Quadrivalvar replacement in infantile Marfan syndrome

High-Throughput Genomics Identify Novel FBN1/2 Variants in Severe Neonatal Marfan Syndrome and Congenital Heart Defects

Fibrillin-1 and fibrillin-2, encoded by FBN1 and FBN2, respectively, play significant roles in elastic fiber assembly, with pathogenic variants causing a diverse group of connective tissue disorders such as Marfan syndrome (MFS) and congenital contractural arachnodactyly (CCD). Different genomic variations may lead to heterogeneous phenotypic features and functional consequences. Recent high-throughput sequencing modalities have allowed detection of novel variants that may guide the care for patients and inform the genetic counseling for their families. We performed clinical phenotyping for two newborn infants with complex congenital heart defects. For genetic investigations, we employed next-generation sequencing strategies including whole-genome Single-Nucleotide Polymorphism (SNP) microarray for infant A with valvular insufficiency, aortic sinus dilatation, hydronephrosis, and dysmorphic features, and Trio whole-exome sequencing (WES) for infant B with dextro-transposition of the great arteries (D-TGA) and both parents. Infant A is a term male with neonatal marfanoid features, left-sided hydronephrosis, and complex congenital heart defects including tricuspid regurgitation, aortic sinus dilatation, patent foramen ovale, patent ductus arteriosus, mitral regurgitation, tricuspid regurgitation, aortic regurgitation, and pulmonary sinus dilatation. He developed severe persistent pulmonary hypertension and worsening acute hypercapnic hypoxemic respiratory failure, and subsequently expired on day of life (DOL) 10 after compassionate extubation. Cytogenomic whole-genome SNP microarray analysis revealed a deletion within the FBN1 gene spanning exons 7-30, which overlapped with the exon deletion hotspot region associated with neonatal Marfan syndrome. Infant B is a term male prenatally diagnosed with isolated D-TGA. He required balloon atrial septostomy on DOL 0 and subsequent atrial switch operation, atrial septal defect repair, and patent ductus arteriosus ligation on DOL 5. Trio-WES revealed compound heterozygous c.518C>T and c.8230T>G variants in the FBN2 gene. Zygosity analysis confirmed each of the variants was inherited from one of the parents who were healthy heterozygous carriers. Since his cardiac repair at birth, he has been growing and developing well without any further hospitalization. Our study highlights novel FBN1/FBN2 variants and signifies the phenotype-genotype association in two infants affected with complex congenital heart defects with and without dysmorphic features. These findings speak to the importance of next-generation high-throughput genomics for novel variant detection and the phenotypic variability associated with FBN1/FBN2 variants, particularly in the neonatal period, which may significantly impact clinical care and family counseling.

Heart transplantation in neonatal Marfan syndrome: Saving life in a rare and fatal condition

BACKGROUND

Neonatal Marfan syndrome is a rare disease with mortality in the first year of life reported as high as 95% predominantly due to progressive heart failure from valvar regurgitation and cardiomyopathy. Multisystem involvement and uncertain prognosis have historically precluded transplant candidacy, and current management options are of limited success.

CASE REPORT

We present a baby girl with a postnatal diagnosis of neonatal Marfan syndrome who at 1 year of age underwent mitral valve and tricuspid valve repair with postoperative profound left ventricular and moderate right ventricular dysfunction necessitating biventricular assist device (BiVAD) support and subsequent heart transplant. A number of noncardiac issues persisted in our patient; however, she enjoyed a good quality of life for the initial 3 years posttransplant. Unfortunately, she subsequently developed rapidly progressive coronary allograft vasculopathy (CAV) with progressive deterioration in function and cardiac arrest.

CONCLUSION

To our best knowledge, this is only the second case of neonatal Marfan syndrome to undergo heart transplant reported in the literature and the first with BiVAD support as a bridge to candidacy. This is also the first case of neonatal Marfan syndrome associated with intragenic duplication. This case though demonstrating that earlier listing, ventricular assist device (VAD) support and even primary transplant as treatment in neonatal Marfan syndrome should all be considered viable options but also portends a cautionary tale given the spectrum of comorbidities in this rare and severe disorder.

