Mechanical thrombectomy for pediatric stroke arising from an atrial myxoma: case report

Safety and Outcomes of Mechanical Thrombectomy in Acute Ischemic Stroke Attributable to Cardiological Diseases: A Scoping Review

There is limited evidence on the outcomes and safety of mechanical thrombectomy (MT) among patients with acute ischemic stroke (AIS) in the context of cardiac diseases. Our study reviews MT in AIS within the context of cardiac diseases, aiming to identify existing and emerging needs and gaps. PubMed and Scopus were searched until December 31, 2023, using a combination of cardiological diseases and "mechanical thrombectomy" or "endovascular treatment" as keywords. Study design included case reports/series, observational studies, randomized clinical trials, and meta-analyses/systematic reviews. We identified 943 articles, of which 130 were included in the review. Results were categorized according to the cardiac conditions. MT shows significant benefits in patients with atrial fibrillation (n=139) but lacks data for stroke occurring after percutaneous coronary intervention (n=2) or transcatheter aortic valve implantation (n=5). MT is beneficial in AIS attributable to infective endocarditis (n=34), although functional benefit may be limited. Controversy surrounds the functional outcomes and mortality of patients with AIS with heart failure undergoing MT (n=11). Despite technical challenges, MT appears feasible in aortic dissection cases (n=4), and in patients with left ventricular assist device or total artificial heart (n=10). Data on AIS attributable to congenital heart disease (n=4) primarily focus on pediatric cases requiring technical modifications. Treatment outcomes of MT in patients with cardiac tumors (n=8) vary because of clot consistency differences. After cardiac surgery stroke, MT may improve outcomes with early intervention (n=13). Available data outline the feasibility of MT in patients with AIS attributable to large-vessel occlusion in the context of cardiac diseases.

Systematic Review and Case of Thrombectomy for Pediatric Stroke Due to Myxoma Embolism

BACKGROUND

Stroke presentation secondary to a cardiac myxoma thromboembolism is rare in the pediatric population. Because of such rarity, the reported cases in the literature are primarily case reports. Additionally, general pediatric stroke management lacks evidence-based guidelines because of its low incidence and lack of clinical trials. In pediatric strokes identified from a cardiac myxoma, the incidence favors boys with the classical presentation of unilateral weakness and aphasia. We present a pediatric patient who presented with strokelike symptoms secondary to an intracranial embolus from a previously undiagnosed cardiac myxoma.

METHODS

We performed a systematic review by searching PubMed, Google Scholar, Web of Science, and Embase databases for cases of pediatric myxoma causing stroke (n = 2431) and identified 19 reported uses of surgical management in treating pediatric patients who present with stroke symptoms secondary to a cardiac myxoma thromboembolism.

RESULTS

The most common imaging modality was magnetic resonance imaging in 42% of cases, computed tomography in 36.8%, followed by computed tomography angiography in 31.6% of cases. Of these 19 children treated with procedures, 36.8% of pediatric patients aged between 4 and 14 years underwent neurosurgery (n = 7).

CONCLUSIONS

We describe an urgent mechanical thrombectomy and share preoperative and postoperative images and pathology slides confirming a stroke from myxoma origin. We provide added insight in the safe use of mechanical thrombectomy as treatment for pediatric strokes secondary to a thromboembolism.

Mechanical thrombectomy for the treatment of large vessel occlusion due to cancer-related cerebral embolism: A systematic review

BACKGROUND

Cancer-related cerebral embolism due to direct tumor embolization results in a rare acute ischemic stroke with large vessel occlusion (LVO). Despite the established status of mechanical thrombectomy (MT) in LVO management, its effectiveness and safety remains inadequately explored in this specific patient group.

METHODS

We conducted a systematic review following Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, using the Nested Knowledge AutoLit software, encompassing databases like Embase, PubMed, Scopus, and Web of Science, from their inception up to 9 May 2023.

RESULTS

In the review of 35 studies encompassing 37 cases, mean patient age was 52 years, and 30% were female. Cardiac myxoma (29.7%), cardiac papillary fibroelastoma (16.2%), and squamous cell carcinoma of the lung (8.1%) were the most frequent underlying cancers. The left middle cerebral artery was the most commonly affected occlusion site (24.3%). Of the patients, 67.5% underwent MT alone, while 32.5% received MT combined with intravenous thrombolysis. Successful reperfusion (thrombolysis in cerebral infarction (TICI) 2b-3) was achieved in 89.1% of cases, with 59.4% reaching TICI 3. Functional independence was observed in 29.7% of patients.

CONCLUSION

While limitations exist, this comprehensive study highlights the potential benefits of MT in a patient group historically excluded from major trials, warranting further investigation.

