Please select the eligibility criteria that correspond to the clinical trial below.
Title: Randomization of Endovascular Treatment With Stent-retriever and/or Thromboaspiration vs. Best Medical Therapy in Acute Ischemic Stroke Due to Large VEssel OcclusioN Trial
Brief Summary: Prospective, multi-center, randomized, controlled, open, blinded-endpoint trial with a sequential design. The randomization employs a 1:1 ratio of mechanical thrombectomy with stentriever and/or Thromboaspiration versus medical management alone. Randomization will be done under a minimization process using age, baseline NIHSS, use of IV tpa, vessel occlusion site and hospital. To evaluate the hypothesis that mechanical thrombectomy is superior to medical management alone in achieving more favorable outcomes in the distribution of the modified Rankin Scale scores at 90 days in subjects presenting with acute large vessel ischemic stroke \<8 hours from symptom onset. Subjects are either ineligible for IV alteplase or have received IV alteplase therapy without recanalization. Sample size is projected to be 690 patients for a difference in treatment effect of 10%.


Options:
A: Inclusion Criteria:

1. Age ≥18 years;
2. Acute ischemic stroke consistent with infarction in the basilar artery territory;
3. Basilar artery occlusion confirmed by CTA/MRA/DSA, within 8 hours of estimated occlusion time;
4. Written informed consent from patient or surrogate, if unable to provide consent.

Exclusion Criteria:

1. Computed tomography (CT) or Magnetic Resonance Imaging (MRI) evidence of Cerebral hemorrhage on presentation;
2. Premorbid mRS ≥ 3 points;
3. Currently in pregnant or lactating;
4. Known serious sensitivity to radiographic contrast agents and nitinol metal;
5. Current participation in another investigation drug or device study;
6. Uncontrolled hypertension defined as systolic blood pressure \> 185 mmHg or diastolic blood pressure \> 110 mmHg that cannot be controlled except with continuous parenteral antihypertensive medication;
7. Known hereditary or acquired hemorrhagic diathesis, coagulation factor deficiency; or oral anticoagulant therapy with INR \>1.7 or institutionally equivalent prothrombin time;
8. Baseline lab values: glucose \< 50 mg/dl or \> 400 mg/dl, platelets \<100\*109/L, or Hct\<25%;
9. Arterial tortuosity that would prevent the device from reaching the target vessel;
10. Life expectancy less than 1 year;
11. History of major hemorrhage in the past 6 months;
12. Angiographic evidence of significant cerebellar mass effect or acute hydrocephalus.
13. Angiographic evidence of bilateral extended brainstem ischemia.
B: Inclusion Criteria:

1. Acute ischemic stroke where patient is ineligible for IV thrombolytic treatment or the treatment is contraindicated (e.g., subject presents beyond recommended time from symptom onset), or where patient has received IV thrombolytic therapy without clinical improvement.
2. No significant pre-stroke functional disability (mRS ≤ 1)
3. Baseline NIHSS score obtained prior to randomization must be equal or higher than 8 points
4. Age ≥18 years
5. Occlusion (TICI 0-1) of the intracranial ICA (distal ICA or T occlusions) and/or MCA-M1 segment suitable for endovascular treatment, as evidenced by CTA, MRA or angiogram, with or without concomitant cervical carotid occlusion or stenosis.
6. Patient treatable within eight hours of symptom onset. Symptoms onset is defined as point in time the patient was last seen well (at baseline). Treatment start is defined as groin puncture.
7. Informed consent obtained from patient or acceptable patient surrogate

Exclusion Criteria:

