s ondiffusion MRI or rCBF<30% on CTP

12. NIHSS > =8

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. Known or high suspicion for underlying intracranial atherosclerotic disease (ICAD)

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

13. Imaging

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

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

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

17. Tandem occlusions

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

19. Evidence of intra-cranial tumor (except small meningioma defined as (1) <=3 cm, (2) asymptomatic) as confirmed on CT/MRI)

20. Evidence of acute intracranial hemorrhage