Clinical features, risk factors and survival in cardiac myxoma-related ischemic stroke: A multicenter case-control study

BACKGROUND

Cardiac myxoma (CM) is an important etiology of stroke in young adults, but studies on CM-related ischemic stroke (CM-IS) are limited and conflicting. Hence, we investigated clinical characterizations, risk factors of CM-IS, and short-term survival after surgical resection.

METHODS

We performed a retrospective analysis of data from all CM patients at three referral management centers and conducted follow-up examination.

RESULTS

Among 414 CM patients, 402 were recruited for further analysis, including 54 patients with CM-IS and 348 patients with CM without stroke (Non-stroke). In the acute phase, patients presented with NIHSS 3 (interquartile range: 0-10) and clinical presentation comprising neurological, cardiac and constitutional symptoms. Multivariate analysis showed that the factors associated with an increased risk of CM-IS were tumor width < 30 mm [OR = 2.652, 95% CI: 1.061-6.627, P = 0.037], tumors with high-mobility (OR = 2.700, 95% CI: 1.357-5.371, P = 0.005), thrombus on the tumor surface (OR = 1.856, 95% CI: 1.003-3.434, P = 0.049), and lower B-type natriuretic peptide (BNP) levels (OR = 0.995, 95% CI: 0.989-0.999, P = 0.047). The overall three-year survival rate was 95.7% (95% CI: 94.9-96.5) in CM-IS patients who underwent surgery.

CONCLUSIONS

CM-IS patients had mild or moderate neurologic deficits with various presentations at disease onset. Narrower tumor width, tumors with high-mobility, thrombus on the tumor surface, and lower BNP levels are potential predictors of CM-IS development. Surgical removal of CM is safe and efficacious in patients with CM-IS.

Current status of diagnosis and treatment of primary benign cardiac tumors in children

Primary cardiac tumors in children are exceedingly rare overall, which benign account for most part. The onset of the disease is occult, while the clinical manifestations are non-specific-patients may be asymptomatic or show a range of obstructive, arrhythmic, embolic or systemic symptoms. The clinical presentations generally depend on the tumors’ size, localization, and pace of growth of the tumor. Moreover, the diagnosis needs comprehensive judgment based on imaging results and pathological examination. With advances in cardiac imagining and the introduction of cardiopulmonary support, the diagnosis and treatment of these rare tumors have improved the prognosis and outlook for benign tumors. To sum up the above, we sought to integrate articles from recent years for the latest comprehensive review of the clinical manifestations, imaging characteristics, clinic pathologic features and treatment of benign cardiac tumors in children to provide a broader idea for pediatricians to recognize and treat such diseases.

Delayed multiple intracranial aneurysms caused by left atrial myxoma: a case report and literature review

Intracranial aneurysm may appear even after the removal of the cardiac myxoma. However, the pathogenesis and treatment of such aneurysm lesions are not clear. The study aimed to explore the clinical and imaging manifestation, hypothetical pathogenesis, and therapy in one case of left atrial myxoma causing multiple intracranial aneurysms. A 14-year-old male displayed a 3-hour history of episodic loss of consciousness and right hemiplegia after a leapfrog-like movement. The myxoma was diagnosed by a combination of clinical examination, leading to the diagnosis of mitral dynamic obstruction with a Grade III mitral diastolic murmur and tumor plop; magnetic resonance imaging, revealing multiple ischemic sites in both semi-oval centers; and transthoracic echocardiography, demonstrating a mitral valve obstruction. The myxoma was removed surgically; however, computed tomography angiography showed multiple intracranial aneurysms in both middle cerebral arteries 18 months after resection of the atrial myxoma. After conservative treatment, the patient had no neurological dysfunction symptoms for 5 years after myxoma resection. His condition is relatively stable. In conclusion, resection of the atrial myxoma may eliminate the early neurological symptoms, but it cannot ensure the nonoccurrence of delayed intracranial aneurysms. The neoplastic process theory was favored for explaining the aneurysm development in this case. According to the specific conditions of the patient, a combination of open surgery, chemotherapy, radiotherapy, and coil embolization is recommended.

Mechanical Thrombectomy in Embolic Cardiac Myxoma: Case Report and Literature Review

Myxomas are the most common cardiac tumors and present clinically with cardiac manifestations, systemic constitutional symptoms, and embolic events. Posterior circulation involvement occurs in approximately 20 percent of cerebral ischemic events.The endovascular technique is an established life-saving therapy for eligible patients upto 24 hours from symptom onset. However, the role of endovascular management in embolic atrial myxoma remains unknown with no international consensus guidelines for the management of stroke in such patient population. Here, we present a case report of an embolic posterior circulation stroke in a young female treated with mechanical thrombectomy at 23 hours from symptom onset. To the best of our knowledge, this is the first thrombectomy case in posterior circulation with embolism from myxoma. Further workup confirmed an atrial myxoma which was resected. We also review the previous cases with mechanical thrombectomy done in such cases.

