Rapid de novo aneurysm formation after clipping of a ruptured middle cerebral artery aneurysm in an infant with an MYH11 mutation

Early Onset Parkinson Syndrome, Type A Aortic Aneurysm and Noncompaction Associated With the Novel Variant c.2225C>T in MYH11: A Case Report

Aortic aneurysm, left ventricular noncompaction, and early onset Parkinson syndrome have not been reported in association with MYH11 variants. The patient is a 44-year-old male who developed a progressive ascending aortic aneurysm at age 30, requiring aortic repair at the age of 40. In addition, he developed Parkinson syndrome at the age of 37. He also suffered from myopia, hypothyroidism, arterial hypertension, hyperlipidemia, pre-diabetes, hyperbilirubinemia, obstructive sleep apnea syndrome (OSAS), and muscle cramps. Echocardiography and cardiac MRI showed left ventricular noncompaction. Genetic analysis revealed the novel heterozygous variant c.2225C>T (p.Ala742Val) in MYH11. Family history was positive for arterial hypertension (mother), carcinoma (brother), and diabetes (sister, father). There was consanguinity between the parents. With appropriate treatment, Parkinson syndrome and cardiac anomalies remained stable and there were no complications due to noncompaction or aortic repair. Considering that embryonic vascularisation may be involved in the pathophysiology of noncompaction and that MYH11 is expressed in the myocardium, a causal relationship between the MYH11 variant and noncompaction is conceivable. In conclusion, this is the first case showing an aortic aneurysm associated with noncompaction and Parkinson syndrome in a carrier of the novel, heterozygous variant c.2225C>T in MYH11. Carriers of MYH11 variants should be prospectively and systematically screened for multisystem diseases as soon as the genetic defect is discovered in order not to delay any necessary treatment. First-degree relatives should be screened for the MYH11 variant of a family member to track the trait of inheritance and confirm its pathogenicity.

Genome-wide identification and phenotypic characterization of seizure-associated copy number variations in 741,075 individuals

Copy number variants (CNV) are established risk factors for neurodevelopmental disorders with seizures or epilepsy. With the hypothesis that seizure disorders share genetic risk factors, we pooled CNV data from 10,590 individuals with seizure disorders, 16,109 individuals with clinically validated epilepsy, and 492,324 population controls and identified 25 genome-wide significant loci, 22 of which are novel for seizure disorders, such as deletions at 1p36.33, 1q44, 2p21-p16.3, 3q29, 8p23.3-p23.2, 9p24.3, 10q26.3, 15q11.2, 15q12-q13.1, 16p12.2, 17q21.31, duplications at 2q13, 9q34.3, 16p13.3, 17q12, 19p13.3, 20q13.33, and reciprocal CNVs at 16p11.2, and 22q11.21. Using genetic data from additional 248,751 individuals with 23 neuropsychiatric phenotypes, we explored the pleiotropy of these 25 loci. Finally, in a subset of individuals with epilepsy and detailed clinical data available, we performed phenome-wide association analyses between individual CNVs and clinical annotations categorized through the Human Phenotype Ontology (HPO). For six CNVs, we identified 19 significant associations with specific HPO terms and generated, for all CNVs, phenotype signatures across 17 clinical categories relevant for epileptologists. This is the most comprehensive investigation of CNVs in epilepsy and related seizure disorders, with potential implications for clinical practice.

Ruptured Middle Cerebral Artery Aneurysm in an Infant: Case Report and Literature Review

Intracranial aneurysms (IA) in infants are reportedly rare at 0.5% to 4.5% of all aneurysms. Furthermore, subarachnoid hemorrhage in infants younger than three months are even rarer as it has been reported in approximately 20 cases only till date. A 3-month-old infant with seizures and impaired consciousness was admitted to our hospital. Three-dimensional computed tomography angiography (3D-CTA) revealed a dissecting aneurysm with a maximum diameter of 13 mm in the right M2. Internal trapping using detachable coil were successfully performed, following which he was discharged without significant neurological deficit after one month of onset. Thus, we have reported a rare case of a large ruptured dissecting IA in a 3-month-old infant, in the right middle cerebral artery (MCA), successfully treated with an endovascular therapy, along with a literature review.

