Relevance of NIHSS subitems for best revascularization therapy in minor stroke patients with large vessel occlusion: an observational multicentric study.

Abstract

The best management of acute ischemic stroke patients with a minor stroke and large vessel occlusion is still uncertain. Specific clinical and radiological data may help to select patients who benefit from Endovascular Therapy (EVT). We aimed to evaluate the relevance of NIHSS subitems for predicting potential benefit of EVT after intravenous thrombolysis (IVT)("bridging treatment") versus IVT alone. We extracted demographic, clinical, risk factor, radiological, revascularization and outcome data from consecutive patients with M1 or proximal M2 middle cerebral artery occlusion and admission NIHSS scores of 0-5 points treated with IVT+/-EVT between May 2005 and March 2021 from nine prospectively-constructed stroke registries from seven French and two Swiss comprehensive stroke centers. Adjusted interaction analyses were performed between admission NIHSS subitems and revascularization modality for two primary outcomes at 3 months: non-excellent functional outcome (mRS 2-6) and difference in NIHSS score between 3 months and admission RESULTS: Of the 533 patients included (median age 68.2 years, 46% women, median admission NIHSS score 3), 136 (25.5%) patients initially received bridging therapy and 397 (74.5%) IVT alone. Adjusted interaction analysis revealed that only facial palsy on admission was more frequently associated with excellent outcome in patients treated by IVT alone versus bridging therapy (OR=0.47, 95%CI=0.24-0.91, p=0.013). Regarding NIHSS-difference at 3 months, no single NIHSS subitems interacted with the type of revascularization. This retrospective multicenter analysis found that NIHSS subitems at admission had little value in predicting patients who might benefit from bridging therapy as opposed to IVT alone. Further research is needed to identify better markers for selecting EVT responders with minor strokes.