Higher-Quality Data Collection Is Critical to Establish the Safety and Efficacy of Pediatric Mechanical Thrombectomy

BACKGROUND AND PURPOSE

Because children often have lifelong morbidity after stroke, there is considerable enthusiasm to pursue mechanical thrombectomy in childhood stroke based on literature reports. However, current published data may reflect inconsistent reporting and publication bias, which limit the ability to assess safety and efficacy of mechanical thrombectomy in childhood stroke.

METHODS

This retrospective cohort study compared reporting quality and clinical outcomes for mechanical thrombectomy between a trial-derived cohort of 42 children treated with mechanical thrombectomy for acute stroke at study sites and 133 patients reported in the literature. National Institutes of Health Stroke Scale at baseline, 24 hours after mechanical thrombectomy, and at discharge were compared between study site patients and literature patients. Odds ratios (ORs) were used to compare reporting frequencies. Proportional odds logistic regression was used to compare outcomes.

RESULTS

Premechanical thrombectomy National Institutes of Health Stroke Scale was available in 93% of study patients compared with 74% of patients in the literature (OR, 4.42 [95% CI, 1.47-19.89]). Postmechanical thrombectomy National Institutes of Health Stroke Scale was available in 69% of study patients compared with 29% of literature cases at 24 hours (OR, 5.48 [95% CI, 2.62-12.06]), and 64% of study patients compared with 32% of cases at discharge (OR, 3.85 [95% CI, 1.87-8.19]). For study sites, median scores were 12 at baseline, 9 at 24 hours, and 5 at discharge. Median scores in case reports were 15 at baseline, 4 at 24 hours, and 3 at discharge. ORs for differences in outcomes between groups were 5.97 (95% CI, 2.28-15.59) at 24 hours and 3.68 (95% CI, 1.45-9.34) at discharge.

CONCLUSIONS

Study site patients had higher rates of National Institutes of Health Stroke Scale reporting and worse short-term outcomes compared with literature reports. Rigorous data collection is needed before treatment guidelines for pediatric mechanical thrombectomy can be developed.

Endovascular treatment of pediatric ischemic stroke: A single center experience and review of the literature

INTRODUCTION

Mechanical thrombectomy is standard treatment for large vessel occlusion (LVO) in adults. There are no randomized controlled trials for the pediatric population. We report our single-center experience with thrombectomy of LVO in a series of pediatric patients, and perform a review of the literature.

METHODS

Retrospective review of consecutive pediatric thrombectomy cases between 2011 and 2018. Demographic variables, imaging data, technical aspects and clinical outcome were recorded.

RESULTS

In a period of 7 years, 7 children were treated for LVO at our center. Median age was 13 (2-17), and median Ped-NIHSS was 15 (3-24), and the median ASPECTS was 8 (2-10). Five patients had cardiac disease, and 2 of them were under external cardiac assistance. Median time from onset of symptoms to beginning of treatment was 7h06m (2h58m-21h38m). Five patients had middle cerebral artery occlusions. Thrombectomy was performed using a stentriever in 3 patients, aspiration in 3 patients, and combined technique in 1 patient. Six patients had good recanalization (TICI 2 b/3). There were no immediate periprocedural complications. At 3 months, 4 patients (57%) were independent (mRS score <3). Two patients died, one after haemorrhagic transformation of an extensive MCA infarct, and one due to extensive brainstem ischemia in the setting of varicella vasculitis.

DISCUSSION

Selected pediatric patients with LVO may be treated with mechanical thrombectomy safely. In patients under external cardiac assistance and under anticoagulation, thrombectomy is the only alternative for treatment of LVO. A multidisciplinary approach in specialized pediatric stroke centers with trained neurointerventionalists are essential for good results.

Acute ischemic stroke in children – Should we thrombolyze?

