Topic 1 - Summary
1. Citation:

Multicenter Randomized Clinical Trial of Endovascular Treatment for Acute Ischemic Stroke in the Netherlands (MR CLEAN)

2. Summary/Bottom Lines:
  • Description:

    • Pragmatic, Phase III, Multicenter (16) Clinical Trial- Conducted Dec 2010-Mar 2014.
    • Open-label treatment with blinded end-point evaluation.

    Research Question:

    • Assessed whether Intra-arterial therapy (consisted of arterial cath with a microcatheter to the level of the occlusion & delivery of thrombolytic agent, mechanical thrombectomy (thrombus retraction, aspiration, wire disruption, or use of retrievable stents), or both) plus usual care (IV Alteplase/Urokinase) is more effective than usual care alone in patients with proximal arterial occlusion in anterior cerebral circulation that could be treated intraarterially within 6 hrs of symptom onset.
3. Methods:
  • Outcome: Functional

    • Primary Outcome: Modified Rankin Scale Score at 90 days (7 point scale ranging from 0 (no Symptoms)- 6 (Death)- A score of 2 or less indicates functional independence).
    • Secondary Outcomes:
      • NIHSS score at 24 hrs, 5-7 d, or at discharge (Compared to initial presentation).
      • ADL measured via Barthel Index.
      • Health-related quality of life measured with EuroQol Group 5 at 90 days.
      • Baseline evaluated with noncontrast CT for Albetrta Stroke Program Early CT Score.
      • Recanalization measured with CTA or MRA at 24 hrs- classified as complete or not & further evaluated with use of the Modified Arterial Occlusive Lesion Score.
      • Final infarct volume on F/U noncontrast CT was assessed at 5-7 days w/use of Modified Thrombolysis in Cerebral Infarction score (TICI).


    • Primary outcome:
      • Better outcome in the intervention group in all categories of Modified Rankin scale.
      • The absolute between-group difference in the proportion of patients who were functionally independent was 13.5 % points (95% CI, 5.9 to 21.2) with an adjusted odds ratio of 2.16 (95% CI, 1.39 to 3.38).
      • In the control group only 1 pt had a modified Rankin score of 0.
      • Secondary outcomes:
        • NIHSS was 2.9 (95%CI, 1.5-4.3) lower in intervention group compared to control.
        • Recanalization Data- Complete recanalization was more common in intervention group (141 out of 187 pts 75.4%) than in control group (68 of 207 pts 32.9%).
        • Infarct volume- 19ml difference (95% CI, 3 to 34) in favor for intervention group.
        • Reperfusion (modified TICI score) achieved in 115 of 196 pts in intervention group.
        • There is significant increase in functional independence w/out increase in mortality for the intervention group than the control group.

    Complications/Safety Issues:

    • Serious adverse events - 47.2 % in intervention compared to 42.3% in control group.
      • 5.6% of pts from intervention group had clinical signs of a new ischemic CVA in a different area w/in 90 days compared to 0.4% of pts in the control group.
      • Complications in intervention group- embolization into new territory in 8.6%; procedure-related dissection in 1.7%, vessel perforation in 0.9%.
4. Limits:
  • Number of pts in control group > Number of pts in intervention group.
  • Modified TICI score (reperfusion rates) low compared to other studies- 15 pts given a Modified TICI score of 2a à underestimation of reperfusion rates.
  • Patients were aware if treatment group assignments which may have influenced their opinion about their health and functional condition.
  • Broad inclusion criteria à contraindications for IV Alteplase, nonresponse to IV Alteplase, elderly (less recovery potential), pts with extracranial internal-carotid artery occlusions or dissection à all this resulted in a population with poor prognosis.
5. Additional Info:


6. Author: Dr. Nadia Bakor