Clinical and Radiological Recurrence After Childhood Arterial Ischemic Stroke

Pediatric Moyamoya Revascularization Perioperative Care: A Modified Delphi Study

BACKGROUND

Surgical revascularization decreases the long-term risk of stroke in children with moyamoya arteriopathy but can be associated with an increased risk of stroke during the perioperative period. Evidence-based approaches to optimize perioperative management are limited and practice varies widely. Using a modified Delphi process, we sought to establish expert consensus on key components of the perioperative care of children with moyamoya undergoing indirect revascularization surgery and identify areas of equipoise to define future research priorities.

METHODS

Thirty neurologists, neurosurgeons, and intensivists practicing in North America with expertise in the management of pediatric moyamoya were invited to participate in a three-round, modified Delphi process consisting of a 138-item practice patterns survey, anonymous electronic evaluation of 88 consensus statements on a 5-point Likert scale, and a virtual group meeting during which statements were discussed, revised, and reassessed. Consensus was defined as ≥ 80% agreement or disagreement.

RESULTS

Thirty-nine statements regarding perioperative pediatric moyamoya care for indirect revascularization surgery reached consensus. Salient areas of consensus included the following: (1) children at a high risk for stroke and those with sickle cell disease should be preadmitted prior to indirect revascularization; (2) intravenous isotonic fluids should be administered in all patients for at least 4 h before and 24 h after surgery; (3) aspirin should not be discontinued in the immediate preoperative and postoperative periods; (4) arterial lines for blood pressure monitoring should be continued for at least 24 h after surgery and until active interventions to achieve blood pressure goals are not needed; (5) postoperative care should include hourly vital signs for at least 24 h, hourly neurologic assessments for at least 12 h, adequate pain control, maintaining normoxia and normothermia, and avoiding hypotension; and (6) intravenous fluid bolus administration should be considered the first-line intervention for new focal neurologic deficits following indirect revascularization surgery.

CONCLUSIONS

In the absence of data supporting specific care practices before and after indirect revascularization surgery in children with moyamoya, this Delphi process defined areas of consensus among neurosurgeons, neurologists, and intensivists with moyamoya expertise. Research priorities identified include determining the role of continuous electroencephalography in postoperative moyamoya care, optimal perioperative blood pressure and hemoglobin targets, and the role of supplemental oxygen for treatment of suspected postoperative ischemia.

Transcranial Doppler in Childhood Moyamoya: An Underutilized Tool?

BACKGROUND

Children with moyamoya are at high risk for incident and recurrent stroke. Transcranial Doppler (TCD) ultrasound is an attractive option to screen high-risk populations for moyamoya and to provide stroke risk stratification information due to its safety and cost-effectiveness. We used TCD to evaluate cerebral blood flow velocities in children with presurgical moyamoya and to determine if velocities differ between children with stable and unstable disease.

METHODS

Fourteen participants aged ≤21 years with a radiographic diagnosis of moyamoya or moyamoya-like arteriopathy underwent a research TCD at a median age of 7.2 years. TCDs were performed outside of the setting of acute stroke and before surgical revascularization. Arteriopathy was classified as unstable if the participant had a stroke or transient ischemic attack within three months preceding the TCD.

RESULTS

Middle cerebral artery and internal carotid artery (ICA) blood flow velocities were elevated. The median M1 velocity was 138 cm/s (interquartile range [IQR] 106 to 168). Individual M1 flow velocities were a median of 5.0 S.D.s above age-based normative values. The median distal ICA velocity was 146 cm/s (IQR 124 to 163). Individual ICA flow velocities were a median of 5.9 S.D.s above normative values. Participants with unstable arteriopathy had higher M1 velocities compared with those with stable arteriopathy (170 vs 119 cm/s, P = 0.0003). We did not identify velocity differences based on comorbid conditions or age.

CONCLUSIONS

These preliminary data suggest that TCD is a promising tool for screening for cerebral arteriopathies in high-risk pediatric populations and assessment for unstable disease.

Immune-Neurovascular Interactions in Experimental Perinatal and Childhood Arterial Ischemic Stroke

Emerging clinical and preclinical data have demonstrated that the pathophysiology of arterial ischemic stroke in the adult, neonates, and children share similar mechanisms that regulate brain damage but also have distinct molecular signatures and involved cellular pathways due to the maturational stage of the central nervous system and the immune system at the time of the insult. In this review, we discuss similarities and differences identified thus far in rodent models of 2 different diseases-neonatal (perinatal) and childhood arterial ischemic stroke. In particular, we review acquired knowledge of the role of resident and peripheral immune populations in modulating outcomes in models of perinatal and childhood arterial ischemic stroke and the most recent and relevant findings in relation to the immune-neurovascular crosstalk, and how the influence of inflammatory mediators is dependent on specific brain maturation stages. Finally, we discuss the current state of treatments geared toward age-appropriate therapies that signal via the immune-neurovascular interaction and consider sex differences to achieve successful translation.

The Progression of Pathophysiology of Moyamoya Disease

Moyamoya disease (MMD) is a chronic steno-occlusive cerebrovascular disease that often leads to hemorrhagic and ischemic strokes; however, its etiology remains elusive. Surgical revascularization by either direct or indirect bypass techniques to restore cerebral hypoperfusion is the treatment of choice to date. This review aims to provide an overview of the current advances in the pathophysiology of MMD, including the genetic, angiogenic, and inflammatory factors related to disease progression. These factors may cause MMD-related vascular stenosis and aberrant angiogenesis in complex manners. With a better understanding of the pathophysiology of MMD, nonsurgical approaches that target the pathogenesis of MMD may be able to halt or slow the progression of this disease.