Ischemic stroke is a major cause of acute neurological symptoms in children with significant long-term neurological sequelae. Unlike in the adult population, the clinical presentation of strokes in children may not be stereotyped. Hence, many other differential diagnostic possibilities might have to be considered in the emergency setting. Due to this heterogeneous presentation and the resultant clinical dilemma in the early detection, acute thrombolysis even now remains as a very rarely tried therapeutic option in children. Many case reports over these years have shown consistently good results of acute intravenous thrombolysis in children with tissue plasminogen activator (tPA) administered within the time frame. There are also some recent reports of endovascular interventions. However, unlike in the adult population, class 1 clinical studies and good Randomized controlled trials (RCT) are yet to emerge in children. The absence of age-appropriate safety and outcome data for the commonly used thrombolytic agents in children is another major roadblock for developing clinical guidelines and recommendations for this age group. The ambitious Thrombolysis in Pediatric Stroke (TIPS) trial had to be terminated prematurely due to poor patient enrolment. This review critically looks at the current status of the acute management of ischemic strokes in children with a specific emphasis on thrombolytic therapy. Until we have better evidence-based guidelines for this age group, it will be prudent to develop robust institutional pathways to provide this important intervention for all eligible children with acute strokes.

Cardiac Myxoma as a Rare Cause of Pediatric Arterial Ischemic Stroke: Case Report and Literature Review

BACKGROUND

Cardiac disorders are the second leading cause of pediatric arterial ischemic stroke (AIS). Limited literature is available on pediatric AIS caused by cardiac myxoma, a rare tumor in childhood.

METHODS

We describe a new case of pediatric AIS due to a previously unknown atrial myxoma and we conduct a literature review on children with AIS due to cardiac myxoma.

RESULTS

We identified 41 published pediatric cases of AIS and cardiac myxoma, including ours (56% males, median age at AIS was 11 years [range: 3-18]). AIS presentation was most frequently with hemiparesis/hemiplegia (89%). Multiple brain ischemic lesions were detected in 69% of patients, and arteriopathy in 91%. Seven patients underwent mechanical thrombectomy. At AIS presentation, 73% of children had one or more of the following clinical symptoms/signs suggesting a possible underlying cardiac myxoma: Carney's complex, cardiac auscultation abnormalities, extraneurological symptoms/signs, such as skin signs (12, 38, and 65%, respectively). Cardiac myxoma was diagnosed within 72 hours in 68% of cases. Death occurred in 11%, and 40% had persistent neurological deficits.

CONCLUSION

Neurological presentation of AIS due to cardiac myxoma is similar to that of AIS with other etiologies, although clues suggesting a possible underlying cardiac myxoma can be detected in most cases. A timely diagnosis of cardiac myxoma in patients with AIS may favor prompt identification of candidates for endovascular therapy. Therefore, we suggest that in otherwise-healthy children presenting with AIS, transthoracic echocardiography should be performed early after stroke presentation.

Thrombectomy for Stroke Caused by Cardiac Myxoma

Large vessel occlusion stroke, caused by cardiac myxoma, is a rare and severe condition with poor neurological outcomes. Currently, there are no clear guidelines for treating patients with this condition. In our case, we describe a rare case of acute ischemic stroke caused by cardiac myxoma which was successfully treated with mechanical thrombectomy. At the end of a 6 months' follow-up, her National Institutes of Health Stroke Scale score (NIHSS) had significantly improved, from 20 to 3. This result is encouraging and suggests that mechanical thrombectomy may be a feasible therapy for large vessel occlusion stroke induced by cardiac myxoma emboli.

Mechanical Thrombectomy for Acute Middle Cerebral Artery Occlusion Caused by Tumor Embolism: A Case Report

Objective

We report a case of acute middle cerebral artery (MCA) occlusion caused by tumor embolism.

Case Presentation

A 64-year-old man with lung cancer presented with sudden onset left-sided hemiparesis and sensory disturbance. Diffusion-weighted imaging (DWI) revealed hyper-intense foci in the right MCA territory and magnetic resonance angiography (MRA) demonstrated right MCA M2 segment occlusion. Mechanical thrombectomy (MT) was performed with Thrombolysis in Cerebral Infarction 2B recanalization. On histopathology, thrombus composed of fibrin and squamous cell carcinoma was observed. We diagnosed him with tumor embolism from lung cancer that invaded the pulmonary vein and the left atrium.

Conclusion

Tumor cells may be confirmed by pathological examination regardless of the morphology of the embolus. Pathological examination of the cerebral embolus is useful for the accurate diagnosis of ischemic stroke subtypes.

Pediatric Middle Cerebral Artery Occlusion with Dissection Following a Trampoline Trauma

BACKGROUND

Owing to the rarity of acute ischemic stroke in the pediatric population, evidence supporting the efficacy in children of the various treatments used in adults is scanty. This included mechanical thrombectomy for acute ischemic stroke.

CASE DESCRIPTION

we present the case of an 11-year-old female with acute left hemiparesis, numbness, and left facial droop occurring after tumbling on a trampoline. Computed tomography angiography revealed an 11-mm nonfilling defect in the right middle cerebral artery. She underwent thrombectomy approximately 8.5 hours after the onset of symptoms, and a Thrombolysis in Cerebral Infarction (TICI) scale score of 2b was achieved. She had an uneventful postoperative recovery.