Early Onset Marfan Syndrome with multivalvular insufficiency: Report from a tertiary hospital in Tanzania, and a review of the recurrent c.7606G>A p.0 variant in FBN1

Marfan Syndrome is an autosomal dominant connective tissue disorder caused by mutations in the FBN1 gene. Early Onset Marfan Syndrome is at the severe end of the Marfan syndrome spectrum and is frequently associated with variants in exons 24-32 of the FBN1 gene. To the best of our knowledge, this is the first molecularly confirmed patient from Sub-Saharan Africa with Early Onset Marfan Syndrome who presented with tall stature, arachnodactyly, multivalvular insufficiency and ectopia lentis. Sequencing analysis of FBN1 gene revealed a pathogenic (class 5) heterozygous recurrent variant in exon 61 (c.7606G > A p.0NM_000138.3), which was up to now not associated with rapidly progressive Marfan syndrome with multivalvular insufficiency and congestive cardiac failure. This further supports the notion that the interplay of the given FBN1 mutation, one or more genetic modifiers and epigenetic and environmental factors defines the disease phenotype.

Neonatal Marfan syndrome with missense variant of c.3706T>C undergoing bilateral atrioventricular valve replacement

Neonatal Marfan syndrome is a rare condition with poor prognosis because of severe mitral and/or tricuspid valve insufficiency. Mitral valve replacement is sometimes required in early infancy, while tricuspid valve replacement is rarely done. We report the first infant neonatal Marfan syndrome case with a missense variant of c.3706T>C in the fibrillin-1 gene that was successfully managed by mitral and tricuspid valve replacement. Early multiple-valve replacement may sometimes be required during infant age in this genetic syndrome.

Severe phenotypes of B3GAT3-related disorder caused by two heterozygous variants: a case report and literature review

Background

Linkeropathies refers to a series of extremely rare hereditary connective tissue diseases affected by various glycosyltransferases in the biosynthesis of proteoglycans. We report for the first time two heterozygous variants of B3GAT3 in a Chinese infant, in whom Marfan syndrome was suspected at birth.

Case presentation

A 2-month-old boy from a non-consanguineous Chinese family without a family history presented severe phenotypes of joint dislocation, obvious flexion contractures of the elbow, arachnodactyly with slightly adducted thumbs, cranial dysplasia, foot abnormalities and aortic root dilation; Marfan syndrome was suspected at birth. Our patient was the youngest, at the age of 2 months, to experience aortic root dilation. Two B3GAT3 variants, NM_012200.2, c.752T>C, p.V251A and c.47C>A, p.S16*, with heterozygosity were identified in the patient by whole-exome sequencing; the variants were inherited from his parents. During close follow-up, significant changes in the cranial profile and obvious external hydrocephalus were present at the age of 7 months, which differs from previously reported cases.

Conclusion

We diagnosed a patient with congenital heart defects at an early age with a B3GAT3-related disorder instead of Marfan syndrome and expanded the spectrum of B3GAT3-related disorders. We also provide a literature review of reported B3GAT3 cases; for at least one of the variants, this is the first report of genotype–phenotype correlations in individuals with cardiovascular defects being related to the acceptor substrate-binding subdomain of B3GAT3.

A Novel Case of Marfan Syndrome in an Infant With Hypoplastic Left Heart Syndrome

This report describes a case of hypoplastic left heart syndrome (HLHS) and Marfan syndrome presenting in conjunction, and highlights how a connective tissue disorder may alter medical and surgical management of newborns with HLHS.

Microcornea and bilateral ectopia lentis in an infant: unusual severe ocular presentation of neonatal Marfan syndrome

We present an unusual case of microcornea, bilateral spontaneous dislocation of lenses, and anomalous optic disks in a 7-week-old girl in whom a systemic diagnosis of Marfan syndrome had not yet been confirmed at presentation. The causes and differential diagnoses of this condition are discussed, and the literature on ocular manifestations of neonatal Marfan syndrome is reviewed.

