Reflux of Anterior Spinal Artery Predicts Recurrent Posterior Circulation Stroke in Bilateral Vertebral Artery Disease.

BACKGROUNDS AND PURPOSE Predictive value of reflux of anterior spinal artery for recurrent posterior circulation ischemia in bilateral vertebral arteries steno-occlusive disease was evaluated. METHODS We retrospectively reviewed 55 patients with symptomatic posterior circulation stroke caused by bilateral stenotic (>70%) lesions of the vertebral artery. We investigated any correlation of clinical and angiographic characteristics including collateral flow patterns, with recurrent stroke. Risk factors for poor 3-month functional outcome were also evaluated. RESULTS Recurrent posterior circulation stroke was observed in 15 (27.3%) patients. Multivariable analysis using Cox proportional hazards model showed anterior spinal artery reflux as a significant risk factor for stroke recurrence (adjusted hazard ratio, 19.3 [95% confidence interval, 5.35-69.9]; P<0.001). Anterior spinal artery reflux was also correlated with poor functional outcome (modified Rankin Scale score, 3-6; adjusted odds ratio, 7.41 [95% confidence interval, 1.24-44.4]; P=0.028). CONCLUSIONS In patients with symptomatic bilateral vertebral artery occlusive disease, anterior spinal artery reflux predicted recurrent posterior circulation stroke and poor functional outcome.