Vascular smooth muscle cells in intracranial aneurysms

Intracranial aneurysm (IA) is a severe cerebrovascular disease characterized by abnormal bulging of cerebral vessels that may rupture and cause a stroke. The expansion of the aneurysm accompanies by the remodeling of vascular matrix. It is well-known that vascular remodeling is a process of synthesis and degradation of extracellular matrix (ECM), which is highly dependent on the phenotype of vascular smooth muscle cells (VSMCs). The phenotypic switching of VSMC is considered to be bidirectional, including the physiological contractile phenotype and alternative synthetic phenotype in response to injury. There is increasing evidence indicating that VSMCs have the ability to switch to various phenotypes, including pro-inflammatory, macrophagic, osteogenic, foamy and mesenchymal phenotypes. Although the mechanisms of VSMC phenotype switching are still being explored, it is becoming clear that phenotype switching of VSMCs plays an essential role in IA formation, progression, and rupture. This review summarized the various phenotypes and functions of VSMCs associated with IA pathology. The possible influencing factors and potential molecular mechanisms of the VSMC phenotype switching were further discussed. Understanding how phenotype switching of VSMC contributed to the pathogenesis of unruptured IAs can bring new preventative and therapeutic strategies for IA.

Ruptured AComA aneurysm and asymptomatic bilateral ACA vasospasm in an infant: surgical case report

Intracranial aneurysms (IAs) are localized dilations of the cerebral vasculature, representing the leading cause for non-traumatic subarachnoid hemorrhage and an important source of morbidity and mortality. Despite it being a frequent pathology and most often diagnosed incidentally, IAs in infants are a very rare occurrence, and the ruptured variant is exceptional. A 4-month-old boy with a negative family history was brought to our department because of several episodes of incoercible vomiting and fever. Upon examination, the child was somnolent, without any noticeable deficit. Transfontanellar ultrasonography and CT angiography revealed a ruptured aneurysm of the anterior communicating artery (AComA), whereas the pre-clipping MRI showed thin, almost angiographically invisible anterior cerebral arteries (ACAs) on both sides due to vasospasm. We intervened surgically by placing an external ventricular shunt in an emergency setting, followed by clipping of the IA in a delayed manner. The child was discharged a month after admission with no deficit, despite the paradoxical aspect of the ACA. Ruptured IAs can be safely treated via microsurgery, even in infants. However, this requires a great amount of experience and surgical expertise. Furthermore, the lack of proper management would most likely result in a severe deficit in the long term. Lastly, the lack of visibility of the ACA on angiographic studies may not have neurological consequences if they occur in this age group.

Pathogenic Factors and Prognosis of De Novo Aneurysms vAfter Aneurysm Clipping

OBJECTIVE

To confirm this hypothesis, this study aimed to explore the pathogenic factors, prognosis, and their relationship in de novo aneurysms and to reach a consensus on their management.

METHODS

First, the clinical data of 5 patients with de novo aneurysms from April 1998 to October 2021 were analyzed retrospectively. Then, the English literature on de novo aneurysms reported in Pubmed from 1985 to 2021 was systematically reviewed, and 18 case reports from 17 articles and 16 case series were identified. Univariate and multivariate analyses and modified Fisher test were used to analyze the relationship between pathogenic factors and prognosis.

RESULTS

Hypertension was noted in 60% of our clinical cases, 50% of the case series identified in the literature review, and 66.7% of the case reports in the literature review. In the case reports identified from our literature review, the proportion of original aneurysms in the anterior circulation was 96.3%. Moreover, in our 5 cases, all original aneurysms occurred in the anterior circulation. The rupture rate of original aneurysms in our 5 cases was 100%, and that of the cases reported in the literature review was 88.9%. Univariate logistic analysis showed that the time interval was related to the prognosis of de novo aneurysms with a P value of 0.048 and an odds ratio of 0.968 (95% confidence interval 0.938-1.000). Modified Fisher exact tests showed that patient age at the occurrence of de novo aneurysm P = 0.029) was related to the prognosis of de novo aneurysms.

