Mechanical Thrombectomy for Tandem Vertebrobasilar Stroke: Characteristics and Treatment Outcome

Background and Purpose - Tandem vertebrobasilar strokes are not well-known causes of posterior circulation stroke. The purpose of this study was to investigate the characteristics and outcome of mechanical thrombectomy in patients with tandem vertebrobasilar stroke. Methods - Acute basilar artery occlusion patients with tandem vertebral artery (VA) stenosis/occlusion who underwent mechanical thrombectomy were retrospectively analyzed. Concomitant tandem VA steno-occlusion was defined as severe stenosis/occlusion of the extracranial VA with impaired flow. Clinical/angiographic characteristics, recanalization rate, procedure time, and clinical outcome were evaluated with comparisons according to the treatment strategy. Results - Tandem vertebrobasilar occlusion was identified in 24.6% (55 of 224) of the acute basilar artery occlusion patients. Overall successful recanalization and good clinical outcome was achieved in 87.2% (48 of 55) and 30.9% (17 of 55) of the patients. There were no significant differences in procedure time, recanalization rate, and clinical outcome in comparisons of the VA access route selection or angioplasty of the tandem VA lesion. Two patients developed short-term recurrent basilar artery occlusion when angioplasty of the tandem VA lesion was not performed. Good clinical outcome was more likely with lower baseline National Institutes of Health Stroke Scale score (odds ratio, 0.87 [95% CI, 0.787-0.961]; P=0.006) and short onset-to-recanalization time (odds ratio, 0.993 [95% CI, 0.987-0.999]; P=0.03). Conclusions - Tandem vertebrobasilar occlusion may be a frequent pathological mechanism of posterior circulation stroke. Good outcome may be achieved by strategic choice of the access route and selective angioplasty of the tandem VA lesion.