Friday, March 16, 2018

Endovascular Therapy for Strokes

R.E.B.E.L.EM - March 15, 2018 - By Salim Rezaie
Clinical Take Home Point: 
  • Systemic IV thrombolysis can have limited responsiveness (13 – 50%) to large thrombi in the central circulation, a narrow time window for administration (4.5hrs), and increases the risk of cerebral/systematic hemorrhage
  • The initial 3 trials showing no difference in 90d mRs scores were most likely due to:
    • Proximal occlusion not radiologically proven with intracranial occlusions (i.e. CTA, MRA)
    • The use of first-generation Merci devices as opposed to retrievable stents
    • It is also important to note that in many of the earlier trials there were more new strokes and vessel dissections compared to systemic therapy
  • In the studies reviewed, recruitment averaged about 1 patient per month, meaning this was a very specific and particular patient that was recruited
  • As more and more trials have been performed, the efficiency, the type of imaging, and technology have all also improved, minimizing complications and improving efficacy of endovascular therapy
  • Endovascular therapy for ischemic stroke is suitable for patients with ischemic stroke within 24hrs of symptom onset, with:
    • Proof of proximal intracranial vessel occlusion
    • Imaging methods to exclude large infarct cores
    • Efficient workflow to achieve fast recanalization and high reperfusion rates
    • Workflow: Ischemic Stroke Symptoms ≤24hrs -> CT/CTA -> If CTA positive for large anterior (ICA/MCA) stroke -> CT or MR Perfusion Scan to determine eligibility for Endovascular Therapy
  • Later trials included patients with “wake up” strokes, which have not previously been included in systemic t-PA trials
  • One final note: It is important to realize that many trials were stopped early, and because of this the magnitude of benefit for endovascular therapy may be over inflated in many of these trials