Risk Factors for Preoperative Cerebral Infarction in Infants with Moyamoya Disease

There have been few reports on the risk factors for preoperative cerebral infarction in childhood moyamoya disease (MMD) in infants under 4 years. The aim of this retrospective study is to identify clinical and radiological risk factors for preoperative cerebral infarction in infants under 4 years old with MMD, and the optimal timing for EDAS was also considered. We retrospectively analyzed the risk factors for preoperative cerebral infarction, confirmed by magnetic resonance angiography (MRA), in pediatric patients aged ˂4 years who underwent encephaloduroarteriosynangiosis between April 2005 and July 2022. The clinical and radiological outcomes were determined by two independent reviewers. In addition, potential risk factors for preoperative cerebral infarction, including infarctions at diagnosis and while awaiting surgery, were analyzed using a univariate model and multivariate logistic regression to identify independent predictors of preoperative cerebral infarction. A total of 160 hemispheres from 83 patients aged <4 years with MMD were included in this study. The mean age of all surgical hemispheres at diagnosis was 2.17±0.831 years (range 0.380-3.81 years). In the multivariate logistic regression model, we included all variables with P<0.1 in the univariate analysis. The multivariate logistic regression analysis indicated that preoperative MRA grade (odds ratio [OR], 2.05 [95% confidence interval [CI], 1.3-3.25], P=0. 002), and age at diagnosis (OR, 0.61 [95% CI, 0.4-0.92], P=0. 018) were predictive factors of infarction at diagnosis. The analysis further indicated that the onset of infarction (OR, 0.01 [95% CI, 0-0.08], P<0.001), preoperative MRA grade (OR, 1.7 [95% CI, 1.03-2.8], P=0.037), and duration from diagnosis to surgery (Diag-Op) (OR, 1.25 [95% CI, 1.11-1.41], P<0.001) were predictive factors for infarction while awaiting surgery. Moreover, the regression analysis indicated that family history (OR, 8.88 [95% CI, 0.91-86.83], P=0.06), preoperative MRA grade (OR, 8.72 [95% CI, 3.44-22.07], P<0.001), age at diagnosis (OR, 0.36 [95% CI, 0.14-0.91], P=0.031), and Diag-Op (OR, 1.38 [95% CI, 1.14-1.67], P=0.001) were predictive factors for total infarction. Therefore, during the entire treatment process, careful observation, adequate risk factor management, and optimal operation time are required to prevent preoperative cerebral infarction, particularly in pediatric patients with a family history, higher preoperative MRA grade, duration from diagnosis to operation longer than 3.53 months, and aged ˂3 years at diagnosis.

Management of Pediatric Stroke - Challenges and Perspectives from Resource-limited Settings

Childhood stroke is not as common as adult stroke, but it is underrecognized the world over. Diagnosis is often delayed due to lack of awareness not only by the lay public but also by emergency and front-line health care workers. Despite the relative rarity of childhood stroke, the impact on morbidity, mortality and the economic burden for families and society is high, especially in poorly resourced settings. The risk factors for stroke in children differ from the adult population where lifestyle factors play a more important role. The developmental aspects of the pediatric cerebral vasculature and hematological maturational biology affects the clinical presentation, investigation, management and outcomes of childhood stroke in a different way compared to adults. The management of childhood stroke is currently based on expert guidelines and evidence extrapolated from adult studies. Hyperacute therapies that have revolutionized the treatment of stroke in adults cannot be easily applied to children at this stage due to the diagnostic delays, diverse risk factors and developmental considerations mentioned above. Much has been achieved in the understanding of genetic, acquired, preventable and recurrent stroke risk factors in the past decade through international collaborative efforts like the International Pediatric Stroke Study. Evidence for the prevention and treatment of childhood stroke remains elusive. Even more elusive are relevant and achievable management guidelines for pediatric stroke in resource-limited settings. This narrative review focusses on the current management practices globally, emphasizing the challenges, and gaps in knowledge of pediatric stroke in low- and middle-income countries and other areas with limited resources. Priorities and some potential solutions at national and local level are suggested for these settings.

Viral mimetic triggers cerebral arteriopathy in juvenile brain via neutrophil elastase and NETosis

Stroke is among the top ten causes of death in children but has received disproportionally little attention. Cerebral arteriopathies account for up to 80% of childhood arterial ischemic stroke (CAIS) cases and are strongly predictive of CAIS recurrence and poorer outcomes. The underlying mechanisms of sensitization of neurovasculature by viral infection are undefined. In the first age-appropriate model for childhood arteriopathy-by administration of viral mimetic TLR3-agonist Polyinosinic:polycytidylic acid (Poly-IC) in juvenile mice-we identified a key role of the TLR3-neutrophil axis in disrupting the structural-functional integrity of the blood-brain barrier (BBB) and distorting the developing neurovascular architecture and vascular networks. First, using an array of in-vivo/post-vivo vascular imaging, genetic, enzymatic and pharmacological approaches, we report marked Poly-IC-mediated extravascular leakage of albumin (66kDa) and of a small molecule DiI (∼934Da) and disrupted tight junctions. Poly-IC also enhanced the neuroinflammatory milieu, promoted neutrophil recruitment, profoundly upregulated neutrophil elastase (NE), and induced neutrophil extracellular trap formation (NETosis). Finally, we show that functional BBB disturbances, NETosis and neuroinflammation are markedly attenuated by pharmacological inhibition of NE (Sivelestat). Altogether, these data reveal NE/NETosis as a novel therapeutic target for viral-induced cerebral arteriopathies in children.

Epidemiology of Stroke in Sickle Cell Disease

Sickle cell disease is the most common cause of stroke in childhood, both ischaemic and haemorrhagic, and it also affects adults with the condition. Without any screening or preventative treatment, the incidence appears to fall within the range 0.5 to 0.9 per 100 patient years of observation. Newborn screening with Penicillin prophylaxis and vaccination leading to reduced bacterial infection may have reduced the incidence, alongside increasing hydroxyurea prescription. Transcranial Doppler screening and prophylactic chronic transfusion for at least an initial year has reduced the incidence of stroke by up to 10-fold in children with time averaged mean of the maximum velocity >200 cm/s. Hydroxyurea also appears to reduce the incidence of first stroke to a similar extent in the same group but the optimal dose remains controversial. The prevention of haemorrhagic stroke at all ages and ischaemic stroke in adults has not yet received the same degree of attention. Although there are fewer studies, silent cerebral infarction on magnetic resonance imaging (MRI), and other neurological conditions, including headache, epilepsy and cognitive dysfunction, are also more prevalent in sickle cell disease compared with age matched controls. Clinical, neuropsychological and quantitative MRI screening may prove useful for understanding epidemiology and aetiology.

Microglia-leucocyte axis in cerebral ischaemia and inflammation in the developing brain

Development of the Central Nervous System (CNS) is reliant on the proper function of numerous intricately orchestrated mechanisms that mature independently, including constant communication between the CNS and the peripheral immune system. This review summarizes experimental knowledge of how cerebral ischaemia in infants and children alters physiological communication between leucocytes, brain immune cells, microglia and the neurovascular unit (NVU)-the "microglia-leucocyte axis"-and contributes to acute and long-term brain injury. We outline physiological development of CNS barriers in relation to microglial and leucocyte maturation and the plethora of mechanisms by which microglia and peripheral leucocytes communicate during postnatal period, including receptor-mediated and intracellular inflammatory signalling, lipids, soluble factors and extracellular vesicles. We focus on the "microglia-leucocyte axis" in rodent models of most common ischaemic brain diseases in the at-term infants, hypoxic-ischaemic encephalopathy (HIE) and focal arterial stroke and discuss commonalities and distinctions of immune-neurovascular mechanisms in neonatal and childhood stroke compared to stroke in adults. Given that hypoxic and ischaemic brain damage involve Toll-like receptor (TLR) activation, we discuss the modulatory role of viral and bacterial TLR2/3/4-mediated infection in HIE, perinatal and childhood stroke. Furthermore, we provide perspective of the dynamics and contribution of the axis in cerebral ischaemia depending on the CNS maturational stage at the time of insult, and modulation independently and in consort by individual axis components and in a sex dependent ways. Improved understanding on how to modify crosstalk between microglia and leucocytes will aid in developing age-appropriate therapies for infants and children who suffered cerebral ischaemia.

