Key Terms: Endovascular therapy (EVT), Mechanical Thrombectomy, Large Vessel Occlusion, CT-Perfusion, Perfusion Mismatch

Hosts: Ryan Muir, Tess Fitzpatrick, Houman Khosravani

Summary:

• What is endovascular therapy?
  

• What were the early trials of EVT – what did we learn from them?
  

  • MULTI – MERCI
    
  • PENUMBRA PIVOTAL
    
  • IMS-III
    
• MR. RESCUE
• Modified Rankin Scale (MRS) at 90 days).
  

• These trials were summarized in a meta-analysis performed by the HERMES in collaboration in 2016.
  

  • MR. CLEAN
    
  • ESCAPE
    
  • REVASCAT
    
  • SWIFT PRIME
    
  • EXTEND IA
    
• In the HERMES pooled analysis the number needed to treat with EVT was 2.6 persons to reduce MRS by 1 point.
  
• One trial was done later also favoured EVT, but was not included in the HERMES meta-analysis - the THRACE trial

• DAWN
• DEFUSE 3

• As a result of DAWN and DEFUSE 3, the 2019 AHA/ASA Guidelines now suggest:
  

  • Within 0 – 6 hours of symptom onset: Direct aspiration thrombectomy as a first pass or mechanical thrombectomy with a stent retriever should be done if the following criteria are met: (i) prestroke MRS of 0 – 1 (ii) causative occlusion of the internal carotid artery or MCA segment 1 (M1) (iii) age >18 years (4) NIHSS ≥ 6
    
  • Within 6 – 24 hours of symptom onset
    
• In selected patients with acute ischemic stroke within 6 – 16 hours of last known normal who have a large vessel occlusion in the anterior circulation and meet other DAWN or DEFUSE 3 eligibility criteria, mechanical thrombectomy is recommended
• In selected patients with acute ischemic stroke within 6 – 24 hours of last known normal who have a large vessel occlusion in the anterior circulation and meet other DAWN eligibility criteria, mechanical thrombectomy is reasonable