The Imperative Trial: Treatment of Acute Ischemic Stroke With the Zoom Reperfusion System

Inclusion Criteria:

1. Age 18 and older
2. NIHSS \>=6
3. The operator feels that the stroke can be treated with endovascular thrombectomy approaches and the interventionalist estimates that groin puncture can be achieved within 8 hours from time last seen well
4. Pre-event mRS scale 0-1
5. Large vessel occlusion of the intracranial internal carotid artery (ICA), middle cerebral artery (MCA)-M1 or M2 segments, basilar, or vertebral arteries as evidenced by MRA or CTA
6. For strokes in anterior circulation, ASPECTS \>=6; For strokes in posterior circulation, pc-ASPECTS \>=8
7. Non-contrast CT/CTA or MRI/MRA for trial eligibility performed or repeated at treating stroke center or outside medical facility within 2 hours of treatment initiation
8. If indicated per American Heart Association clinical guidelines, thrombolytic therapy should be administered as soon as possible
9. Consenting requirements met according to local IRB or Ethics Committee

Exclusion Criteria:

1. Female known to be pregnant at time of admission
2. Patient has suffered a stroke in the past 3 months
3. Presence of an existing or pre-existing large territory infarction
4. Pre-existing neurological or psychiatric disease that would confound the neurological or functional evaluation, e.g., dementia with prescribed anti-cholinesterase inhibitor
5. Known history of severe contrast allergy or absolute contraindication to iodinated contrast
6. Clinical history, past imaging or clinical judgement suggest that the intracranial occlusion is chronic
7. Life expectancy of less than 6 months prior to stroke onset
8. Clinical symptoms suggestive of bilateral stroke or stroke in multiple territories
9. Subject participating in another clinical trial involving an investigational device or drug
10. Known cancer with metastases
11. Evidence of active systemic infection
12. Any known hemorrhagic or coagulation deficiency

Imaging Exclusion Criteria:
13. Evidence of intracranial hemorrhage on CT/MRI
14. CTA or MRA evidence of carotid stenosis requiring treatment for intracranial access
15. Excessive vascular access tortuosity or target vessel size that will likely prevent endovascular access with the Imperative Care 0.088" ID Catheters
16. Intracranial stent implanted in the same vascular territory that would preclude the safe deployment/removal of the thrombectomy devices
17. Occlusions in multiple vascular territories (e.g., bilateral anterior circulation, or anterior circulation/vertebrobasilar system) as confirmed on CTA/MRA, or clinical evidence of bilateral strokes or strokes in multiple territories as determined by the treating physician
18. Significant mass effect with midline shift as confirmed on CT/MRI
19. Evidence of intracranial tumor (except small meningioma defined as ≤ 3cm and asymptomatic) as confirmed on CT/MRI
20. Angiographic evidence of pre-existing arterial injury, e.g., carotid dissection, complete cervical carotid occlusion, or vasculitis