CONCLUSION

Pediatric patients likely have more reserve and collateral flow and benefit from a longer therapeutic window following acute ischemic stroke.

Successful endovascular removal of a chondroblastic osteosarcoma embolus within the left middle cerebral artery

A 57-year-old woman with metastatic chondroblastic osteosarcoma developed sudden-onset right-sided weakness and aphasia. She was found to have an occluded left middle cerebral artery (M1 segment) and underwent endovascular stroke intervention with return to a normal neurological exam within 24 h. Histologic analysis of the embolus was consistent with chondroblastic osteosarcoma.

Mechanical thrombectomy in pediatric stroke: systematic review, individual patient data meta-analysis, and case series

OBJECTIVE

The role of mechanical thrombectomy in pediatric acute ischemic stroke is uncertain, despite extensive evidence of benefit in adults. The existing literature consists of several recent small single-arm cohort studies, as well as multiple prior small case series and case reports. Published reports of pediatric cases have increased markedly since 2015, after the publication of the positive trials in adults. The recent AHA/ASA Scientific Statement on this issue was informed predominantly by pre-2015 case reports and identified several knowledge gaps, including how young a child may undergo thrombectomy. A repeat systematic review and meta-analysis is warranted to help guide therapeutic decisions and address gaps in knowledge.

METHODS

Using PRISMA-IPD guidelines, the authors performed a systematic review of the literature from 1999 to April 2019 and individual patient data meta-analysis, with 2 independent reviewers. An additional series of 3 cases in adolescent males from one of the authors' centers was also included. The primary outcomes were the rate of good long-term (mRS score 0-2 at final follow-up) and short-term (reduction in NIHSS score by ≥ 8 points or NIHSS score 0-1 at up to 24 hours post-thrombectomy) neurological outcomes following mechanical thrombectomy for acute ischemic stroke in patients < 18 years of age. The secondary outcome was the rate of successful angiographic recanalization (mTICI score 2b/3).

RESULTS

The authors' review yielded 113 cases of mechanical thrombectomy in 110 pediatric patients. Although complete follow-up data are not available for all patients, 87 of 96 (90.6%) had good long-term neurological outcomes (mRS score 0-2), 55 of 79 (69.6%) had good short-term neurological outcomes, and 86 of 98 (87.8%) had successful angiographic recanalization (mTICI score 2b/3). Death occurred in 2 patients and symptomatic intracranial hemorrhage in 1 patient. Sixteen published thrombectomy cases were identified in children < 5 years of age.

CONCLUSIONS

Mechanical thrombectomy may be considered for acute ischemic stroke due to large vessel occlusion (ICA terminus, M1, basilar artery) in patients aged 1-18 years (Level C evidence; Class IIb recommendation). The existing evidence base is likely affected by selection and publication bias. A prospective multinational registry is recommended as the next investigative step.

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.

Pediatric Stroke Imaging

BACKGROUND

Pediatric stroke is a distinct clinical entity as compared with that in adults due to its unique and diverse set of etiologies. Furthermore, the role and application of diagnostic imaging has specific constraints and considerations. The intention of this article is to review these concepts in a thorough manner to offer a pediatric stroke imaging framework that providers can employ when taking care of these patients.

METHODS

A comprehensive primary and secondary literature review was performed with specific attention to the common causes of pediatric stroke, appropriate use of neuroimaging, specific imaging findings, and developing techniques which may improve our ability to accurately diagnose these patients.

RESULTS

Findings from this literature review were synthesized and summarized in order to thoroughly review the aforementioned concepts and outline the current consensus-based approach to diagnostic imaging in pediatric stroke. Furthermore, imaging findings drawn from patients seen in our institution are demonstrated to familiarize readers with pediatric stroke neuroimaging.

CONCLUSIONS

The challenges posed by pediatric stroke can be mitigated, in part, by the thoughtful application of diagnostic imaging, with the ultimate hope of improving outcomes for these vulnerable patients.

Stroke and peripheral embolisms in a pediatric patient with giant atrial myxoma: Case report and review of current literature

RATIONALE

Cerebral stroke with peripheral embolism due to left atrial myxoma is very rare in children. Misdiagnosis may occur because of nonspecific symptoms in the heart.

PATIENT CONCERNS

We present a case of a 16-year-old boy who presented with ischemic stroke and embolisms in the lower extremity, caused by a giant left atrial myxoma.

DIAGNOSES

Left atrial myxoma.