1. Known hemorrhagic diathesis, coagulation factor deficiency, or oral anticoagulant therapy with INR \> 3.0
2. Baseline platelet count \< 30.000/µL
3. Baseline blood glucose of \< 50mg/dL or \> 400mg/dl
4. Severe, sustained hypertension (SBP \> 185 mm Hg or DBP \> 110 mm Hg) NOTE: If the blood pressure can be successfully reduced and maintained at the acceptable level using AHA guidelines recommended medication (including iv antihypertensive drips), the patient can be enrolled.
5. Patients in coma (NIHSS item of consciousness \>1) (Intubated patients for transfer could be randomized only in case an NIHSS is obtained by a neurologist prior transportation).
6. Seizures at stroke onset which would preclude obtaining a baseline NIHSS
7. Serious, advanced, or terminal illness with anticipated life expectancy of less than one year.
8. History of life threatening allergy (more than rash) to contrast medium
9. Subjects who has received IV t-PA treatment beyond 4,5 hours from the beginning of the symptoms
10. Woman of childbearing potential who is known to be pregnant or lactating or who has a positive pregnancy test on admission.
11. Subject participating in a study involving an investigational drug or device that would impact this study.
12. Cerebral vasculitis
13. Patients with a pre-existing neurological or psychiatric disease that would confound the neurological or functional evaluations, mRS score at baseline must be ≤1. This excludes patients who are severely demented, require constant assistance in a nursing home type setting or who live at home but are not fully independent in activities of daily living (toileting, dressing, eating, cooking and preparing meals, etc.)
14. Unlikely to be available for 90-day follow-up (e.g. no fixed home address, visitor from overseas).
15. Hypodensity on CT or restricted diffusion amounting to an ASPECTS score of \<6 on NCCT, or \<5 on DWI MRI. The use of CTP or MRI perfusion is optional.
16. Collaterals with malignant profile on CTA (without colateral circulation on CTA)
17. CT or MR evidence of hemorrhage (the presence of GRE microbleeds is allowed).
18. Significant mass effect with midline shift.
19. Evidence of ipsilateral carotid occlusion, high grade stenosis or arterial dissection in the extracranial or petrous segment of the internal carotid artery that cannot be treated or will prevent access to the intracranial clot or excessive tortuosity of cervical vessels precluding device delivery/deployment
20. Subjects with occlusions in multiple vascular territories (e.g., bilateral anterior circulation, or anterior/posterior circulation)
21. Evidence of intracranial tumor (except small meningioma).
C: General Inclusion Criteria:

1. Clinical signs and symptoms consistent with the diagnosis of an acute ischemic stroke, and subject belongs to one of the following subgroups:

   1. Subject has failed IV t-PA therapy (defined as a confirmed persistent occlusion 60 min after administration)
   2. Subject is contraindicated for IV t-PA administration
2. Age ≥18
3. Baseline NIHSS ≥10 (assessed within one hour of measuring core infarct volume)
4. Subject can be randomized between with 6 to 24 hours after time last known well
5. No significant pre-stroke disability (pre-stroke mRS must be 0 or 1)
6. Anticipated life expectancy of at least 6 months
7. Subject willing/able to return for protocol required follow up visits
8. Subject or subject's Legally Authorized Representative (LAR) has signed the study Informed Consent form\*

   * If approved by local ethics committee and country regulations, the investigator is allowed to enroll a patient utilizing emergency informed consent procedures if neither the patient nor the representative or person of trust is available to sign the informed consent form. However, as soon as possible, the patient is informed and his/her consent is requested for the possible continuation of this research. (Not applicable to U.S. Sites.)

Imaging Inclusion Criteria:

1. \< 1/3 MCA territory involved, as evidenced by CT or MRI
2. Occlusion of the intracranial ICA and/or MCA-M1 as evidenced by MRA or CTA
3. Clinical Imaging Mismatch (CIM) defined as one of the following on MR-DWI or CTP-rCBF maps:

   1. 0-\<21 cc core infarct and NIHSS ≥ 10 (and age ≥ 80 years old)
   2. 0-\<31 cc core infarct and NIHSS ≥ 10 (and age \< 80 years old)
   3. 31 cc to \<51 cc core infarct and NIHSS ≥ 20 (and age \< 80 years old)

General Exclusion Criteria:

1. History of severe head injury within past 90 days with residual neurological deficit, as determined by medical history
2. Rapid improvement in neurological status to an NIHSS \<10 or evidence of vessel recanalization prior to randomization
3. Pre-existing neurological or psychiatric disease that would confound the neurological or functional evaluations, e.g. dementia with prescribed anti-cholinesterase inhibitor (e.g. Aricept)
4. Seizures at stroke onset if it makes the diagnosis of stroke doubtful and precludes obtaining an accurate baseline NIHSS assessment
5. Baseline blood glucose of \<50mg/dL (2.78 mmol) or \>400mg/dL (22.20 mmol)
6. Baseline hemoglobin counts of \<7 mmol/L
7. Baseline platelet count \< 50,000/uL
8. Abnormal baseline electrolyte parameters as defined by sodium concentration \<130 mmol/L, potassium concentration \<3 mEq/L or \>6 mEq/L
9. Renal failure as defined by a serum creatinine \>3.0 mg/dL (264 µmol/L) NOTE: subjects on renal dialysis may be treated regardless of serum creatinine levels
10. Known hemorrhagic diathesis, coagulation factor deficiency, or on anticoagulant therapy with INR \> 3.0 or PTT \> 3 times normal. Patients on factor Xa inhibitor for 24-48 hours ago must have a normal PTT.
11. Any active or recent hemorrhage within the past 30 days
12. History of severe allergy (more than rash) to contrast medium
13. Severe, sustained hypertension (Systolic Blood Pressure \>185 mmHg or Diastolic Blood Pressure \>110 mmHg) NOTE: If the blood pressure can be successfully reduced and maintained at the acceptable level using medication the subject can be enrolled
14. Female who is pregnant or lactating at time of admission
15. Current participation in another investigational drug or device study
16. Presumed septic embolus, or suspicion of bacterial endocarditis
17. Treatment with any cleared thrombectomy devices or other intra-arterial (neurovascular) therapies prior to randomization