Thrombectomy in special populations: report of the Society of NeuroInterventional Surgery Standards and Guidelines Committee

BACKGROUND

The purpose of this guideline is to summarize the data available for performing mechanical thrombectomy (MT) for emergent large vessel occlusion (ELVO) stroke in special populations not typically included in large randomized controlled clinical trials, including children, the elderly, pregnant women, patients who have recently undergone surgery, and patients with thrombocytopenia, collagen vascular disorders, and endocarditis.

METHODS

We performed a literature review for studies examining the indications, efficacy, and outcomes for patients undergoing MT for ischemic stroke aged <18 years and >80 years, pregnant patients, patients who have recently undergone surgery, and those with thrombocytopenia, collagen vascular diseases, or endocarditis. We graded the quality of the evidence.

RESULTS

MT can be effective for the treatment of ELVO in ischemic stroke for patients over age 80 years and under age 18 years, thrombocytopenic patients, pregnant patients, and patients with endocarditis. While outcomes are worse compared to younger patients and those with normal platelet counts (respectively), there is still a benefit in the elderly (in both mRS and mortality). Data are very limited for patients with collagen vascular diseases; although diagnostic cerebral angiography carries increased risks, MT may be appropriate in carefully selected patients in whom untreated ELVO would likely result in disabling or fatal outcome.

Early Deaths after Arterial Ischemic Stroke in Pediatric Patients: Incidence and Risk Factors

In developed countries, cerebrovascular diseases are among the 10 most common causes of death in both the pediatric and adult population. The prevalence of fatal outcomes following arterial ischemic stroke (AIS) in various groups of pediatric patients ranges from 1% to almost 32%. However, a constant improvement in stroke mortality among children has been observed. The extent of the decline differs among studies (from nearly tenfold to twofold decline), as it depends on the study population. While a portion of this variability might be explained by factors such as health care access, population age, diseases related to ethnicity, and different etiologies of stroke in studied populations, the understanding of such differences is still insufficient. Risk factors for death in the early stages of the disease are poorly understood and are usually based on the clinical presentations of relatively small groups of pediatric patients. Familiarity with these factors may be of significant importance for prognosis, but also for the early selection of patients requiring careful supervision. The present study aimed to analyze and discuss the current literature data on the incidence of early death and risk factors for early death in children suffering from stroke.

Hypertension and childhood stroke

Cerebrovascular disease (stroke) is one of the ten leading causes of death in children and adolescents. Multiple etiologies, from arteriopathies to prothrombic states, can cause stroke in youth. In adult stroke, hypertension has been shown to be the single most important modifiable risk factor. Although hypertension has not been strongly identified as a risk factor in childhood stroke to date, there is preliminary evidence that suggests that hypertension may also be associated with stroke in children. In this review, we summarize the literature that may link hypertension to stroke in the young. We have identified a series of barriers and limitations in the fields of pediatric hypertension and pediatric neurology that might explain why hypertension has been overlooked in childhood stroke. We suggest that hypertension may be a relevant risk factor that, alone or in combination with other multiple factors, contributes to the development of stroke in children. Currently, there are no consensus guidelines for the management of post-stroke hypertension in children. Thus, we recommend that blood pressure be assessed carefully in every child presenting with acute stroke in order to better understand the effects of hypertension in the development and the outcome of childhood stroke. We suggest a treatment algorithm to help practitioners manage hypertension after a stroke.

Clinical Perspective on Primary Angiitis of the Central Nervous System in Childhood (cPACNS)

Non-arteriosclerotic arteriopathies have emerged as important underlying pathomechanism in pediatric arterial ischemic stroke (AIS). The pathogenesis and classification of cerebral arteriopathies in childhood are heterogeneous. Different classifications base on (i) the anatomic site; (ii) the distribution and size of the affected vessel; (iii) the time course, for example, transient vs. progressive, monophasic vs. recurrent; (iv) the putative pathogenesis; (v) the magnetic resonance imaging morphology of the vasculopathies. Inflammation affecting the cerebral vessels is increasingly recognized as common cause of pediatric AIS. Primary cerebral vasculitis or primary angiitis of the central nervous system (CNS) in childhood (cPACNS) is an important differential diagnosis in pediatric AIS. Primary angiitis of the CNS is a rare disorder, and the pathogenesis is poorly understood so far. The current classification of cPACNS is based on the affected cerebral vessel size, the disease course, and angiographic pattern. Two large subtypes are currently recognized comprising large- and medium-sized vessel CNS vasculitis referred to as angiography-positive cPACNS and angiography-negative small vessel cPACNS. As the clinical manifestations of cPACNS are rather diverse, precise diagnosis can be challenging for the treating pediatrician because of the lack of vital laboratory tests or imaging features. Initial misdiagnosis is common because of overlapping phenotypes and pediatric AIS mimics. As untreated cPACNS is associated with a high morbidity and mortality, timely diagnosis, and induction of immunomodulatory and symptomatic therapy are essential. Survival and neurological outcome depend on early diagnosis and prompt therapy. Primary angiitis of the central nervous system in childhood differs in several aspects from primary cerebral angiitis in adults. The aim of this article is to give a brief comprehensive summary on pediatric primary cerebral vasculitis focusing on the clinical perspective regarding the classification, the putative pathogenesis, the disease course, the diagnostic tools, and emerging treatment options. A modified terminology for clinical practice is discussed.

