Abstract
Objectives
The beneficial effect of endovascular thrombectomy (EVT) on clinical outcome is assumed
to be caused by reduced follow-up infarct volume (FIV), which could serve as an early
imaging endpoint. However, the effect of EVT on the modified Rankin Scale (mRS) was
poorly explained by FIV. NIHSS at 5-7 days could be a more specific measure of the
effect of reperfusion therapy, as opposed to the mRS at 3 months. Therefore, we aimed
to assess to what extent the effect of EVT on NIHSS is explained by FIV.
Materials and methods
We used data from the MR CLEAN (Multicenter Randomized Clinical Trial of Endovascular
Treatment for Acute Ischemic Stroke in the Netherlands; n = 500) trial to evaluate the mediating role of FIV within 1 week in the relationship
between EVT and baseline adjusted NIHSS at 5–7 days.
Results
Larger FIVs were associated with higher NIHSS after treatment (adjusted beta-coefficient
(aβ) 0.47;95%CI 0.39-0.55). EVT was associated with smaller FIVs (β -0.35;95%CI-0.64
to -0.06) and lower NIHSS (β -0.63;95%CI-0.90 to -0.35). After adjustment for FIV,
the effect of EVT on NIHSS decreased (aβ -0.47;95%CI-0.72 to -0.23), indicating that
effect of EVT on neurologic deficit is partially mediated by FIV. Reduction of FIV
explained 34% (95%CI;5%–93%) of the effect of EVT on the NIHSS at 5–7 days.
Conclusions
Larger FIV was significantly associated with larger neurological deficits after treatment.
Reduced infarct volume after EVT explains one third of treatment benefit in terms
of neurological deficit. This suggests that FIV is of interest as an imaging biomarker
of stroke treatment effect.
Keywords
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Article info
Publication history
Published online: December 04, 2022
Accepted:
November 20,
2022
Received:
August 25,
2022
Identification
DOI: https://doi.org/10.1016/j.jstrokecerebrovasdis.2022.106906
Copyright
© 2022 Published by Elsevier Inc.
