Endovascular Therapy for Low NIHSS Ischemic Strokes

Inclusion Criteria:

1. Age 18 years or older

2. Acute ischemic stroke based on clinical diagnosis (NIHSS 0-5) and presence of anobjective neurological deficit

3. Patients eligible for intravenous rt-PA should receive this therapy as soon aspossible and no later than 4.5 hours from symptom onset

4. Proximal Intracranial Artery Occlusion on Imaging by NCCT/CTA or MRI/MRA showingcomplete occlusion of the intracranial ICA, M1, or an "M1-like" M2 vessel with orwithout tandem cervical lesion. Notably, "M1-like" M2 vessel occlusions are definedfunctionally for the trial as following:

5. On CTA: Occlusion of both branches after MCA division (both M2s occluded) orocclusion of the larger diameter M2 branch . In case of trifurcations, eitherthe two largest M2 branches are occluded or the occluded M2 has a largerdiameter than the combined diameter of the two other M2s . Notably, the M2origins are defined by the first branching point in the MCA other than theanterior temporal artery rather than by anatomic landmarks (e.g., horizontalversus insular location).or

6. If mCTA or CTP performed (optional): a M2 occlusion which supplies a largeproportion of the MCA territory by evidence of either: i. The bulk (>2/3) of the MCA territory has evidence of delayed washout onmultiphase CT or ii. Perfusion imaging shows a hypoperfusion lesion volume involvinga significant proportion of the MCA territory defined as Tmax >4 sec lesion of ≥100mL

7. Baseline Infarct Core of either:

8. Baseline ASPECTS ≥6 on non-contrast CT (NCCT), or

9. Baseline Infarct Core Volume of < 70cc on either CTP (Volume of rCBF <30%) orDWI if quantitative software tools are available (neither test is mandatory forstudy)

Exclusion Criteria:

1. NIHSS ≥6

2. Any sign of intracranial hemorrhage on baseline CT/MR (SDH/SAH/ICH)

3. Any imaging findings suggestive of futile recanalization in the judgment of thelocal investigator

4. High degree of suspicion of intracranial arterial disease (ICAD), such as evidenceof multifocal ICAD

5. Premorbid disability (mRS ≥3)

6. Inability to randomize within 8 hours of last known well

7. Seizures at stroke onset if it precludes obtaining an accurate baseline NIHSS

8. Baseline blood glucose of <50 mg/dL (2.78 mmol) or >400 mg/dL (22.20 mmol)

9. Known coagulation disorders as defined as platelet count <100,000/uL

10. Known renal failure as defined as serum creatinine levels > 3.0 mg/dL

11. Presumed septic embolus or suspicion of bacterial endocarditis

12. Any other condition that, in the opinion of the investigator, precludes anendovascular procedure or poses a significant hazard to the subject if anendovascular procedure was performed.

13. Participation in another investigational treatment study in the previous 30 days

14. Intubation and mechanical ventilation prior to study enrollment is medicallyindicated

15. History of drug or alcohol use or dependence that, in the opinion of the siteinvestigator, would interfere with adherence to study requirements

16. Site investigator does not have equipoise towards the ideal treatment concept (thrombectomy vs. best medical management)

17. Known pregnancy

18. Prisoner or incarceration

19. Known acute symptomatic COVID-19 infection