Pediatric Stroke: A Single-Center Experience

The aim of this study was to evaluate the clinical characteristics, risk factors, treatment, and outcomes of pediatric stroke cases. A total of 118 patients diagnosed with arterial ischemic stroke (AIS), hemorrhagic stroke, and sinovenous thrombosis (SVT) between January 2000 and December 2011 were included. Neonatal cases were excluded. Demographic and clinical findings were retrospectively examined from medical records. We identified 118 patients with stroke. The age of the patients ranged from 1 to 215 months (17.92 y), with a mean age of 5.19±5.25 years. AIS accounted for the majority of cases (n=69, 58.5%), and the major etiology was cardiac disease (17%). Hemorrhagic stroke accounted for 19.5% (n=23) of the cases, and late hemorrhagic disease of the newborn was the major etiology (43%, n=10). SVT accounted for 22% (n=26) of the cases, and the major etiology was otitis media-mastoiditis (27%, n=7). Hemiplegia and headache were the most frequent symptoms for AIS and SVT, respectively. Stroke is rare in children compared with adults; however, it is detected more frequently with better imaging techniques and increased awareness. We found that children with AIS presented more commonly with hemiplegia and children with SVT with headache and strabismus. We did not find an association between thrombophilia and stroke.

CX3CR1-CCR2-dependent monocyte-microglial signaling modulates neurovascular leakage and acute injury in a mouse model of childhood stroke

Stroke is among the top 10 causes of death in children. The developmental stage of the brain is central to stroke pathophysiology. The incidence of childhood arterial ischemic stroke (CAIS) is lower than of perinatal arterial ischemic stroke but the rate of recurrence is strikingly high. Vascular inflammation is seen as major contributor to CAIS but the mechanisms that govern structural-functional basis of vascular abnormalities remain poorly understood. To identify the contribution of immune-neurovascular interactions to CAIS, we established stroke model in postnatal day 21 (P21) mice. We demonstrate acute functional deficits and histological injury and chronic MRI-identifiable injury, brain atrophy and marked derangements in the vascular network. In contrast to negligible albumin leakage and neutrophil infiltration following acute perinatal stroke, CAIS leads to significantly increased albumin leakage and neutrophil infiltration in injured regions of wild type mice and mice with functional CX3CR1-CCR2 receptors. In mice with dysfunctional CX3CR1-CCR2 signaling, extravascular albumin leakage is significantly attenuated, infiltration of injurious Ccr2⁺-monocytes essentially aborted, accumulation of Ly6G+ neutrophils reduced and acute injury attenuated. Unique identifiers of microglia and monocytes revealed phenotypic changes in each cell subtype of the monocyte lineage after CAIS. Taken together, CX3CR1-CCR2-dependent microglia-monocyte signaling contributes to cerebrovascular leakage, inflammation and CAIS injury.

Language and cognitive outcomes after childhood stroke: Theoretical implications for hemispheric specialization

The purpose of this study was to investigate language and cognitive outcomes following severe childhood stroke, and the role of age at stroke according to lesion lateralization. We retrospectively included children consecutively admitted to a physical medicine and rehabilitation department between 1992 and 2015 following childhood stroke (age at stroke 1 month to15 years). Data collection included demographic and clinical information, results of cognitive assessments on the Wechsler Intelligence scales, detailed language assessments by speech and language therapists, and long-term academic outcome. Overall, 184 children (52% boys; mean age at assessment = 8.5 years, range .7-15.4 years) were hospitalized following ischemic (n = 79) or hemorrhagic (n = 105) stroke. After a median time since stroke of 4 months (n = 135), mean Full-Scale, Verbal, and Performance Intellectual Quotient (FSIQ, VIQ and PIQ) were 85 (SD = 19), 93 (SD = 22), and 85 (SD = 20), respectively. In language tests (n = 130) assessing lexical and syntactic expression and comprehension, 26%-53% of the children exhibited impairments (scores <2SD). After a median follow-up of 40 months, only 27% of the children were following a normal curriculum without adaptations or delay, and 27% were attending special education programs. School situation was strongly associated with language and FSIQ scores. Language and verbal IQ scores were significantly lower (p < .01) among patients with lesions in the left hemisphere as opposed to the right. After a left hemisphere lesion, language skills were not associated with age at stroke, but for right hemisphere lesions, language was more impaired among children who were younger at stroke onset. PIQ tended to correlate positively with age at stroke in left hemisphere lesions (poorer PIQ in early lesions) and negatively for right hemisphere lesions (poorer PIQ in late lesions). These findings, discussed in the light of the brain vulnerability and plasticity hypotheses, are in favor of a developmental view of hemispheric specialization.

Features of Childhood Arterial Ischemic Stroke in China

Objective: The aim of this study was to identify the features and risk factors for arterial ischemic stroke (AIS) in children. Methods: We retrospectively analyzed the initial symptoms, clinical manifestations, risk factors, neuroradiological findings, and treatment data of 75 Chinese children aged between 1 month and 14 years (median 5.7 years) who were diagnosed with AIS in our hospital between 2013 and 2018. Results: Among these 75 cases of childhood AIS, 53 patients (70.67%) were male, and the male-to-female ratio was 2.41:1. A total of 55 cases (73.33%) had respiratory tract infection with fever. Seventy cases had lesions in the basal ganglia (46 left, 24 right). All patients were treated conservatively without thrombolytic therapy. Intravenous immunoglobulin treatment was given to children with fever and drowsiness. Conclusion: Infection was an important risk factor for children with AIS in China. Infection and thrombophilia risk factors were more likely to occur in isolation. The stroke lesions commonly occurred in the basal ganglia region.

Aspirin in childhood acute ischemic stroke: The evidence for treatment and efficacy testing

Aspirin is the most commonly prescribed antiplatelet agent worldwide, but evidence supporting its use varies by age and disease process. Despite its frequent use in childhood acute ischemic stroke prevention and management, major knowledge gaps exist about optimal pediatric aspirin use, particularly in this setting, where high-quality clinical trials are urgently needed. This review focuses upon the evidence for aspirin use in childhood acute ischemic stroke, includes a summary of aspirin pharmacology to highlight misconceptions and common clinical situations which may limit its efficacy, and discusses the techniques and potential role of laboratory monitoring of aspirin efficacy in children.

Recurrent stroke: the role of thrombophilia in a large international pediatric stroke population

Risk factors for arterial ischemic stroke in children include vasculopathy and prothrombotic risk factors but their relative importance to recurrent stroke is uncertain. Data on recurrent stroke from databases held in Canada (Toronto), Germany (Kiel-Lübeck/Münster), and the UK (London/Southampton) were pooled. Data were available from 894 patients aged 1 month to 18 years at first stroke (median age, 6 years) with a median follow-up of 35 months. Among these 894 patients, 160 (17.9%) had a recurrence between 1 day and 136 months after the first stroke (median, 3.1 months). Among 288 children with vasculopathy, recurrence was significantly more common [hazard ratio (HR) 2.5, 95% confidence interval (95% CI) 1.92-3.5] compared to the rate in children without vasculopathy. Adjusting for vasculopathy, isolated antithrombin deficiency (HR 3.9; 95% CI: 1.4-10.9), isolated elevated lipoprotein (a) (HR 2.3; 95% CI: 1.3-4.1), and the presence of more than one prothrombotic risk factor (HR 1.9; 95% CI: 1.12-3.2) were independently associated with an increased risk of recurrence. Recurrence rates calculated per 100 person-years were 10 (95% CI: 3-24) for antithrombin deficiency, 6 (95% CI: 4-9) for elevated lipoprotein (a), and 13 (95% CI: 7-20) for the presence of more than one prothrombotic risk factor. Identifying children at increased risk of a second stroke is important in order to intensify measures aimed at preventing such recurrences.

