Abstract
BACKGROUND: The best revascularization strategy for acute ischemic stroke from isolated vertebral artery occlusion remains unclear. METHODS: This retrospective, international, multicenter cohort study included patients from 30 comprehensive stroke centers across Europe (n=23), North America (n=5), and Asia (n=2) between 2016 and 2022. Eligible patients presented with acute ischemic stroke within 24 hours of last seen well and had imaging-confirmed isolated vertebral artery occlusion. Two treatment comparisons were analyzed: intravenous thrombolysis (IVT)-only versus conservative treatment (Cx), and endovascular treatment (EVT)±IVT versus medical management (Cx and IVT). The primary outcome was the shift in 3-month modified Rankin Scale (mRS) score; secondary outcomes included early neurological improvement (24-hour-delta National Institutes of Health Stroke Scale score), recanalization, early neurological deterioration of ischemic origin, symptomatic intracerebral hemorrhage, and 3-month mortality. Analyses were adjusted using inverse probability of treatment weighting (IPTW). RESULTS: Among 494 patients, 143 (29%) received Cx, 218 (44%) IVT-only, and 133 (27%) EVT±IVT. Compared with Cx, IVT-only showed similar 3-month mRS score (IPTW-adjusted odds ratio [aOR] mRS shift score, 1.32 [95% CI, 0.80-2.18]), greater early neurological improvement (IPTW-adjusted-β coefficient, -1 [95% CI, -2.05 to 0.05]), and higher recanalization rates (IPTW-aOR, 4.33 [95% CI, 1.36-13.78]). Compared with MM (=IVT+Cx), EVT±IVT was associated with an unfavorable mRS shift score (IPTW-aOR mRS shift score, 0.51 [95% CI, 0.35-0.74]), higher early neurological deterioration of ischemic origin (IPTW-aOR, 9.06 [95% CI, 2.86-28.67]), and symptomatic intracerebral hemorrhage (IPTW-aOR, 6.05 [95% CI, 1.14-32.1]) though recanalization was over 4-fold higher (OR, 4.64 [95% CI, 1.90-11.33]). Patients with National Institutes of Health Stroke Scale score ≥10 showed point estimates favoring EVT+IVT (P(interaction)=0.025). CONCLUSIONS: IVT-only appeared safe and was associated with better early recovery and recanalization. EVT±IVT showed overall worse outcomes, potentially due to increased early neurological deterioration of ischemic origin and symptomatic intracerebral hemorrhage rates, but may confer benefit in moderate-to-severe strokes, warranting prospective trials in symptomatic isolated vertebral artery occlusion.