Evaluation of Mechanical Thrombectomy in Acute Ischemic Stroke Related to a Distal Arterial Occlusion

Mechanical thrombectomy (MT) has shown its effectiveness for the treatment of acute ischemic stroke (AIS) related to large vessel occlusion and rapidly became a cornerstone in the management of these patients. No strong evidence is available on the benefit of MT in AIS related to more distal occlusions. Some previous observational studies suggested a possible benefit but most of them were single-centre and retrospective studies providing a very low level of evidence. To date, no randomized controlled trial has been conducted in this indication, which represents 10% to 20% of all AIS involving intracranial vessel occlusions.

This research is a multicenter open randomized controlled trial with two parallel groups : best medical treatment alone VS mechanical trombectomy + best medical treatment.

The main objective of this trial is to assess the efficacy of mechanical thrombectomy in addition to the best medical treatment as compared to the best medical treatment alone in AIS related to a distal intracranial artery occlusion. The medical device used will be a stent retriever among : Trevor NXT ProVue Retriever ; Catchview mini ; pReset Lite ; Tigertriever13, and the medical treatment used will depend on the stroke's etiology and will consist of IV trhombolysis or tenecteplase or antiplatelet therapy or anticoagulant therapy ... The main inclusion criteria are : 1) patients aged ≥ 18 years ; 2) Delay between symptoms onset and expected groin puncture ≤ 6h ; 3) Symptomatic occlusion as evaluated by a National Institute of Health Stroke Score (NIHSS) ≥ 5 ; 4) Distal occlusion evaluated on CT angiography (CTA) or magnetic resonance imaging (MRI) and defined as an occlusion in one of the following segments : a-Distal M2, above the mid-height of the insula, b-M3 segment, c-Posterior cerebral artery (PCA) = P1, P2 or P3 segment, d-Anterior cerebral artery (ACA) : A1, A2 or A3 segment ; 5) Written informed consent signed by the patient or the trustworthy person / family member / close relative, or inclusion in case of emergency and written informed consent will be signed by the patient (if needed by trustworthy person, family member or close relative) as soon as possible (article L1122-1-2 of the French Public Health Code).

The secondary objectives and endpoints are to evaluate the : 1) Success of the procedure defined as recanalization of the occluded vessel, evaluated on the AOL (Arterial Occlusion Lesion) score within 48 hours ; 2) Excellent clinical outcome (defined as a modified Rankin scale \[mRS\]≤1) at 3 months ; 3) Safety with reporting of all adverse and serious adverse events with a particular attention to perforation rate, embolus migration in a new territory and symptomatic hemorrhagic complications ; 4) Death rate up to 3 months ; 5) Cost effectiveness and utility of the procedure. The study will also evaluate the rate of angiographic reperfusion in the intervention group on the final angiogram at the end of the MT (which is part of the intervention) using the modified thrombolysis in cerebral infarction (mTICI) (2B-3) and the eTICI.

Eligibility Criteria:
Inclusion Criteria:

* Patients aged ≥ 18 years
* Delay between symptoms onset and expected groin puncture ≤ 6 h
* Symptomatic occlusion as evaluated by a National Institute of Health Stroke Score (NIHSS) ≥ 5
* Distal occlusion evaluated on CT angiography (CTA) or magnetic resonance imaging (MRI) and defined as an occlusion in one of the following segments:

  * Distal M2, above the mid-height of the insula
  * M3 segment
  * Posterior cerebral artery (PCA): P1, P2, P3 segments
  * Anterior cerebral artery (ACA): A1, A2, A3 segments
* Written informed consent signed by the patient or the trustworthy person / family member / close relative, or inclusion in case of emergency and written informed consent will be signed by the patient (if needed by trustworthy person, family member or close relative) as soon as possible (article L1122-1-2 of the French Public Health Code)

Exclusion Criteria:

* Pregnancy or breastfeeding woman
* Contra-indication for femoral, radial or humeral arterial puncture
* Tandem occlusion (i.e.: concomitant cervical and intra-cranial arterial occlusion)
* Allergy to iodinated contrast media
* Known renal insufficiency (confirmed by previous result of creatinine clearance \< 30 ml/min)
* Secondary distal occlusion (i.e., complicating a MT for a proximal occlusion, or any other endovascular intracranial procedure)
* Aortic dissection
* Asymptomatic or minor stroke (i.e.: NIHSS \< 5)
* Pretreatment mRS \> 1 (pre-stroke)
* Anticipated limitations for anesthesia
* Participation in another trial (Jardé 1 and Jardé 2)
* Absence of affiliation to National French social security system
* Under legal protection measure (tutorship or curatorship) and patient deprived of freedom
* A pre-existing hemorrhage in the brain tissue fed by the target vessel
* Known hypersensitivity to nickel/titanium
* Stenosis and/or with a stent proximal to the site of the thrombus which could preclude the retrieval of the stent retriever
* Angiographic evidence of carotid dissection