CONCLUSIONS

Hypertension, an original aneurysms located in the anterior circulation and rupture represent the pathogenic factors associated with de novo aneurysms. The time interval to de novo aneurysm and patient age at the occurrence of de novo aneurysm are predictive of prognosis. Based on the above information, we can prevent and improve the prognosis of de novo aneurysms.

Rescue endovascular treatment for rapid regrowth of aneurysm remnant on middle cerebral artery trunk after unsuccessful surgical clipping in patients with a ruptured cerebral aneurysm: A report of two cases

We report two rare cases treated with coiling after rapid regrowth (within a month) of an aneurysm remnant on the middle cerebral artery (MCA) trunk after incomplete surgical clipping. The first case, a 47-year-old man with subarachonoid hemorrhage (SAH) (Hunt-Hess grade II, Fisher grade III) underwent clipping of a ruptured saccular aneurysm with a wide neck on the right early frontal branch arising from the MCA trunk. Incomplete clipping with a 1 mm sized remnant neck was performed to avoid sacrificing the lenticulostriate artery. In a follow-up cerebral angiogram on postoperative day 30, a rapid regrowth of the aneurysm remnant was observed, and on that day, complete obliteration was obtained by rescue endovascular treatment. The second case, a 48-year-old healthy woman with SAH (Hunt-Hess grade II, Fisher grade III) underwent clipping of an anteroposteriorly projecting bilobulated aneurysm on the left M1. Incomplete clipping with a minimal remnant neck was performed. In follow-up digital subtraction angiogram on postoperative day 30, a rapid regrowth of an aneurysm remnant involving only a part of the initial aneurysm near the neck was observed, and on that day, complete obliteration was obtained by rescue coiling. These patients were both discharged without any neurological deficits.

Endovascular treatment of intracranial vascular malformations in children

Paediatric intracranial vascular malformations are rare and different from adult ones in vascular anatomy, pathophysiology, and symptoms. Their impact on the brain and their symptoms will differ in the antenatal period, in neonates, infants, and children. Clinical presentation includes seizures, focal neurological deficit, haemorrhage, congestive heart failure, hydrovenous disorder, and developmental delays. These malformations are thus associated with a poor prognosis if left untreated. Therefore, aggressive management is generally recommended and must be performed by a multidisciplinary team with extensive experience. Endovascular treatment is the first-choice treatment for most paediatric intracranial vascular malformations. Indication and timing for treatment should be decided on the basis of a careful assessment of neurological symptoms, growth and development, cardiac and other systemic manifestations, and imaging of the malformation and the brain tissue. WHAT THIS PAPER ADDS: Paediatric intracranial vascular malformations are rare, but their prognosis is poor if left untreated. Improved clinical, anatomical, and pathophysiological understanding of these complex lesions has improved prognosis.

Intracranial Vessel Stenosis in a Young Patient with an MYH11 Mutation: A Case Report and Review of 2 Prior Cases

BACKGROUND

The MYH11 gene codes for smooth muscle myosin heavy chain, which has a critical function in maintaining vascular wall stability. Patients with this mutation most commonly have aortic and cardiac defects. Documented involvement of intracranial vessels is exceptional.

CASE DESCRIPTION

A 29-year-old woman with a history of patent ductus arteriosus and aortic dissection was found to have incidental bilateral stenosis of the terminal internal carotid arteries as well as the proximal anterior cerebral arteries, middle cerebral arteries, and posterior cerebral arteries on magnetic resonance angiography that was obtained for unrelated symptoms. There was no evidence of basal collateral formation, and a generalized straightening of the vessels was observed. These angiographic findings have been typically observed in patients with ACTA2 mutations. Thus, genetic testing was pursued, which uncovered the presence of an MYH11 mutation. Follow-up imaging at 51 months demonstrated that the intracranial stenosis remained stable without evidence of basal collateral formation. She did not experience any neurologic events during the follow-up interval.

