The objective of this study is to assess the safety and effectiveness of mechanical thrombectomy (MT) using the ANA funnel catheter in its intended use, which is to facilitate the navigation and deployment of other neurovascular devices and to allow flow arrest during mechanical thrombectomy procedures performed in subjects experiencing acute ischemic stroke (AIS) secondary to large vessel occlusion (LVO) and treated within 24 hours of symptom onset.

Similar to other ancillary devices used in MT, the ANA device is designed to facilitate the delivery of stent retrievers and other catheters during these procedures. Its design aims to enhance procedural success and the efficiency of stent retriever-based MT by enabling flow arrest during clot retrieval. This approach has been shown to improve rates of revascularization and favorable clinical outcomes at three months.

The use of the ANA to facilitate MT with a stent retriever may provide a simplified approach to flow restriction and could achieve acute reperfusion outcomes comparable to commonly used strategies that combine direct aspiration with an intermediate catheter to actuate clot retrieval with a SR.

A dual-arm, prospective, randomized study will be conducted to demonstrate the safety and effectiveness of ANA compared to a conventional approach using cleared stent retrievers for MT. The study will report acute reperfusion success after a single thrombectomy pass with three of the most commonly employed stent retrievers: Solitaire, Trevo, and pRESET. Procedural safety will be assessed by comparing the rate of procedure-related sICH within 24 hours of the intervention between study arms.

Key Inclusion Criteria:

Subjects meeting all inclusion criteria will be considered for enrollment in the study.

1. Age 22 to 85 years.

2. Informed consent was obtained from subject or acceptable subject surrogate (e.g., next of kin, or legal representative).

3. A new focal disabling neurologic deficit consistent with acute cerebral ischemia.

4. Baseline NIHSS obtained prior to procedure ≥ 6 points and ≤ 25 points.

5. Pre-ictal mRS score of 0,1 or 2.

6. Treatable within 16 hours of symptom onset, defined as point in time when the subject was last observed to be asymptomatic; treatment start is defined by arterial puncture time.

7. 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.

8. Occlusion (eTICI ≤ 1 flow) of the terminal carotid artery, middle cerebral artery M1 segment or, dominant or proximal M2 segment, indicated for mechanical thrombectomy, confirmed with conventional angiography or CTA/MRA.

9. Imaging criteria:

   • Perfusion weighted criterion: volume of diffusion restriction visually assessed

     ≤ 50 mL on CTP/MRP, or

   • CT criterion: Alberta Stroke program early CT score (ASPECTS) 6 to 10 on baseline CT/DWI-MRI. (Inclusion of subjects with ASPECTS 5 is permitted at centers performing scoring on MRI)

10. The subject is indicated for a neurovascular thrombectomy procedure with an approved stent retriever per its Instructions for Use.

Key Exclusion Criteria:

Subjects who meet any of the exclusion criteria will be ineligible for participation in the study.

The following exclusion criteria will be assessed pre-operatively:

1. Subject was diagnosed with a stroke in the past year.
2. Clinical symptoms suggestive of bilateral stroke or stroke in multiple territories.
3. Known hemorrhagic diathesis, coagulation factor deficiency, oral anticoagulant therapy with antivitamin K, with INR >3.0, or thrombocytopenia - baseline platelet count < 50,000 platelets/mL.
4. Known baseline glucose of <50 mg/dL or >400 mg/dL.
5. Severe, sustained uncontrolled hypertension refractory to treatment (systolic blood pressure >185 mmHg or diastolic blood pressure >110 mmHg).
6. Serious, advanced, or terminal disease with anticipated life expectancy of less than 1 year.
7. Known cancer with metastases.
8. History of life-threatening allergy (more than rash) to contrast medium.
9. Known renal insufficiency with creatinine ≥3 mg/dL or glomerular filtration rate (GFR) <30 mL/min.
10. Subject is a current user or has a recent history of cocaine &/or heroin use.
11. Known pregnancy and/or lactating female.
12. Subject is participating in a concurrent study involving an investigational drug or device that would impact the primary endpoint of this study.
13. Subject is unlikely to be available for a 90-day follow-up (e.g. no fixed home address, visitor from overseas, etc.)
14. CT or MRI evidence of hemorrhage (the presence of microbleeds is allowed).
15. Significant mass effect with midline shift.
16. Evidence of intracranial tumor (except asymptomatic meningioma of ≤ 2cm in diameter).
17. Suspicion of aortic dissection, presumed septic embolus, or suspicion of bacterial endocarditis.
18. History of preexisting stent proximal to or at the occlusion site that may preclude safe deployment or recovery of the stent retriever.
19. Vessel tortuosity too difficult to allow endovascular access of the intracranial ICA per investigator judgement. Indicators of vessel tortuosity include but are not limited to the presence of carotid loops and type 3 aortic arches.