INTERVENTIONS

A giant gelatinous mass was completely excised, and the histopathological findings confirmed the diagnosis of atrial myxoma.

OUTCOMES

The temperature of the right lower extremity recovered gradually, and pulse of the right dorsalis pedis artery became palpable 10 days after the surgery. The strength of the bilateral lower extremity was level 5 at discharge.

LESSONS

Our case, along with the review of the literature, highlights the fact that myxomas often initially present with multiple embolisms but with few cardiac symptoms. Transthoracic echocardiography should be performed immediately to make a definitive diagnosis.

Mechanical thrombectomy for repeated cerebral tumor embolism from a thoracic sarcomatoid carcinoma

Cerebral embolism originating from intracardiac tumors represents a rare cause of stroke and has been documented in both adult and pediatric populations. We present a patient recently diagnosed with a right pulmonary hilum tumor, invading the pulmonary veins and the left atrium. Two consecutive episodes of large cerebral vessel occlusion in separate vascular territories occurred in the same day and were treated by mechanical thrombectomy. Embolic material retrieved on both occasions contained tumor fragments with peripheral endothelialization. To our knowledge, this is the first report with histological confirmation of cerebral embolism from an invasive extracardiac tumor.

A Systematic Review of the Causes and Management of Nonthrombotic Embolic Stroke of Tissue Origin

Introduction

Various bodily tissues have been reported to enter the arterial circulation and embolize to the brain resulting in ischemic stroke. Most frequently nonthrombotic embolic stroke (NTES) of tissue origin is iatrogenic or related to an underlying disease process. With the increase in elective surgery and intravascular procedures, NTES may increase in prevalence.

Aim

To compile a summary of the background, incidence, presentation, and treatment of NTES of tissue origin, by conducting a systematic review of the current literature.

Summary of Review

We searched EMBASE and MEDLINE for articles on NTES of tissue origin published in English with no restriction on publication date (search date June 2017). 800 articles were identified and screened and 159 articles were ultimately reviewed in full text and included in qualitative analysis. Articles deemed relevant were assessed by a second reviewer to confirm compatibility with the inclusion criteria. References of included articles were reviewed for relevant publications. We categorized the pathology of the emboli into the following groups: amniotic fluid (4 publications), tumour (60 publications), fat (43 publications), cholesterol (19 publications), and intravascular debris (12 publications). We then summarized the available literature on each cause of NTES.

Conclusions

NTES of tissue origin is an uncommon but important diagnosis to consider particularly in younger stroke patients and in certain clinical settings. Treatment for NTES is currently anecdotal and based on small case series. Embolectomy may emerge as the therapy of choice due to the longer treatment timeframe and heterogeneity of the emboli.

Primary versus secondary mechanical thrombectomy for anterior circulation stroke in children: An update

This review of the literature on the use of mechanical thrombectomy (MT) in children with acute ischemic stroke from occlusion of the internal carotid artery and the proximal middle cerebral artery (MCA) compares the efficacy and safety of primary and secondary MT. We analyzed the data reported for 24 case reports from 20 relevant articles published up to 31 December 2016 and the data of a patient treated at our institution. Eighteen cases received primary MT and 7 received secondary MT. The proportions of complete MCA recanalization, small infarcts, and asymptomatic intracranial hemorrhage were similar in both MT groups (73% [11/15] vs. 67% [4/6], 58% [7/12] vs. 60% [3/5], and 15% [2/13] vs. 17% [1/6], respectively). The proportion of favorable neurological outcomes was higher for the primary MT group (69% [11/16] vs. 43% [3/7]). We found no substantial differences in efficacy and safety between primary and secondary MT for anterior circulation stroke in children.

A Systematic Review of the Causes and Management of Ischaemic Stroke Caused by Nontissue Emboli

Introduction

The inadvertent or purposeful introduction of foreign bodies or substances can lead to cerebral infarction if they embolize to the brain. Individual reports of these events are uncommon but may increase with the increased occurrences of their risk factors, for example, intra-arterial procedures.

Method

We searched EMBASE and MEDLINE for articles on embolic stroke of nontissue origin. 1889 articles were identified and screened and 216 articles were ultimately reviewed in full text and included in qualitative analysis. Articles deemed relevant were assessed by a second reviewer to confirm compatibility with the inclusion criteria. References of included articles were reviewed for relevant publications. We categorized the pathology of the emboli into the following groups: air embolism (141 reports), other arterial gas embolisms (49 reports), missiles and foreign bodies (16 reports), and others, including drug embolism, cotton wool, and vascular sclerosant agents.

