Triage of Patients Presenting Beyond 24 Hours From Last Known Well With Acute Ischemic Stroke Due to Large Vessel Occlusions (TRACK-LVO Late): a TRACK-LVO Registry-linked Cohort

There is an abundance of evidence demonstrating the efficacy and safety of endovascular therapy (EVT) within 24 hours of stroke onset. However, the potential benefits of EVT beyond this time window remain uncertain. To address this knowledge gap, the investigators established a TRACK-LVO Late linked cohort, specifically designed to investigate the outcomes of EVT in patients with LVO presenting beyond 24 hours from last known well.

This cohort includes patients from the TRACK-LVO registry who received either EVT or best medical treatment (BMT) beyond 24 hours from symptom onset. The cohort focuses on patients with LVO in the anterior circulation, confirmed by magnetic resonance angiography (MRA), computed tomography angiography (CTA), or digital subtraction angiography (DSA) in the EVT group. To maximize the sample size in the BMT group, the investigators also included patients with LVO confirmed using transcranial Doppler and carotid ultrasonography, in addition to the aforementioned imaging modalities.

Consistent with the TRACK-LVO registry, LVO is defined as an occlusion of the intracranial internal carotid artery (ICA) , M1 and/or M2 segments of the middle cerebral artery (MCA), A1 and/or A2 segments of the anterior cerebral artery (ACA), any segments of vertebral artery (VA), basilar artery (BA), or P1 and/or P2 segments of the posterior cerebral artery (PCA).

The investigators collect comprehensive patient information, including baseline demographic profiles, imaging characteristics such as ischemic core volume and FVH-DWI mismatch, CT/MR perfusion parameters, and treatment-related complications, for both EVT and BMT groups. For patients in the EVT group, the investigators also obtained detailed information on the EVT procedure and angiographic images.

By establishing this cohort, the investigators aim to provide high-level evidence to guide the treatment of a subgroup of stroke patients who present beyond the current guideline-recommended time window for EVT. The findings will contribute to determining the superiority of EVT over BMT in ischemic stroke patients with LVO and extended time from symptom onset.