Endovascular treatment should be cautiously considered for acute vertebrobasilar artery occlusion patients with National Institutes of Health Stroke Scale score <7.

Abstract

The efficacy of endovascular treatment (EVT) for acute vertebrobasilar artery occlusion (VBAO) with mild severity remains controversial. This study aimed to determine whether a threshold of stroke severity exists at which the efficacy of EVT changes in acute VBAO patients. A retrospective cohort study including patients with acute VBAO from 65 stroke centers in China (December 2015 to June 2022) was conducted. The primary outcome was a 90-day modified Rankin Scale (mRS) score of 0-3. The interaction and visualization analyses were used to clarify the benefits of EVT changes with increasing National Institutes of Health Stroke Scale (NIHSS) score. Multivariable-adjusted logistic regressions were used to validate the intersection point of NIHSS score in the association between treatments and outcomes. Of 4000 acute VBAO patients, 2353 underwent EVT. A significant interaction effect of NIHSS score was observed in the association between treatments and outcomes (P for interaction <0.001), with an intersection point at 6.91. In patients with an NIHSS score <7, EVT combined with best medicine treatment (BMT) was associated with lower mRS 0-3 rates compared with BMT alone (adjusted OR (aOR) 0.63, P=0.031). In contrast, in the patients with an NIHSS score ≥7, the outcome was the opposite (aOR 2.24, P<0.001). EVT should be cautiously considered in acute VBAO patients with an NIHSS score <7. Decisions require weighing baseline function, imaging features, and vascular anatomy. In the future, predictive models for EVT may enable more precise patient selection.