CONCLUSIONS

Intracranial vessel involvement in patients with MYH11 mutations is rare. Vigilant cerebrovascular monitoring should be practiced in this population to guide appropriate management. Reporting of similar cases is important to improve understanding of the development of idiopathic intracranial stenosis in young individuals.

Genetics of syndromic and nonsyndromic aortopathies

PURPOSE OF REVIEW

To review the literature and provide a summary of management of syndromic and nonsyndromic aortopathies.

RECENT FINDINGS

The number of newly identified genetic causes for aortopathies have continued to increase over the past 10 years. The number of reported individuals with most hereditary aneurysm genes is small but increasing with more publications focusing describing the natural history caused by each gene.

SUMMARY

Aortopathy can present as an isolated finding or present as part of a larger genetic syndrome. Advances in genetic testing technology has shed light on the increasing importance of molecular diagnostics in the evaluation and management of patients with hereditary aortic disease. Molecular diagnostics and family phenotyping can aide in the diagnosis and management of pediatric patients with aortic disease.

Genetic Profiles Related to Pathogenesis in Sporadic Intracranial Aneurysm Patients

BACKGROUND

Intracranial aneurysm (IA) represents a cerebrovascular disorder that featured by dilation or bulging of the weakened blood vessel wall. When it ruptures, an IA leads to subarachnoid hemorrhage with high disability and mortality rates. Despite the numerous studies focusing on IA ruptures, little research on IA pathogenesis has been reported. In this study, we aimed to reveal key genes related to IA formation.

METHODS

Four datasets from Gene Expression Omnibus data were downloaded, normalized, and separated into the IA group and the normal vessel control group for analyses. We screened for differentially expressed genes (DEGs) between groups and conducted functional enrichment, pathway enrichment, and gene set enrichment analysis analyses among significant DEGs.

RESULTS

according to our analyses, significant DEGs majorly associate with smooth muscle system and the complement system. Among all DEGs, 5 down-regulated genes (MYH11, CNN1, MYOCD, ACTA1, and LMOD1) and 3 up-regulated genes (C1QB, C3AR1, and VSIG4) are most relevant in IA formation.

CONCLUSIONS

Key DEGs identified in this study are related to IA pathogenesis. Among identified DEGs, LMOD1 is the most significant and merits more attention.

Smooth muscle cells of intracranial vessels: from development to disease

Cerebrovascular diseases that cause ischaemic or haemorrhagic stroke with subsequent loss of life or functional capacity due to damage of the brain tissue are among the leading causes of human suffering and economic burden inflicted by diseases in the developed world. Diseases affecting intracranial vessels are significant contributors to ischaemic and haemorrhagic strokes. Brain arteriovenous malformations, which are a collection of abnormal blood vessels connecting arteries to veins, are the most common cause of intracranial haemorrhage in children and young adults. Saccular intracranial aneurysms, which are pathological saccular dilations mainly occurring at bifurcations of the large intracranial arteries near the circle of Willis, are highly prevalent in the middle-aged population, causing significant anxiety and concern; their rupture, although rare, is a significant cause of intracranial haemorrhage in those past middle age that is associated with a very sinister prognosis. Cerebral small-vessel disease, which comprise all pathological processes affecting vessels <500 microns in diameter, account for the majority of intracerebral haemorrhages and ∼25% of ischaemic strokes and 45% of dementias in the elderly. In this review, we summarize the developmental, structural, and functional features of intracranial vessels. We then describe the role of smooth muscle cells in brain arteriovenous malformations, intracranial aneurysms, and small-vessel diseases, and discuss how the peculiar ontogeny, structure, and function of intracranial vessels are related to the development of these diseases.