Early-Onset Marfan Syndrome: A Case Series

Mutations in fibrillin 1 cause Marfan syndrome (MFS), an autosomal dominant disorder of the connective tissue, with multisystem manifestations. In early-onset MFS, the physical characteristics are expressed much earlier than the classical MFS. Those affected by this form generally have their mutations restricted to the gene "hotspot" region of exons 24 to 32. Historically, affected individuals usually die within the first few years of life due to heart failure secondary to severe valvular insufficiency. We report three patients with early-onset MFS, whose clinical evolution has been remarkably positive, when compared with other reported cases in the literature.

Palliative Mitral Valve Repair During Infancy for Neonatal Marfan Syndrome

An infant with neonatal Marfan syndrome (nMFS), a condition that is nearly always lethal during infancy, was referred to our hospital with symptoms of congestive heart failure resulting from severe mitral valve insufficiency. During mitral valve repair, the use of an annuloplasty ring was waived until annular dilatation was achieved after 2 palliative mitral valvuloplasty procedures. After the definitive operation, the patient's mitral valve function remained within normal limits until the last follow-up when the patient was 11 years old. To the best of our knowledge, this patient has the longest recorded survival after mitral valve repair.

A Case of Neonatal Marfan Syndrome: A Management Conundrum and the Role of a Multidisciplinary Team

Neonatal Marfan syndrome (nMFS) is a rare condition with a poor prognosis. It is genotypically and phenotypically distinct from the typical Marfan syndrome and carries a poorer prognosis. This case report describes the progression of a 14-month-old girl diagnosed with nMFS at 5 months of age. Her diagnosis followed the identification of a fibrillin-1 mutation (FBN1 gene, exon 26, chromosome 15), which is a common locus of nMFS. This patient developed severe cardiac complications resulting in congestive cardiac failure in early life and required major cardiac surgery. Since surgical intervention, our patient is still reliant on a degree of ventilator support, but the patient has gained weight and echocardiography has demonstrated improved left ventricular function and improved tricuspid and mitral valve regurgitation. Therefore, we argue the importance of a cautious multidisciplinary approach to early surgical intervention in cases of nMFS.

A novel fibrillin-1 gene missense mutation associated with neonatal Marfan syndrome: a case report and review of the mutation spectrum

BACKGROUND

Marfan syndrome (MFS) is a heritable disorder of connective tissue resulting from pathogenic variants of the fibrillin-1 gene (FBN1). Neonatal Marfan syndrome (nMFS) is rare and the most severe form of MFS, involving rapidly progressive cardiovascular dysfunction leading to death during early childhood. The constant enrichment of the nMFS mutation spectrum is helpful to improve our understanding of genotype-phenotype correlations in the disease. Herein, we report a novel dominant mutation in exon 26 of FBN1 (c.3331 T > C) in a sporadic case with nMFS.

CASE PRESENTATION

An 8-month-old Han Chinese girl presented with the classic nMFS phenotype, including prominent manifestations of bone overgrowth, aortic root dilatation, and multiple cardiac valve dysfunctions. Genetic analysis revealed that she was heterozygous for a de novo FBN1 missense mutation (c.3331 T > C). The mutation leads to the substitution of a highly conserved FBN1 cysteine residue (p.Cys1111Arg), which is likely to severely perturb the FBN1 structure because of an alteration of the disulfide bond pattern in the calcium-binding epidermal growth factor-like (cbEGF) 12 domain. This variant was absent in 208 ethnically matched controls, providing further evidence that it may be causative of nMFS. An analysis of nMFS-associated mutations from the UMD-FBN1 database indicates that those de novo mutations altering disulfide bonds or Ca(2+) binding sites of the cbEGF domains encoded by exons 25-33, and a lack of phenotypic heterogeneity may be associated with an increased risk for nMFS.