Impact of Childhood Arterial Ischemic Stroke Standardized Classification and Diagnostic Evaluation Classification on Further Course of Arteriopathy and Recurrence of Childhood Stroke

Background and Purpose- Arterial ischemic stroke (AIS) in childhood is a severe disease with potentially lifelong restrictions. Apart from cardiac or prothrombotic embolism, arteriopathy has been identified as a major cause and significant target of secondary stroke prevention. The Childhood Arterial Ischemic Stroke Standardized Classification and Diagnostic Evaluation (CASCADE) criteria facilitate a structured tool for categorizing and reporting childhood strokes according to the underlying cause. Our study aims to identify the prognostic value of CASCADE classification on admission for further course of arteriopathy and risk of stroke recurrence. Moreover, we give recommendations for follow-up imaging based on different CASCADE subgroups. Methods- Between 2004 and 2017, we identified 86 children with an acute arterial ischemic stroke classified in the 7-basic and 19-expanded subgroups of the acute CASCADE criteria. All included children were diagnosed and followed-up by magnetic resonance imaging. All arteriopathic strokes (basic subgroups 1-4 of acute CASCADE criteria) were further categorized into the chronic CASCADE criteria, including progressive, stable, reversible, and indeterminate course. Outcomes were defined as stroke recurrence and course of arteriopathy according to chronic CASCADE criteria. Associations between acute CASCADE criteria classification and stroke recurrence were assessed by Fisher exact test and between acute CASCADE criteria and chronic CASCADE criteria by Fisher exact test and Mann-Whitney U test. Results- A total of 86 children were included; of these, 57 presented with arteriopathic stroke (CASCADE 1-4) and 29 as nonarteriopathic. Unilateral cerebral arteriopathy (CASCADE 2; P=0.036) and bilateral cerebral arteriopathy (CASCADE 3; P=0.016) significantly correlated with stroke recurrence, and progressive arteriopathy significantly correlated with unilateral focal cerebral arteriopathy (P<0.001). Time points of progress of arteriopathy differed; whereas patients with unilateral focal cerebral arteriopathy presented with early median progress after 11 days, patients with bilateral cerebral arteriopathy had a significantly later median progress after 124 days (P=0.005). Conclusions- Initial CASCADE classification is associated with risk of recurrent strokes and progress of arteriopathy. Moreover, time points of arteriopathic progress vary according to the underlying cause.

Mechanical thrombectomy in children and adolescents: report of five cases and literature review

Background

Paediatric arterial ischaemic stroke is an important cause of morbidity and mortality among children. Currently, there are no recommendations regarding mechanical thrombectomy in children despite overwhelming evidence of improved outcomes in adults. Therefore, the need for individual case reports and case series is important to highlight potential advantages and disadvantages in this approach.

Case descriptions

We retrospectively searched our prospectively maintained database of patients undergoing mechanical thrombectomy for ischaemic stroke. We describe five children, aged between 7 and 17, who underwent mechanical thrombectomy for acute ischaemic stroke. We provide an account of their clinical presentations, operative treatment and postoperative outcome.

Discussion

Mechanical thrombectomy in children, especially older children, can be performed safely and with existing devices. Although a randomised controlled trial would provide compelling evidence of the potential advantages to this technique, the lack of this should not prevent the use of this procedure by trained neurointerventionists.

Expanding the Distinctive Neuroimaging Phenotype of ACTA2 Mutations

BACKGROUND AND PURPOSE

Arg179His mutations in ACTA2 are associated with a distinctive neurovascular phenotype characterized by a straight course of intracranial arteries, absent basal Moyamoya collaterals, dilation of the proximal internal carotid arteries, and occlusive disease of the terminal internal carotid arteries. We now add to the distinctive neuroimaging features in these patients by describing their unique constellation of brain malformative findings that could flag the diagnosis in cases in which targeted cerebrovascular imaging has not been performed.

MATERIALS AND METHODS

Neuroimaging studies from 13 patients with heterozygous Arg179His mutations in ACTA2 and 1 patient with pathognomonic clinicoradiologic findings for ACTA2 mutation were retrospectively reviewed. The presence and localization of brain malformations and other abnormal brain MR imaging findings are reported.

RESULTS

Characteristics bending and hypoplasia of the anterior corpus callosum, apparent absence of the anterior gyrus cinguli, and radial frontal gyration were present in 100% of the patients; flattening of the pons on the midline and multiple indentations in the lateral surface of the pons were demonstrated in 93% of the patients; and apparent "squeezing" of the cerebral peduncles in 85% of the patients.

CONCLUSIONS

Because α-actin is not expressed in the brain parenchyma, only in vascular tissue, we speculate that rather than a true malformative process, these findings represent a deformation of the brain during development related to the mechanical interaction with rigid arteries during the embryogenesis.

Breath-Hold Blood Oxygen Level-Dependent MRI: A Tool for the Assessment of Cerebrovascular Reserve in Children with Moyamoya Disease

BACKGROUND AND PURPOSE

There is a critical need for a reliable and clinically feasible imaging technique that can enable prognostication and selection for revascularization surgery in children with Moyamoya disease. Blood oxygen level-dependent MR imaging assessment of cerebrovascular reactivity, using voluntary breath-hold hypercapnic challenge, is one such simple technique. However, its repeatability and reliability in children with Moyamoya disease are unknown. The current study sought to address this limitation.

MATERIALS AND METHODS

Children with Moyamoya disease underwent dual breath-hold hypercapnic challenge blood oxygen level-dependent MR imaging of cerebrovascular reactivity in the same MR imaging session. Within-day, within-subject repeatability of cerebrovascular reactivity estimates, derived from the blood oxygen level-dependent signal, was computed. Estimates were associated with demographics and intellectual function. Interrater reliability of a qualitative and clinically applicable scoring scheme was assessed.

