The A's and B's of the ABC's of stroke mechanisms and recurrence in pediatric ischemic stroke

Arterial ischemic stroke in children is rare, estimated at 2 per 100,000 children per year,¹ but carries a relatively high risk of both recurrent stroke and lifelong neurologic morbidity.² Ischemic stroke mechanisms in both adults and children can be conceptually broken down into the “ABC's”: arterial, blood, and cardiac. The mechanism of the stroke is important as therapeutic decisions and recurrent risk can vary by etiology. Arterial mechanisms (vasculopathies) are among the most common identified risk factors in childhood stroke, and differ dramatically from those seen in adults. They are traditionally divided into inflammatory (e.g., vasculitis, infectious) and noninflammatory (e.g., focal cerebral arteriopathy, moyamoya, dissection) processes. Little is known about the underlying pathophysiology of one of the most common of these vasculopathies, an entity referred to as focal cerebral arteriopathy (FCA). In fact, much controversy exists concerning the definitions and diagnostic criteria for FCA, and how or if these disorders fit into the spectrum of primary CNS angiitis in childhood.³ Complicating matters, over half of pediatric arterial ischemic stroke patients have more than one risk factor.⁴ Novel research strategies have been greatly needed to shed new light on the underlying pathomechanisms of vascular disorders in childhood ischemic stroke.