Vertebral artery stump syndrome after internal carotid artery stenting: A case report.

RATIONALE: Vertebral artery stump syndrome (VASS) is an uncommon etiology of posterior circulation ischemic stroke. Previous studies have proposed several possible pathogenic mechanisms. However, the precise pathogenesis and initiating factors remain unclear. We present a case of VASS occurring following carotid artery stenting, in which thrombus formation was identified in the vertebral and basilar arteries using black-blood magnetic resonance imaging (MRI). Based on these findings, we propose a plausible pathogenesis and potential triggering factors. PATIENT CONCERNS: We report a case of posterior circulation ischemic stroke following carotid artery stenting, suggesting VASS as the etiology. DIAGNOSES: The diagnosis of VASS was made based on the presence of posterior circulation ischemic stroke, occlusion at the origin of the vertebral artery, antegrade flow in the distal segment of the ipsilateral vertebral artery, and the coexistence of an intracranial arterial occlusion distal to the extracranial lesion, after excluding other potential causes. INTERVENTIONS: We employed a treatment strategy combining antiplatelet and anticoagulant therapy. OUTCOMES: Thrombi were directly visualized in the basilar and vertebral arteries on black-blood MRI, with consistent signal characteristics. The patient's symptoms demonstrated improvement following the implemented treatment regimen. LESSONS: Based on this case, we recommend a comprehensive black-blood MRI evaluation for potential VASS in patients with vertebral artery occlusion prior to performing carotid artery stenting.