Conclusion

Air and gaseous embolism are becoming more common with increased use of interventional medical procedures and increased popularity of sports such as diving. There is increasing evidence for the use of hyperbaric oxygen for such events. Causes of solid emboli are diverse. More commonly reported causes include bullets, missiles, and substances used in medical procedures.

Mechanical thrombectomy for repeated cerebral tumor embolism from a thoracic sarcomatoid carcinoma

Cerebral embolism originating from intracardiac tumors represents a rare cause of stroke and has been documented in both adult and pediatric populations. We present a patient recently diagnosed with a right pulmonary hilum tumor, invading the pulmonary veins and the left atrium. Two consecutive episodes of large cerebral vessel occlusion in separate vascular territories occurred in the same day and were treated by mechanical thrombectomy. Embolic material retrieved on both occasions contained tumor fragments with peripheral endothelialization. To our knowledge, this is the first report with histological confirmation of cerebral embolism from an invasive extracardiac tumor.

Thrombectomy for Acute Stroke in Childhood: A Case Report, Literature Review, and Recommendations

The updated American Heart Association/American Stroke Association guidelines include recommendation for thrombectomy in certain adult stroke cases. The safety and efficacy of thrombectomy in children are unknown. An 8-year-old girl experienced acute stroke symptoms on two occasions while therapeutically anticoagulated on Novalung. Computed tomography scans showed proximal vessel thrombi, which were retrieved using a Trevo device without hemorrhagic complications. Postprocedural assessment found respective decreases in the National Institutes of Health Stroke Scale score from 10 to 4 and 12 to 7. The indications for treatment and early benefits observed in our case are consistent with other pediatric thrombectomy cases reported. However, publication bias and the heterogeneity of reported cases prevent drawing conclusions about the safety and efficacy of thrombectomy in children. Anticipating that updates to adult stroke guidelines would likely incite stroke providers to consider thrombectomy in children, our institution developed guidelines for thrombectomy before the index patient. Establishing institutional guidelines before considering thrombectomy in children may optimize patient safety.

Successful Manual Aspiration Thrombectomy in a Pediatric Patient

BACKGROUND

Timely recognition of stroke at major pediatric medical centers is improving, and although treatment guidelines for pediatric stroke exist, no extensive study establishing the efficacy of surgical or thrombolytic treatment has been completed. Extrapolation of adult guidelines to pediatric patients remains the mainstay of treatment in the absence of adequate information regarding safety and efficacy in children. Recent trials have demonstrated revascularization and clinical improvement after endovascular retrieval therapy in adults with acute large vessel occlusive stroke. Furthermore, successful mechanical thrombectomy using a variety of techniques has been documented in numerous children and adolescents.

PATIENT DESCRIPTION

We present a 15-year-old boy with altered mental status and left hemiparesis due to acute ischemic stroke secondary to blockage of the right internal carotid artery terminus, most likely precipitated by end-stage heart failure and cardiac embolism. Mechanical aspiration thrombectomy using the Penumbra aspiration catheter without any adjunct surgical equipment or thrombolytic therapy was used to remove thrombus and treat the patient's acute ischemic stroke. He experienced complete artery recanalization with a Thrombolysis in Cerebral Infarction (TICI) score of 2C after the procedure. He also exhibited an 8 point improvement in his pediatric National Institutes of Health Stroke Scale score within 24 hours.

CONCLUSIONS

Mechanical aspiration thrombectomy is commonly used in adult hospitals but infrequently employed in pediatric patients with arterial ischemic stroke. Given its efficacy in our patient, we encourage a larger systematic trial to evaluate the use of mechanical thrombectomy in pediatric patients with acute ischemic stroke.

Intracranial and visceral arterial embolization of a cardiac myxoma that was treated with endovascular stent-retriever therapy

We report a case of a ruptured left atrial myxoma with multiple synchronous sites of embolization, including the intracranial cerebral (left middle cerebral artery (MCA) and basilar), visceral (renal, superior mesenteric artery (SMA)) and peripheral circulatory beds (aorta and lower extremities). This synchronous embolization resulted in a catastrophic neurologic and systemic event. An intracranial stent retriever was used to restore cerebral circulation in the symptomatic left MCA distribution, which resulted in resolution of the acute neurologic deficits. Endovascular and open surgical interventions were later performed to address the residual cardiac mass and other embolic sites. The patient survived the event with the loss of her right leg below the knee and a transient dialysis requirement. The purpose of this case report is to document the successful utilization of a stent-retriever device in removing an embolized myxoma from the cerebral circulation, to review the unique pathology of this source of embolic stroke and to reiterate the importance of considering embolic and non-thrombotic etiologies of acute ischemic stroke, especially in atypical patient populations and patient presentations.