Intracranial Aneurysms: Pathology, Genetics, and Molecular Mechanisms

Intracranial aneurysms (IA) are local dilatations in cerebral arteries that predominantly affect the circle of Willis. Occurring in approximately 2-5% of adults, these weakened areas are susceptible to rupture, leading to subarachnoid hemorrhage (SAH), a type of hemorrhagic stroke. Due to its early age of onset and poor prognosis, SAH accounts for > 25% of years lost for all stroke victims under the age of 65. In this review, we describe the cerebrovascular pathology associated with intracranial aneurysms. To understand IA genetics, we summarize syndromes with elevated incidence, genome-wide association studies (GWAS), whole exome studies on IA-affected families, and recent research that established definitive roles for Thsd1 (Thrombospondin Type 1 Domain Containing Protein 1) and Sox17 (SRY-box 17) in IA using genetically engineered mouse models. Lastly, we discuss the underlying molecular mechanisms of IA, including defects in vascular endothelial and smooth muscle cells caused by dysfunction in mechanotransduction, Thsd1/FAK (Focal Adhesion Kinase) signaling, and the Transforming Growth Factor β (TGF-β) pathway. As illustrated by THSD1 research, cell adhesion may play a significant role in IA.

Pediatric intracranial aneurysms: changes from previous studies

PURPOSE

To develop a better understanding of pediatric intracranial aneurysms (PIAs).

METHODS

All PIAs treated in our center from January 2012 to April 2017 were retrospectively included. Clinical data, treatment summaries, and follow-up outcomes were retrieved and analyzed.

RESULTS

A total of 66 PIAs were found in 64 patients with a mean age of 11.4 ± 5.7 years, 68.8% of whom were male. The most common symptoms were seizure (n = 7, 63.6%) for the 0-5 age group and headache (n = 38, 71.7%) for the 6-18 age group. Fifty-one PIAs (77.3%) were located in the anterior circulation, with the middle cerebral artery (MCA) being the most common site (n = 28, 42.4%). Fifteen patients (23.4%) had PIAs that were pseudoaneurysms, and nine of them (60%) had a combined history of head trauma. Thirty-five patients (54.7%) had distal arterial aneurysms, and 21 of them (60%) presented with seizure. During a mean follow-up time of 1.6 ± 1.2 years, 79.7% of patients (n = 51) had favorable outcomes, 5 patients (7.8%) died, and the remaining 8 patients (12.5%) had unfavorable outcomes with severe neurological deficits.

CONCLUSION

Apart from characteristics consistent with previous studies, several new findings regarding PIAs were reported, including a difference in the most common symptoms in different age groups, the MCA as the predominant location of PIAs, the high ratio of pseudoaneurysms and their head trauma etiology, and the incidence of distal arterial aneurysms and their relationship with the risk of seizures.

Radiologic Characteristics and High Risk of Seizures in Infants with Ruptured Intracranial Aneurysms: Case Report and Review of the Literature

OBJECTIVE

To evaluate the parameters related to the high risk of preoperative seizures in infants (1 year or younger) with ruptured intracranial aneurysms.

METHODS

Infants with ruptured intracranial aneurysms treated at our institution from January 2012 to January 2018 were retrospectively analyzed. Seventeen similar cases of infant patients with seizures reported in published studies were reviewed.

RESULTS

The mean age of the 7 infant patients treated at our institution was 4.1 ± 3.3 months (range, 28 days to 11 months), with 2 male and 5 female subjects. One patient (14.3%) had an internal carotid artery aneurysm with subarachnoid hemorrhage, and the remaining 6 patients (85.7%) had middle cerebral artery (MCA) aneurysms in the distal arterial region with lobe hemorrhage. Five of the 7 infants (71.4%) had seizures, 4 of whom (4/5, 80.0%) had MCA distal arterial aneurysms with lobe hemorrhage. Management was successful for all patients with aneurysm clipping or resection surgery, and one patient experienced postoperative seizures. Of the 17 reviewed cases of infant patients with seizures, 10 patients (58.8%) exhibited the typical distal arterial aneurysm with lobe hemorrhaging, and 6 (60%) of them had aneurysms in MCA.

CONCLUSIONS

Infant patients with ruptured intracranial aneurysms have a high risk of preoperative seizures. The typical radiologic finding of distal arterial aneurysm with lobe hemorrhage was frequently observed in the MCA, and it might be related to the high risk of preoperative seizures in this population. Microsurgical techniques effectively control postoperative seizures in infants with ruptured intracranial aneurysms.

