Table 2

Detailed study inclusion and exclusion criteria

Inclusion criteriaExclusion criteria
Randomised controlled trial
  1. Age 18–85;

  2. Clinical signs consistent with AIS; NIHSS ≥6 and <30 at the time of randomisation

  3. Pre-stroke mRS ≤1;

  4. Persistent symptoms within 8 hours from the time point of groin puncture;

  5. Imaging demonstrated by MR or CT: core infarct lesion volume <70 mL, or ASPECTS ≥6 and ≤10

  6. Large vessel occlusion of anterior circulation demonstrated by DSA (intracranial carotid artery, M1 or M2 MCA, and A1 or A2 ACA)

  7. Subjects who meet the requirements have received/are receiving the correct IV-tPA dose within 4.5 hours of onset of stroke symptoms;

  8. Subjects or legal representatives should be able to understand the purpose of the experiments, have signed voluntarily the informed consent and should be willing to conduct protocol-required follow-up visits.

  1. Life expectancy may be <90 days;

  2. Women who are pregnant or breast feeding, or who plan to give birth within the next 90 days;

  3. Allergic to contrast agents, nickel–titanium metals or their alloys;

  4. Suspected renal failure defined as serum creatinine >3.0 mg/dL (or 264 µmol/L) or GFR <30 mL/min;

  5. Severe persistent hypertension that cannot be controlled by medication defined as systolic blood pressure >185 mm Hg or diastolic blood pressure <110 mm Hg;

  6. Active bleeding or known bleeding;

  7. Platelet count <50×109 /L;

  8. RBG <50 mg/dL (2.78 mmol/L) o r>400 mg/dL (22.20 mmol/L);

  9. Subjects with occlusion of multiple vascular areas (eg, bilateral anterior circulation or anterior/posterior circulation);

  10. CT or MRI evidence of intracranial haemorrhage or infarction involving greater than 1/3 of MCA territory (or in other territories, >70 mL of tissue on presentation);

  11. Angiographic evidence of cervical carotid occlusion due to carotid dissection or arteritis;

  12. Angiographic evidence of vessels corresponding to severely tortuous arteries for assessing the ability of group/control group devices to reach the target vessels or to be recycled;

  13. Evidence of vessel occlusion caused by septic embolism or bacterial endocarditis;

  14. CT or MRI evidence of intracranial tumour (with the exception of small meningioma);

  15. Subjects who had a stroke in the past 3 months;

  16. Subjects who had a heart, lung and kidney function failure and other serious organic diseases;

  17. Other unsuitable conditions for inclusion assessed by the researchers.

Small sample study
  1. Age 18–85;

  2. Clinical signs consistent with AIS; NIHSS ≥6 and <30 at the time of randomisation

  3. Pre-stroke mRS ≤1;

  4. Persistent symptoms between 8 and 24 hours from the time point of groin puncture;

  5. The imaging methods should adhere to the ‘Clinical-Imaging Mismatch’ (core infarct lesion volume mismatch of baseline NIHSS score and MRI-DWI/CTP-rCBF) and are defined as follows: age 80–85, NIHSS ≥10 and core infarct lesion volume <21 mL; age <80, NIHSS ≥10 and core infarct lesion volume <31 mL and core infarct lesion volume ≥31 mL and <51 mL;

  6. Large vessel occlusion of anterior circulation demonstrated by DSA (intracranial carotid artery, M1 or M2 MCA, and A1 or A2 ACA);

  7. Subjects who meet the requirements should have received/are receiving the correct IV-tPA dose within 4.5 hours of the onset of stroke symptoms.

  • ACA, anterior cerebral artery; AIS, acute ischaemic stroke; ASPECTS, Alberta stroke program early CT score; DSA, digital subtraction angiography; GFR, glomerular filtration rate; IV-tPA, intravenous tissue plasminogen activator; MCA, middle cerebral artery; MRI-DWI/CTP-rCBF, MRI-diffusion-weighted imaging/CT perfusion-relative cerebral blood flow; mRS, modified Rankin Scale; NIHSS, National Institutes of Health Stroke Scale; RBG, random blood glucose; tPA, tissue plasminogen activator.