RESULTS

Twenty children (11 males; 12.1 ± 3.3 years) with 30 MR imaging sessions (60 MR imaging scans) were included. Repeatability was "good" on the basis of the intraclass correlation coefficient (0.70 ± 0.19). Agreement of qualitative scores was "substantial" (κ = 0.711), and intrarater reliability of scores was "almost perfect" (κ = 0.83 and 1). Younger participants exhibited lower repeatability (P = .027). Repeatability was not associated with cognitive function (P > .05). However, abnormal cerebrovascular reactivity was associated with slower processing speed (P = .015).

CONCLUSIONS

Breath-hold hypercapnic challenge blood oxygen level-dependent MR imaging is a repeatable technique for the assessment of cerebrovascular reactivity in children with Moyamoya disease and is reliably interpretable for use in clinical practice. Standardization of such protocols will allow further research into its application for the assessment of ischemic risk in childhood cerebrovascular disease.

Recent developments and new frontiers in childhood arterial ischemic stroke

This review will discuss important developments in childhood arterial ischemic stroke over the past decade, focusing on improved understanding of the causes, consequences, and targets for intervention. Risk factors for childhood arterial ischemic stroke are different to adults. Infections, particularly herpes group viruses, are important precipitants for stroke. Non-atherosclerotic arteriopathies are the most common cause of childhood arterial ischemic stroke and an important predictor of recurrent events. Recent advances include the identification of serum biomarkers for inflammation and endothelial injury, and imaging biomarkers to monitor for vascular progression. Multicenter trials of immunotherapies in focal cerebral arteriopathies are currently in development. Recognition of clinical and radiological phenotypic patterns has facilitated the discovery of multisystem disorders associated with arterial ischemic stroke including ACTA2 arteriopathy and adenosine deaminase 2 deficiency. Identification of these Mendelian disorders provide insights into genetic mechanisms of disease and have implications for medical and surgical management. In contrast to adults, there are long diagnostic delays in childhood arterial ischemic stroke. Refinement of pediatric Code Stroke protocols and clinical decision support tools are essential to improve diagnostic certainty and improve access to reperfusion therapies. Children do not recover better than adults following arterial ischemic stroke, with more than half of survivors having long-term impairments. The physical, cognitive, and behavioral consequences of childhood arterial ischemic stroke are increasingly reported but further research is required to understand their impact on participation, quality of life, psychosocial, and family functioning. Longitudinal studies and the use of advanced imaging techniques, to understand neurobiological correlates of functional reorganization, are essential to developing targeted intervention strategies to facilitate recovery.

Proteomic analysis of plasma from children with sickle cell anemia and silent cerebral infarction

Silent cerebral infarction is the most common neurological abnormality in children with sickle cell anemia, affecting 30-40% of 14 year olds. There are no known biomarkers to identify children with silent cerebral infarcts, and the pathological basis is also unknown. We used an unbiased proteomic discovery approach to identify plasma proteins differing in concentration between children with and without silent cerebral infarcts. Clinical parameters and plasma samples were analysed from 51 children (mean age 11.8 years, range 6-18) with sickle cell anemia (HbSS). A total of 19 children had silent cerebral infarcts and 32 normal MRI; the children with silent infarcts had lower HbF levels (8.6 vs. 16.1%, P=0.049) and higher systolic blood pressures (115 vs. 108.6, P=0.027). Plasma proteomic analysis showed 13 proteins increased more than 1.3 fold in the SCI patients, including proteins involved in hypercoagulability (α2-antiplasmin, fibrinogen−γ chain, thrombospondin-4), inflammation (α2-macroglobulin, complement C1s and C3), and atherosclerosis (apolipoprotein B-100). Higher levels of gelsolin and retinol-binding protein 4 were also found in the population with silent infarcts, both of which have been linked to stroke. We investigated the genetic basis of these differences by studying 359 adults with sickle cell disease (199 with silent cerebral infarcts, 160 normal MRIs), who had previously undergone a genome-wide genotyping array. None of the genes coding for the differentially expressed proteins were significantly associated with silent infarction. Our study suggests that silent cerebral infarcts in sickle cell anemia may be associated with higher systolic blood pressure, lower HbF levels, hypercoagulability, inflammation and atherosclerotic lipoproteins.

Elevated serum lipoprotein(a) as a risk factor for combined intracranial and extracranial artery stenosis in a child with arterial ischemic stroke: A case report

RATIONALE

Stroke is an uncommon disease in childhood with an estimated incidence of 1 to 6 per 100,000 and stenoocclusive arteriopathy is the main risk factor of recurrent pediatric arterial ischemic stroke (AIS). Dyslipidemia may influence strongly before puberty and in late adolescence when plasma levels are naturally highest.

PATIENT CONCERNS

An 11-year-old male presented with acute onset seizure, a drowsy mentality, and right hemiplegia.

DIAGNOSES

Magnetic resonance (MR) angiogram demonstrated occlusion of distal basilar artery and left vertebral arteries. Serum Lp(a) was significantly increased as 269 nmol/L (normal<75 nmol/L) only. Thus, he was diagnosed as pediatric AIS.

INTERVENTIONS

He was started on aspirin (100 mg/day) for secondary stroke prevention and received nicotinic acid (2 g/day) as a Lp(a)-lowering agent.

OUTCOMES

Consciousness gradually improved and the patient regained a normal orientation after 2 weeks. The Lp(a) level was reduced to 48 nmol/L after nicotinic acid administration.

LESSONS

High Lp(a) level may be considered in the risk profile assessment of pediatric AIS. Niacin and certain inhibitors of cholesteryl ester transfer protein can be considered to reduce Lp(a).

Moyamoya Disease in Children: Results From the International Pediatric Stroke Study

This study aimed to describe children with moyamoya disease from an international multicenter stroke database, and explore risk factors for stroke recurrence. We reviewed data of children >28-days old with moyamoya disease enrolled in the International Pediatric Stroke Study from January 2003 to March 2013. A total of 174 children from 32 sites and 14 countries had moyamoya disease; median age 7.4 years, 49% male. Of these, 90% presented with ischemic stroke, 7.5% with transient ischemic attack, and 2.5% with hemorrhagic stroke. One-third of patients had moyamoya syndrome. Stroke recurrence was 20% over median follow-up of 13 months; 9% had multiple recurrences. Children treated with surgical revascularization were less likely to have stroke recurrence ( P = .046). Moyamoya disease accounted for 8% of arterial strokes in this international pediatric stroke registry. One-third of pediatric patients with moyamoya disease have an underlying syndromic condition. Surgical revascularization is effective at reducing the incidence of stroke recurrence.