CONCLUSION

We diagnosed an infant with rare nMFS showing rapidly progressive cardiovascular dysfunction and widely systemic features. As the only causal FBN1 mutation identified in the patient, the missense mutation c.3331 T > C (p.Cys1111Arg) was associated with the severe phenotype of MFS. However, the pathogenicity of the novel mutation needs further confirmation in other patients with nMFS. Our review of the prominent characteristics of nMFS mutations relative to classic or incomplete MFS-related mutations will be helpful for the recognition of novel nMFS-associated variants.

Infantile Marfan syndrome in a Korean tertiary referral center

Purpose

Infantile Marfan syndrome (MFS) is a rare congenital inheritable connective tissue disorder with poor prognosis. This study aimed to evaluate the cardiovascular manifestations and overall prognosis of infantile MFS diagnosed in a tertiary referral center in Korea.

Methods

Eight patients diagnosed with infantile MFS between 2004 and 2014 were retrospectively evaluated.

Results

Their median age at the time of diagnosis was 2.5 months (range, 0–20 months). The median follow-up period was 25.5 months (range, 0–94 months). The median length at birth was 50.0 cm (range, 48–53 cm); however, height became more prominent over time, and the patients were taller than the 97th percentile at the time of the study. None of the patients had any relevant family history. Four of the 5 patients who underwent DNA sequencing had a fibrillin 1 gene mutation. All the patients with echocardiographic data of the aortic root had a z score of >2. All had mitral and tricuspid valve prolapse, and various degrees of mitral and tricuspid regurgitation. Five patients underwent open-heart surgery, including mitral valve replacement, of whom two required multiple operations. The median age at mitral valve replacement was 28.5 months (range, 5–69 months). Seven patients showed congestive heart failure before surgery or during follow-up, and required multiple anti-heart failure medications. Four patients died of heart failure at a median age of 12 months.

Conclusion

The prognosis of infantile MFS is poor; thus, early diagnosis and timely cautious treatment are essential to prevent further morbidity and mortality.

CHD associated with syndromic diagnoses: peri-operative risk factors and early outcomes

CHD is frequently associated with a genetic syndrome. These syndromes often present specific cardiovascular and non-cardiovascular co-morbidities that confer significant peri-operative risks affecting multiple organ systems. Although surgical outcomes have improved over time, these co-morbidities continue to contribute substantially to poor peri-operative mortality and morbidity outcomes. Peri-operative morbidity may have long-standing ramifications on neurodevelopment and overall health. Recognising the cardiovascular and non-cardiovascular risks associated with specific syndromic diagnoses will facilitate expectant management, early detection of clinical problems, and improved outcomes--for example, the development of syndrome-based protocols for peri-operative evaluation and prophylactic actions may improve outcomes for the more frequently encountered syndromes such as 22q11 deletion syndrome.

Early onset marfan syndrome: Atypical clinical presentation of two cases

Early onset Marfan Syndrome (eoMFS) is a rare, severe form of Marfan Syndrome (MFS). The disease has a poor prognosis and most patients present with resistance to heart failure treatment during the newborn period. This report presents two cases of eoMFS with similar clinical features diagnosed in the newborn period and who died at an early age due to the complications related to the involvement of the cardiovascular system.

Aortic Involvement in Pediatric Marfan syndrome: A Review

Outlining specific protocols for the management of pediatric patients with Marfan syndrome has been challenging. This is mostly due to a dearth of clinical studies performed in pediatric patients. In Marfan syndrome, the major sources of morbidity and mortality relate to the cardiovascular system. In this review, we focus on aortic involvement seen in pediatric patients with Marfan syndrome, ranging from aortic dilatation to aortic rupture and heart failure. We discuss the histological, morphological, and pathogenetic basis of the cardiac manifestations seen in pediatric Marfan syndrome and use a specific case to depict our experienced range of cardiovascular manifestations. The survival for patients with Marfan syndrome may approach the expected survival for non-affected patients, with optimal management. With this potentiality in mind, we explore possible and actual management considerations for pediatric Marfan syndrome, examining both medical and surgical therapy modalities that can make the possibility of improved survival a reality.