Case Report: Successful Anterior Circulation Thrombectomy After 24 Hours in an Adolescent.

BACKGROUND: Arterial ischemic stroke in children comes with the potential for morbidity and mortality and can result in high cost of care and decreased quality of life among survivors. Children with arterial ischemic stroke are increasingly being treated with mechanical thrombectomy, but little is known about the risks and benefits 24 hours after a patient's last known well (LKW) time. METHODS: A 16-year-old female presented with acute onset of dysarthria and right hemiparesis with LKW time 22 hours prior. Pediatric National Institutes of Health Stroke Scale score was 12. Magnetic resonance imaging showed diffusion restriction and T2 hyperintensity primarily in the left basal ganglia. Magnetic resonance angiography revealed left M1 occlusion. Arterial spin labeling showed a large apparent perfusion deficit. She underwent thrombectomy with TICI3 recanalization 29.5 hours after LKW time. RESULTS: At 2-month follow-up, her examination showed moderate right-hand weakness and mild diminished sensation of the right arm. CONCLUSIONS: Adult thrombectomy trials include patients up to 24 hours from their LKW time and suggest that some patients maintain a favorable perfusion profile for over 24 hours. Without intervention many go on to experience infarct expansion. The persistence of a favorable perfusion profile likely reflects robust collateral circulation. We hypothesized our patient was relying on collateral circulation to maintain the noninfarcted areas of her left middle cerebral artery territory. Owing to concern for eventual collateral failure, thrombectomy outside of the 24-hour window was performed. This case serves as a call to action to better understand the impact of collateral circulation on cerebral perfusion in children with large vessel occlusions and delineate which children may benefit from thrombectomy in a delayed time window.

Stroke Caused by Arterial Thoracic Outlet Syndrome in an Adolescent.

Arterial thoracic outlet syndrome is a rare condition characterized by compression of the subclavian artery, often with post-stenotic aneurysm formation. Artery-to-artery embolic strokes related to thoracic outlet syndrome have been reported in the posterior circulation and in the ipsilateral anterior circulation. We present a case in which a thrombus secondary to thoracic outlet syndrome caused a contralateral anterior circulation stroke in an adolescent and postulate mechanisms of this rare occurrence. This case demonstrates that a subclavian thrombus due to thoracic outlet syndrome can take a circuitous path and cause an anterior circulation stroke contralateral to the diseased subclavian artery. In addition, this case illustrates the importance of a high index of suspicion for thoracic outlet syndrome in patients with stroke and associated arm pain or discoloration.