Incidence of Recurrence in Posterior Circulation Childhood Arterial Ischemic Stroke

Importance

Childhood arterial ischemic stroke (CAIS) affects approximately 1.6 per 100 000 children per year, while stroke recurs in up to 20% of patients at 5 years. Factors determining the risk of recurrence are incompletely understood.

Objective

To investigate the incidence of the recurrence of CAIS in the posterior and anterior circulations to determine if the risk differs between the 2 locations.

Design, Setting, and Participants

A retrospective analysis of CAIS was conducted among children enrolled in a single-center prospective consecutive cohort at The Children's Hospital of Philadelphia between January 1, 2006, and January 1, 2015. Children with confirmed CAIS occurring between 29 days and 17.99 years were evaluated for inclusion. Patients were excluded if infarcts were located in both the anterior and posterior distributions or if CAIS occurred as a complication of intracranial surgery or brain tumor.

Main Outcomes and Measures

Stroke recurrence.

Results

The study population included 107 patients (75 boys [70.1%] and 32 girls [29.9%]; median age at AIS, 7.7 years [interquartile range, 3.1-13.6 years]). Sixty-one children had anterior circulation CAIS (ACAIS) and 46 had posterior circulation CAIS (PCAIS). Median follow-up was 20.9 months (interquartile range, 8.7-40.4 months). For ACAIS, recurrence-free survival was 100% at 1 month and 96% (95% CI, 85%-99%) at 1 and 3 years. For PCAIS, recurrence-free survival was 88% (95% CI, 75%-95%) at 1 month and 81% (95% CI, 66%-90%) at 1 and 3 years. The hazard ratio for recurrence after PCAIS compared with ACAIS was 6.4 (95% CI, 1.4-29.8; P = .02) in univariable analysis and 5.3 (95% CI, 1.1-26.4; P = .04) after adjusting for sex and cervical dissection.

Conclusions and Relevance

We identified a subgroup of patients that comprise more than 80% of recurrences of CAIS. Three years after incident stroke, 19% of children with PCAIS had a recurrence compared with 4% of patients with ACAIS. Different mechanisms of stroke may account for this difference. Children with PCAIS may warrant increased monitoring. This study highlights the necessity for further research focused on recurrence prevention.

Arterial Ischemic Stroke in Children and Young Adults

PURPOSE OF REVIEW

This article reviews risk factors, recurrence risk, evaluation, management, and outcomes of arterial ischemic stroke in children and young adults.

RECENT FINDINGS

The risk for recurrence and mortality appear to be low for neonatal and childhood stroke. Most children have relatively mild deficits, but those who have greater neurologic deficits, poststroke epilepsy, or strokes early in life are at risk for lower overall cognitive function. Stroke recurrence and long-term mortality after stroke in young adults are greater than originally thought. Cognitive impairments, depression, and anxiety are associated with higher levels of poststroke unemployment and represent targets for improved poststroke care. Poststroke care in young adults involves more than medical management. Self-reported memory and executive function impairments may be more severe than what is detected by objective measures. Assessment of possible cognitive impairments and appropriate management of psychological comorbidities are key to maximizing the long-term functional outcome of stroke survivors.

SUMMARY

Childhood and young adult stroke survivors survive for many more years than older patients with stroke. To ensure that these survivors maximize the productivity of their lives, neurologists must not only optimize medical management but also recognize that impairments in cognition and mood may be remediable barriers to long-term functional independence.

Immunotherapy for arterial ischaemic stroke in childhood: a systematic review

BACKGROUND

There is little evidence about either prevention or treatment of childhood arterial ischaemic stroke (AIS). However, drugs that regulate the immune and inflammatory response could theoretically prevent occurrence or recurrence of AIS. Additionally, as an acute treatment, they may limit the neurological damage caused by AIS. Here, we systematically review the evidence on the use of immunotherapy in childhood AIS.

DESIGN

A systematic review of publications in databases Embase and Medline from inception. All types of evidence were included from trials, cohorts, case-control and cross-sectional studies and case reports.

RESULTS

34 reports were included: 32 observational studies and 2 trials. Immunotherapy was used in two key patient groups: arteriopathy and acute infection. The majority were cases of varicella and primary angiitis of the central nervous system. All three cohorts and 80% of the case studies were treated with steroids. Recurrence rates were low. Analytical studies weakly associated steroids with lower odds of new stroke and neurological deficits, and better cognitive outcomes in the context of Moyamoya disease and tuberculosis.

CONCLUSIONS

Immunotherapies are used in children with AIS, mainly as steroids for children with arteriopathy. However, there is currently little robust evidence to either encourage or discourage this practice. There is weak evidence consistent with the hypothesis that in certain children at risk, steroids may both reduce the risk of occurrent/recurrent stroke and enhance neurological outcomes. As the potential benefit is still uncertain, this indicates that a trial of steroids in childhood AIS may be justified.

Harnessing Neuroimaging Capability in Pediatric Stroke: Proceedings of the Stroke Imaging Laboratory for Children Workshop

On June 5, 2015 the International Pediatric Stroke Study and the Stroke Imaging Laboratory for Children cohosted a unique workshop focused on developing neuroimaging research in pediatric stroke. Pediatric neurologists, neuroradiologists, interventional neuroradiologists, physicists, nurse practitioners, neuropsychologists, and imaging research scientists from around the world attended this one-day meeting. Our objectives were to (1) establish a group of experts to collaborate in advancing pediatric neuroimaging for stroke, (2) develop consensus clinical and research magnetic resonance imaging protocols for pediatric stroke patients, and (3) develop imaging-based research strategies in pediatric ischemic stroke. This article provides a summary of the meeting proceedings focusing on identified challenges and solutions and outcomes from the meeting. Further details on the workshop contents and outcomes are provided in three additional articles in the current issue of Pediatric Neurology.

Stroke and Hypertension in Children and Adolescents

Hypertension is the single most important modifiable risk factor for adult stroke. Stroke mortality has significantly decreased over the last 5 decades; this decline has been mainly associated to improved blood pressure control. Though much less prevalent than in adults, stroke is an increasingly recognized cause of morbidity and mortality in children. Although hypertension has not been strongly identified as a risk factor in childhood stroke yet, there is preliminary evidence that suggests that elevated blood pressure may be associated with stroke in children. This review summarizes the literature that may link elevated blood pressure to the development of childhood ischemic and hemorrhagic stroke. The authors suggest that elevated blood pressure may be a significant risk factor that, alone or in combination with other multiple risk factors, leads to the development of stroke in childhood. It is therefore recommend that blood pressure be measured and assessed carefully in every child presenting with acute stroke.