Mechanical thrombectomy in cardiac myxoma stroke: a case report and review of the literature

Cardiac myxoma is the most common primary tumor of the heart. It is a rare cause of acute ischemic stroke and commonly not detected until after the stroke. There is no current guideline for the treatment of cardiac myxoma stroke and only a few cases of mechanical thrombectomy have been reported. We present a case of cardiac myxoma stroke in a 4-year-old boy treated with a stent-retrieval device and review the literature describing the safety and efficacy of mechanical thrombectomy in cardiac myxoma stroke. We also describe imaging features of the myxoma clot on susceptibility weighted images.

Mechanical thrombectomy in pediatric acute ischemic stroke: Clinical outcomes and literature review

There are limited data on outcomes of mechanical thrombectomy for pediatric stroke using modern devices. In this study, we report two cases of pediatric acute ischemic stroke treated with mechanical thrombectomy, both with good angiographic result (TICI 3) and clinical outcome (no neurological deficits at 90 days). In addition, we conducted a literature review of all previously reported cases describing the use of modern thrombectomy devices. Including our two cases, the aggregate rate of partial or complete vessel recanalization was 100% (22/22), and the aggregate rate of favorable clinical outcome was 91% (20/22). This preliminary evidence suggests that mechanical thrombectomy with modern devices may be a safe and effective treatment option in pediatric patients with acute ischemic stroke.

Considerations in Applying a New Stent Retriever in Pediatric Endovascular Cerebral Thrombectomy for Acute Ischemic Stroke

Acute ischemic stroke (AIS) in children has been difficult to diagnose, treat and study, due to atypical clinical presentation, imaging challenges and the rarity of large-vessel embolic occlusion as the etiology of acute neurological change in children. With endovascular thrombectomy showing success in randomized trials of adult AIS, the technique is increasingly being extrapolated to pediatric stroke. However, there is little evidence regarding the safety or efficacy of applying in children these devices developed and tested in adults. There is concern about a vessel-to-device size mismatch that may result in a different complication and benefit profile than typically seen. We report on the successful application in pediatric stroke of a newer-generation, smaller stent retriever, designed to be delivered through relatively smaller and more navigable microcatheters than the prior generation of this device.

Oncotic Cerebral Aneurysms in a Case of Left Atrial Myxoma, Role of Imaging in Diagnostics and Treatment

BACKGROUND

Myxomatous cerebral (oncotic) aneurysms following atrial myxoma is a rare neurological complication.

CASE REPORT

We report an 11-year- old boy with left atrial myxoma and multiple cerebral oncotic aneurysms. The characteristics of these aneurysms are indefinite and variable. The "Metastasize and Infiltrate" theory may be the key mechanism in the formation of these aneurysms.

CONCLUSIONS

Magnetic resonance imaging (MRI), computed tomography (CT) and angiography are useful in the diagnostics while digital subtraction angiography (DSA) is the best option. There are no definite guidelines for therapy of these aneurysms. Resection of cardiac myxomas, chemotherapy, radiotherapy, coil embolization and surgical treatment could be helpful.

2015 American Heart Association/American Stroke Association Focused Update of the 2013 Guidelines for the Early Management of Patients With Acute Ischemic Stroke Regarding Endovascular Treatment: A Guideline for Healthcare Professionals From the American Heart Association/American Stroke Association

PURPOSE

The aim of this guideline is to provide a focused update of the current recommendations for the endovascular treatment of acute ischemic stroke. When there is overlap, the recommendations made here supersede those of previous guidelines.

METHODS

This focused update analyzes results from 8 randomized, clinical trials of endovascular treatment and other relevant data published since 2013. It is not intended to be a complete literature review from the date of the previous guideline publication but rather to include pivotal new evidence that justifies changes in current recommendations. Members of the writing committee were appointed by the American Heart Association/American Stroke Association Stroke Council's Scientific Statement Oversight Committee and the American Heart Association/American Stroke Association Manuscript Oversight Committee. Strict adherence to the American Heart Association conflict of interest policy was maintained throughout the consensus process. Recommendations follow the American Heart Association/American Stroke Association methods of classifying the level of certainty of the treatment effect and the class of evidence. Prerelease review of the draft guideline was performed by 6 expert peer reviewers and by the members of the Stroke Council Scientific Statement Oversight Committee and Stroke Council Leadership Committee.

RESULTS

Evidence-based guidelines are presented for the selection of patients with acute ischemic stroke for endovascular treatment, for the endovascular procedure, and for systems of care to facilitate endovascular treatment.

CONCLUSIONS

Certain endovascular procedures have been demonstrated to provide clinical benefit in selected patients with acute ischemic stroke. Systems of care should be organized to facilitate the delivery of this care.