Background and Purpose: To find out if the beneficial effect of endovascular treatment (EVT) on functional outcome could be explained by a reduction in post treatment infarct volume in the REVASCAT multi-center randomized controlled trial.
Methods: The REVASCAT trial was a multicenter randomized open-label trial with blinded outcome evaluation. Among 206 enrolled subjects (EVT n=103; control n=103), post treatment infarct volume was measured in 204 subjects. Post treatment infarct volumes were compared by treatment assignment and recanalization status. Appropriate statistical models were used to assess relationship between baseline clinical and imaging variables, post treatment infarct volume and functional status at 90 days [modified Rankin Scale (mRS)].
Results: Median post treatment infarct volume in all subjects was 23.7 ml (IQR 9.3-78.2 ml), in the EVT arm (16.3 ml, IQR 8.3-58.5 ml) and in the control arm (38.6 ml, IQR 11.9-86.8 ml) (p<0.02). Median post treatment infarct volume in the EVT arm in recanalizers was 14.6 ml (IQR 7.8-46.2 ml) vs. 92.9 ml (IQR 14.6-233.1 ml) in the non-recanalizers (p=0.05). Median post treatment infarct volume in the control arm in recanalizers was 18.1 ml (IQR 8.4-76.7 ml) vs. 92.9 ml (IQR 14.6-233.1 ml) in the non-recanalizers (p=0.02). Post treatment infarct volume (p<0.001) and recanalization status (p<0.01) were the only independent predictors of 90 day mRS; all baseline variables lost their relevance in this model.
Conclusion: Endovascular therapy in the REVASCAT trial was associated with a significant reduction in infarct volume. Recanalization status and post treatment infarct volume best predict 90-day clinical outcomes.