Endovascular Thrombectomy vs Best Medical Therapy for Late Presentation Acute Ischaemic Stroke with Proximal Large Vessel Occlusion Selected Based on Non-Contrast CT: A Retrospective Analysis of Two Prospectively Defined Cohorts

Singh Dhillon, Permesh; Butt, Waleed; Jovin, Tudor G; Podlasek, Anna; McConachie, Norman; Lenthall, Robert; Nair, Sujit; Malik, Luqman; Krishnan, Kailash; Chiavacci, Iacopo; Mehedi, Farhan; Hong, Timothy; Selva, Harriwin; Dineen, Robert A; England, Timothy J

Abstract

Background: The efficacy and safety of endovascular thrombectomy (EVT) beyond 6 hours from acute ischaemic stroke (AIS) onset for patients selected without CT perfusion or MR imaging is undetermined in routine clinical practice.

Methods: In this single centre study, we identified consecutive late presenting AIS patients who were eligible for EVT based on non-contrast CT/CT angiography (without CT perfusion or MR imaging) using an Alberta Stroke Program Early CT Score (ASPECTS) of ≥6, beyond 6 hours from stroke onset, between January 2018 and March 2022. During the study period, EVT capacity limitations meant EVT-eligible patients presenting out of regular working hours, consistently received best medical management (BMM). Functional outcomes (modified Rankin Scale (mRS) at 90 days), symptomatic intracranial haemorrhage (sICH) and mortality at 90 days were compared between patients receiving EVT or BMM following multivariable adjustment for age, sex, baseline stroke severity, ASPECTS, onset-to-neuroimaging time, IV thrombolysis, and clot location.

Results: Among 4802 AIS patients, 150 patients (3.1%) presenting beyond 6-hours of onset were eligible for EVT: 74 (49%) treated with EVT and 76 (51%) with BMM. Compared to the BMM group, patients treated with EVT had significantly improved functional outcome (mRS) (adjusted common OR=2.23, 95%CI 1.18-4.22, p=0.013), and higher rates of functional independence (mRS≤2; 39.2.% vs 9.2%; aOR=4.73, 95%CI 1.64-13.63, p=0.004). No significant difference was observed between the EVT and BMM groups in the sICH (5.4% vs 2.6%, p=0.94) or mortality (20.2% vs 47.3%, p=0.16) rates, respectively.

Conclusion: In routine clinical practice, of the 3.1% of patients in our AIS population presenting after 6 hours from stroke onset who were deemed eligible for EVT by NCCT/CTA alone, those treated with EVT achieved significantly improved functional outcome, compared to patients treated with BMM only. No significant differences were noted between the two groups with respect to sICH and mortality. While confirmatory randomised trials are awaited, these findings suggest that EVT is effective and safe when performed in AIS patients selected without CTP or MRI beyond 6 hours from stroke onset.

Citation

Singh Dhillon, P., Butt, W., Jovin, T. G., Podlasek, A., McConachie, N., Lenthall, R., …England, T. J. (2023). Endovascular Thrombectomy vs Best Medical Therapy for Late Presentation Acute Ischaemic Stroke with Proximal Large Vessel Occlusion Selected Based on Non-Contrast CT: A Retrospective Analysis of Two Prospectively Defined Cohorts. Stroke: Vascular and Interventional Neurology, 3(2), Article e000686. https://doi.org/10.1161/SVIN.122.000686

• Journal Article Type: Article
• Acceptance Date: Oct 24, 2022
• Online Publication Date: Nov 18, 2022
• Publication Date: 2023-03
• Deposit Date: Oct 28, 2022
• Publicly Available Date: May 19, 2023
• Journal: Stroke: Vascular and Interventional Neurology
• Electronic ISSN: 2694-5746
• Peer Reviewed: Peer Reviewed
• Volume: 3
• Issue: 2
• Article Number: e000686
• DOI: https://doi.org/10.1161/SVIN.122.000686
• Public URL: https://nottingham-repository.worktribe.com/output/12900386
• Publisher URL: https://www.ahajournals.org/doi/full/10.1161/SVIN.122.000686