Abstract Body: BACKGROUND
We aimed to estimate the effect of endovascular therapy (EVT) in addition to best medical treatment (BMT) compared to BMT alone on the volume of brain tissue that was saved after an acute ischemic stroke (AIS) due to a medium distal vessel occlusion (MDVO).
HYPOTHESIS
We assessed the hypothesis that EVT in addition to BMT compared to BMT alone leads to a bigger volume of saved brain tissue in AIS patient with a MDVO.
METHODS
We based our analysis on the data collected from the DISTAL Trial (ClinicalTrials.gov Identifier: NCT05029414), an investigator-initiated, open-label, multicenter, randomized, two-arm, assessor-blinded trial at 61 sites in 11 countries with the goal to randomly assign 543 eligible participants in a 1:1 ratio to EVT plus BMT or BMT alone. Eligible patients had an isolated occlusion of either the co- or non-dominant M2 segment, the M3 or M4 segment of the middle cerebral artery, the A1, A2 or A3 segment of the anterior cerebral artery or the P1, P2 or P3 segment of the posterior cerebral artery that was confirmed on non-invasive vessel imaging and that could be treated within 24 hours of symptom onset.
In this sub-analysis we used the available imaging data of those patients. We included only patients with baseline perfusion imaging (CT or MRI) and available follow-up imaging (CT or MRI within the first 24 hours). We compared the affected volume of brain tissue in ml at baseline, assessed using the the tissue at risk on perfusion, and follow-up imaging, assessed by the demarcation on CT or FLAIR MRI sequence. Specifically, we measured the volume of the penumbra defined by Tmax thresholds at baseline and segmented the demarcation of the infarct volume at follow-up through manual or algorithmic methods. The segmentations were made from a blinded resident neuroradiologist and were corrected from a second experienced neuroradiologist.
The primary endpoint was the difference of tissue at risk and final infarct. ΔVol (ml) = Volume of the tissue at risk (Baseline perfusion) - Volume of the demarcation (24h follow-up). As a secondary analysis we will test the hypothesis that the ΔV in patients with NIHSS > 5 in the EVT + BMT group is bigger from that from the BMT alone group.
RESULTS
A total of 543 patients (44% female, mean age 74.8 years) were assigned to either EVT plus BMT (N=271) or the control group (N=272). The results will be available at ISC 2025.
CONCLUSION
Results will be available at ISC 2025.