Inclusion Criteria:
1. 18 to 80 years of age
2. Presenting with symptoms consistent with AIS
3. Imaging evidence of an anterior occlusion of the Internal Carotid Artery (ICA) or Middle Cerebral Artery Main Stem (MCA M1), or proximal M2 segment AND residual 70-99% stenosis of the index artery following attempted clot retrieval with either aspiration catheters or stent retrievers, per device instructions for use and device labeling
4. NIHSS ≥ 6
5. Ability to randomize within 24 hours of stroke onset.
6. Pre-stroke mRS score 0-2
7. Ability to obtain signed informed consent.
8. ASPECTS Score ≥ 6 by non-contrast CT scan
9. Score-ICAD score of ≥11 points at screening and/or persistent stenotic occlusion of ≥70% after MT
10. If indicated, thrombolytic therapy shall be initiated per the institution's usual care and the most recent version of the AHA/ASA Guidelines. Subjects eligible for IV thrombolysis should receive it without delay.
11. For subjects presenting \>6 hours from stroke onset, infarct core volume \<50 cc quantified by CTP
Exclusion Criteria:
1. Females who are pregnant, or those of child-bearing potential with positive urine or serum beta Human Chorionic Gonadotropin (HCG) test
2. Known severe allergy (more than a rash) to contrast media uncontrolled by medications.
3. CT evidence of the following conditions:
* Midline shift or herniation
* Evidence of intracranial hemorrhage
* Mass effect with effacement of the ventricles
4. Acute bilateral strokes
5. Contraindication to antiplatelet (aspirin, clopidogrel, ticagrelor, cangrelor) or contrast agents
6. Intracranial tumors other than small meningioma, that do not require surgery for at least one year post randomization. Small meningioma is defined as a lesion measuring ≤20mm in maximum diameter or ≤4cm3 in volume, with no associated mass effect, peritumoral edema, or progressive neurological symptoms
7. Known hemorrhagic diathesis, coagulation factor deficiency, or on anticoagulant therapy with an International Normalized Ratio (INR) of \>3.0 or Partial Thromboplastin Time (PTT) \>3 times of normal
8. Baseline platelet count \<80,000 per microliter (µl)
9. Life expectancy less than one year prior to stroke onset
10. Participation in another randomized clinical trial that could confound the evaluation of the study outcomes.
11. Any other condition (in the opinion of the site investigator) that precludes an endovascular procedure or poses a significant hazard to the patient if an endovascular procedure was performed
12. New diagnosis of atrial fibrillation or a history of atrial fibrillation
13. Suspected device-induced vasospasm defined as smooth transient narrowing of the target vessel
14. Vessel dissection including any of the following: presence of dissection flap, false lumen, contrast stagnation in the vessel wall, and/or improving stenosis
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