Successful microsurgical treatment of intracranial aneurysms in infants: a retrospective study and literature review

OBJECTIVE

Intracranial aneurysms are extremely rare in infants, especially less than 1 year old. This study aimed to analyze the frequency of infantile intracranial aneurysm in our department and investigate the clinical characteristics, treatment strategies, and outcomes of this disease.

METHODS

Six infants under 1 year old in 4350 patients with intracranial aneurysms were retrospectively analyzed from January 2010 to December 2016.

RESULTS

The patients (5 females and 1 male) ranged in age from 2 to 11 (mean age, 4.67) months. Four patients presented with generalized seizure and vomiting, 3 showed lethargy, 1 presented eye deviation, and 1 had right-sided hemiparesis. Radiographically, two aneurysms were localized in the middle cerebral artery (MCA) of the M2 segment, two were located in the M3 segment of MCA, one was located at left MCA bifurcation, and one was located at the nonbranching site of the left supraclinoid internal carotid artery. All these lesions were successfully managed with aneurysm clipping or resection, and the improvement of neurological deficits was achieved in all patients.

CONCLUSION

Intracranial aneurysms should be considered in the differential diagnosis of infants who present with acute raised intracranial pressure. An improvement of neurological deficits is noted in infants who are managed promptly with microsurgical techniques of clipping during the long-term follow-up.

Lethal Ultra-Early Subarachnoid Hemorrhage Due to Rupture of De Novo Aneurysm 5 Months After Primary Aneurysmatic Subarachnoid Hemorrhage

BACKGROUND

Approximately 1% of all patients surviving rupture of a cerebral aneurysm suffer from a second aneurysmatic subarachnoid hemorrhage later in their lives, 61% of which are caused by rupture of a de novo aneurysm. Latency between bleedings is usually many years, and younger patients tend to achieve better outcomes from a second subarachnoid hemorrhage.

CASE DESCRIPTION

We report an unusual case of lethal ultra-early rupture of a de novo aneurysm of the anterior communicating artery only 5 months after the initial subarachnoid hemorrhage and complete coiling in a young, healthy male patient.

CONCLUSION

Despite complete aneurysm obliteration, young age, and good recovery, patients may be subjected to secondary subarachnoid hemorrhages from de novo aneurysms after only a few months of the initial bleeding. Early-control magnetic resonance angiography might hence be advisable.

Identification of key genes, transcription factors and microRNAs involved in intracranial aneurysm

Intracranial aneurysm (IA) is a devastating disease, the pathogenesis of which remains to be elucidated. The present study aimed to determine the molecular mechanism of IA and to identify potential therapeutic targets using bioinformatics analysis. The GSE54083 dataset, which includes data from patients with ruptured IA and superficial temporal artery controls, was downloaded from the Gene Expression Omnibus, and differentially expressed genes (DEGs) were identified in the ruptured IA samples using the limma package in R. Subsequently, the Database for Annotation, Visualization and Integrated Discovery software was used to perform function and pathway enrichment analyses and the Search Tool for the Retrieval of Interacting Genes database was used to construct the protein‑protein interaction (PPI) network. Then, microRNA (miRNA) target and transcription factor (TF) target pairs were identified using the miR2Disease, MiRwalk2, ITFP and TRANSFAC databases. Finally, an integrated network of TF‑target‑miRNAs was constructed using Cytoscape. A total of 402 upregulated DEGs and 375 downregulated DEGs were identified from the ruptured IA samples compared with the superficial temporal artery samples. The majority of the upregulated DEGs were significantly enriched in the immune system development category, including CD40 ligand (CD40LG) and CD40 and the downregulated DEGs, such as striatin (STRN), were enriched in neuron projection development. In addition, nitric oxide synthase 1 (NOS1), a target of miRNA‑125b, and myosin heavy chain 11 (MYH11), a target of minichromosome maintenance complex component 4 (MCM4), had higher degree scores in the integrated network. These findings suggest that CD40, CD40LG, NOS1, STRN, MCM4, MYH11 and miR‑125b may be potential therapeutic targets for the treatment of IA.