Introduction: Endovascular therapy(EVT) is proven effective for patients with acute ischemic stroke with proximal vessel occlusion, treated within 6 hours since symptom onset. However, up to 30% of stroke patients wake up with their symptoms (“wake-up stroke” (WUS)) or have an unknown time of onset. Canadian guidelines suggest that EVT may also be effective up to 12 hours after onset and yet-to-be published data from the DAWN trial also suggest a strong benefit of EVT for these patients if selected by perfusion imaging. We aimed to examine the real-world effectiveness of EVT in late-presenting stroke patients selected for EVT with a simple non-contrast CT (NCCT) and simple phase CT angiogram (CTA).
Methods: We analyzed a prospectively collected registry of epidemiological, clinical and imaging data of patients treated for acute ischemic stroke ≥6 hours since symptom onset or WUS in a tertiary stroke center (Hôpital Notre-Dame, Montréal) between 2016 and 2017. Eligibility for EVT was based on a combination of disabling neurological deficit, a NCCT with salvageable brain tissue (ASPECTS >5), and presence of a LVO on CTA.
Results: Over a 16-month period, a total of 366 patients were treated with IV thrombolysis and/or EVT. Of these, 46 had WUS or presented ≥ 6 hours since symptom onset and received EVT. Median age was 70, median baseline mRS score 1, median NIHSS at arrival 17 and median ASPECTS 9. Good collaterals on CTA were noted in 63%(29) of patients. 5 patients had posterior circulation stroke with basilar occlusion. Median time from last time seen normal to admission was 9h17(IQR, 6h44-12h46). 31 (67.4%) NCCTs were done at a referent center and not repeated locally to avoid treatment delays. At 3-month follow-up, functional autonomy(mRS≤2) was found in 15 (32.6%) patients while 15 (32,6%) died (mRS=6). Symptomatic hemorrhagic transformation occurred in 3(6.5%) patients.
Conclusions: In a real-world setting, EVT is feasible in late-presenting stroke patients selected by NCCT and yields favorable outcomes similar to those seen in the more pragmatic EVT trials.