[Stroke in children and adolescents: a formation of a pediatric register]

AIM

To optimize a system of medical care, introduction of treatment and diagnostic guidelines, including secondary stroke prevention and rehabilitation measures, by implementation of pediatric stroke registry.

MATERIAL AND METHODS

Fifty-seven patients, aged from 1 year to 17 years 11 months, included into the Moscow city registry of pediatric stroke were examined. Forty-two patients suffered ischemic stroke and 15 hemorrhagic stroke.

RESULTS AND CONCLUSION

The diagnostic search for the causes of pediatric stroke is difficult due to the wide variety of etiologic factors and high frequency of their combinations. This confirms the necessity of multidisciplinary approach to the management of children and adolescents in the acute phase of stroke in a multiprofile hospital with the following specialized ambulatory care.

Sickle Cell Disease and Stroke: Diagnosis and Management

Both adult and pediatric patients with sickle cell disease face a higher risk of stroke than the general population. Given the different underlying pathophysiology predisposing these patients to stroke, providers should be aware of differences in guidelines for stroke management. This paper reviews diagnostic considerations and recommendations during the evaluation and acute management of patients with sickle cell disease presenting with stroke, focusing on recent updates in the literature. Given the high recurrence rate of stroke in these patients, secondary prevention and curative measures will also be reviewed.

Outcome and recurrence 1 year after pediatric arterial ischemic stroke in a population-based cohort

OBJECTIVE

Arterial ischemic stroke (AIS) is an important cause of acquired brain injury in children. Few prospective population-based studies of childhood AIS have been completed. We aimed to investigate the outcome of childhood AIS 12 months after the event in a population-based cohort.

METHODS

Children aged 29 days to < 16 years with radiologically confirmed AIS occurring over a 1-year period residing in southern England (population = 5.99 million children) were eligible for inclusion. Outcome was assessed during a home visit using the Pediatric Stroke Outcome Measure (PSOM). Parental impressions of recovery were assessed using the Pediatric Stroke Recurrence and Recovery Questionnaire. PSOM score was estimated via telephone interview or clinician interview whenever home visit was not possible.

RESULTS

Ninety-six children with AIS were identified. Two children were lost to follow-up. Nine of 94 (10%) children died before the 12-month follow-up. One child had an AIS recurrence. PSOM scores were available for 78 of 85 living children at follow-up. Thirty-nine of 78 (50%) had a good outcome (total PSOM score < 1), and 39 of 78 (50%) had a poor outcome. Seizures at onset of AIS were associated with a poor outcome (odds ratio = 3.5, 95% confidence interval = 1.16-10.6). Twenty-eight of 73 (38%) children were judged by their carers to have fully recovered. Ten of 84 (12%) children had recurrent seizures, and 17 of 84 (20%) reported recurrent headaches.

INTERPRETATION

AIS carries a significant risk of mortality and long-term neurological deficit. However, the rates of mortality, recurrence, and neurological impairment were markedly lower in this study than previously published figures in the United Kingdom. Ann Neurol 2016;79:784-793.

Herpesvirus Infections and Childhood Arterial Ischemic Stroke: Results of the VIPS Study

BACKGROUND

Epidemiological studies demonstrate that childhood infections, including varicella zoster virus, are associated with an increased risk of arterial ischemic stroke (AIS). Other herpesviruses have been linked to childhood AIS in case reports. We sought to determine whether herpesvirus infections, which are potentially treatable, increase the risk of childhood AIS.

METHODS AND RESULTS

We enrolled 326 centrally confirmed cases of AIS and 115 stroke-free controls with trauma (29 days to 18 years of age) with acute blood samples (≤3 weeks after stroke/trauma); cases had convalescent samples (7-28 days later) when feasible. Samples were tested by commercial enzyme-linked immunosorbent assay kits for immunoglobulin M/immunoglobulin G antibodies to herpes simplex virus 1 and 2, cytomegalovirus, Epstein-Barr virus, and varicella zoster virus. An algorithm developed a priori classified serological evidence of past and acute herpesvirus infection as dichotomous variables. The median (quartiles) age was 7.7 (3.1-14.3) years for cases and 10.7 (6.9-13.2) years for controls (P=0.03). Serological evidence of past infection did not differ between cases and controls. However, serological evidence of acute herpesvirus infection doubled the odds of childhood AIS, even after adjusting for age, race, and socioeconomic status (odds ratio, 2.2; 95% confidence interval, 1.2-4.0; P=0.007). Among 187 cases with acute and convalescent blood samples, 85 (45%) showed evidence of acute herpesvirus infection; herpes simplex virus 1 was found most often. Most infections were asymptomatic.

CONCLUSIONS

Herpesviruses may act as a trigger for childhood AIS, even if the infection is subclinical. Antivirals like acyclovir might have a role in the prevention of recurrent stroke if further studies confirm a causal relationship.

Risk of Recurrent Arterial Ischemic Stroke in Childhood: A Prospective International Study

BACKGROUND AND PURPOSE

Published cohorts of children with arterial ischemic stroke (AIS) in the 1990s to early 2000s reported 5-year cumulative recurrence rates approaching 20%. Since then, utilization of antithrombotic agents for secondary stroke prevention in children has increased. We sought to determine rates and predictors of recurrent stroke in the current era.

METHODS

The Vascular Effects of Infection in Pediatric Stroke (VIPS) study enrolled 355 children with AIS at 37 international centers from 2009 to 2014 and followed them prospectively for recurrent stroke. Index and recurrent strokes underwent central review and confirmation, as well as central classification of causes of stroke, including arteriopathies. Other predictors were measured via parental interview or chart review.

RESULTS

Of the 355 children, 354 survived their acute index stroke, and 308 (87%) were treated with an antithrombotic medication. During a median follow-up of 2.0 years (interquartile range, 1.0-3.0), 40 children had a recurrent AIS, and none had a hemorrhagic stroke. The cumulative stroke recurrence rate was 6.8% (95% confidence interval, 4.6%-10%) at 1 month and 12% (8.5%-15%) at 1 year. The sole predictor of recurrence was the presence of an arteriopathy, which increased the risk of recurrence 5-fold when compared with an idiopathic AIS (hazard ratio, 5.0; 95% confidence interval, 1.8-14). The 1-year recurrence rate was 32% (95% confidence interval, 18%-51%) for moyamoya, 25% (12%-48%) for transient cerebral arteriopathy, and 19% (8.5%-40%) for arterial dissection.

CONCLUSIONS

Children with AIS, particularly those with arteriopathy, remain at high risk for recurrent AIS despite increased utilization of antithrombotic agents. Therapies directed at the arteriopathies themselves are needed.