Imaging Exclusion Criteria:

1. Evidence of intracranial hemorrhage on CT/MRI
2. CTA or MRA evidence of flow limiting carotid dissection, high-grade stenosis, or complete cervical carotid occlusion requiring stenting at the time of the index procedure (i.e., mechanical thrombectomy).
3. Excessive tortuosity of cervical vessels on CTA/MRA that would likely preclude device delivery/deployment
4. Suspected cerebral vasculitis based on medical history and CTA/MRA
5. Suspected aortic dissection based on medical history and CTA/MRA
6. Intracranial stent implanted in the same vascular territory that would preclude the safe deployment/removal of the Trevo device
7. 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
8. Significant mass effect with midline shift as confirmed on CT/MRI
9. Evidence of intracranial tumor (except small meningioma) as confirmed on CT/MRI
D: Inclusion Criteria:

1. Patients presenting with anterior circulation acute ischaemic stroke eligible using standard criteria to receive IV tPA within 4.5 hours of stroke onset
2. Patient, family member or legally responsible person depending on local ethics requirements has given informed consent
3. Patient"s age is ≥18 years
4. Intra-arterial clot retrieval treatment can commence (groin puncture) within 6 hours of stroke onset.

   Imaging inclusion criteria

   Dual target:
5. Arterial occlusion on CTA or MRA of the ICA, M1 or M2
6. Mismatch - Using CT or MRI with a Tmax \>6 second delay perfusion volume and either CT-rCBF or DWI infarct core volume. a) Mismatch ratio of greater than 1.2, and b) Absolute mismatch volume of greater than 10 ml, and. c) Infarct core lesion volume of less than 70mL

Exclusion Criteria:

1. Intracranial haemorrhage (ICH) identified by CT or MRI
2. Rapidly improving symptoms at the discretion of the investigator
3. Pre-stroke mRS score of ≥ 2 (indicating previous disability)
4. Inability to access the cerebral vasculature in the opinion of the neurointerventional team
5. Contra indication to imaging with MR with contrast agents
6. Participation in any investigational study in the previous 30 days
7. Any terminal illness such that patient would not be expected to survive more than 1 year
8. Any condition that, in the judgment of the investigator could impose hazards to the patient if study therapy is initiated or affect the participation of the patient in the study.
9. Pregnant women
10. Previous stroke within last three months
11. Recent past history or clinical presentation of ICH, subarachnoid haemorrhage (SAH), arterio-venous (AV) malformation, aneurysm, or cerebral neoplasm. At the discretion of each Investigator.
12. Current use of oral anticoagulants and a prolonged prothrombin time (INR \> 1.6)
13. Use of heparin, except for low dose subcutaneous heparin, in the previous 48 hours and a prolonged activated partial thromboplastin time exceeding the upper limit of the local laboratory normal range.
14. Use of glycoprotein IIb - IIIa inhibitors within the past 72 hours. Prior use of single or dual agent oral platelet inhibitors (clopidogrel and/or low-dose aspirin) is permitted.
15. Clinically significant hypoglycaemia.
16. Uncontrolled hypertension defined by a blood pressure \> 185 mmHg systolic or \>110 mmHg diastolic on at least 2 separate occasions at least 10 minutes apart, or requiring aggressive treatment to reduce the blood pressure to within these limits. The definition of "aggressive treatment" is left to the discretion of the responsible Investigator.
17. Hereditary or acquired haemorrhagic diathesis
18. Gastrointestinal or urinary bleeding within the preceding 21 days
19. Major surgery within the preceding 14 days which poses risk in the opinion of the investigator.
20. Exposure to a thrombolytic agent within the previous 72 hrs

Answer: B