Multimodality imaging in diagnosing lipomatous atrial septal hypertrophy with atrial septal defect: a case report.

Background: Lipomatous atrial septal hypertrophy (LASH) with atrial septal defect (ASD) is a rare congenital anomaly. Although LASH is a histologically benign cardiac lesion characterized by excessive fat deposition in the interatrial septum that spares the fossa ovale, it has been associated with supraventricular arrhythmias or sick sinus syndrome. Application of multimodal imaging is crucial for accurate diagnosis, appropriate treatment of LASH with ASD, and follow-up. Case summary: A 68-year-old female patient presented with recurrent chest tightness and palpitation. Multimodal imaging revealed the characterizations of LASH and ASD. Two-dimensional transesophageal echocardiography showed a "dumbbell"-shaped involvement of the cephalad and caudal regions with sparing of a single secundum ASD. The septum with a brightness feature is an uncommon condition characterized by the deposition of unencapsulated fat cells in the atrial septum. Real-time four-dimensional transesophageal echocardiography reflected the lipomatous hypertrophy of the atrial septum and an oval-shaped ASD. Cardiac computer tomography angiography later confirmed this finding. The patient achieved a good clinical response with an ASD percutaneous occlusion guided by intracardiac echocardiography (ICE). Conclusion: This case demonstrates a LASH combined with ASD. Multimodality imaging can provide an accurate diagnosis and may guide the procedure for precise occlusion.

Clinical exome sequencing reveals a mutation in PDHA1 in Leigh syndrome: A case of a Chinese boy with lethal neuropathy.

BACKGROUND: Leigh syndrome, the most common mitochondrial syndrome in pediatrics, has diverse clinical manifestations and is genetically heterogeneous. Pathogenic mutations in more than 75 genes of two genomes (mitochondrial and nuclear) have been identified. PDHA1 encoding the E1 alpha subunit is an X-chromosome gene whose mutations cause pyruvate dehydrogenase complex deficiency. METHODS: Here, we have described a 12-year-old boy with lethal neuropathy who almost died of a sudden loss of breathing and successive cardiac arrest. Extracorporeal membrane oxygenation rescued his life. His diagnosis was corrected from Guillain-Barré syndrome to Leigh syndrome 1 month later by clinical exome sequencing. Furthermore, we used software to predict the protein structure caused by frameshift mutations. We treated the boy with vitamin B1, coenzyme Q10, and a ketogenic diet. RESULTS: A PDHA1 mutation (NM_000284.4:c.1167_1170del) was identified as the underlying cause. The amino acid mutation was p.Ser390LysfsTer33. Moreover, the protein structure prediction results suggested that the protein structure has changed. The parents of the child were negative, so the mutation was de novo. The comprehensive assessment of the mutation was pathogenic. His condition gradually improved after receiving treatment. CONCLUSION: This case suggests that gene detection should be popularized to improve diagnosis accuracy, especially in developing countries such as China.

Duplication of 10q22.3-q23.3 encompassing BMPR1A and NGR3 associated with congenital heart disease, microcephaly, and mild intellectual disability.

Chromosome region 10q22.3-q23.3 contains several low copy repeats (LCRs) and is prone to recombination. Deletions with breakpoints within LCR3 and LCR4 have been described to be associated with intellectual disability and dysmorphic features, while the reciprocal duplications are rarely reported. We present an additional case with multiple congenital anomalies that include microcephaly, cardiac defect, and mild intellectual disability, in which a de novo interstitial 8.2-Mb duplication of 10q22.3-q23.3, including BMPR1A and NGR3, was identified by Illumina SNP array platform. Our study is consistent with the hypothesis that the BMPR1A is a plausible candidate gene for congenital heart disease (CHD) and should contribute to the diagnosis and treatment of these genomic diseases.

A novel variant in TBX20 (p.D176N) identified by whole-exome sequencing in combination with a congenital heart disease related gene filter is associated with familial atrial septal defect.

Congenital heart disease (CHD) is the leading cause of birth defects, and its etiology is not completely understood. Atrial septal defect (ASD) is one of the most common defects of CHD. Previous studies have demonstrated that mutations in the transcription factor T-box 20 (TBX20) contribute to congenital ASD. Whole-exome sequencing in combination with a CHD-related gene filter was used to detect a family of three generations with ASD. A novel TBX20 mutation, c.526G>A (p.D176N), was identified and co-segregated in all affected members in this family. This mutation was predicted to be deleterious by bioinformatics programs (SIFT, Polyphen2, and MutationTaster). This mutation was also not presented in the current Single Nucleotide Polymorphism Database (dbSNP) or National Heart, Lung, and Blood Institute (NHLBI) Exome Sequencing Project (ESP). In conclusion, our finding expands the spectrum of TBX20 mutations and provides additional support that TBX20 plays important roles in cardiac development. Our study also provided a new and cost-effective analysis strategy for the genetic study in small CHD pedigree.

Whole-exome sequencing identifies Y1495X of SCN5A to be associated with familial conduction disease and sudden death.

SCN5A mutations have been reported to underlie a variety of inherited arrhythmias, while the complex overlapping phenotype, especially with congenital heart disease (CHD), is rarely reported. The 48-year-old proband underwent a recent syncope during rest. A CHD (tetralogy of Fallot) and conduction disease was revealed by echocardiogram and ultrasonic cardiogram examination. We combined whole-exome sequencing (WES) and bioinformatics strategies to identify the pathogenic gene for this autosomal-dominant cardiac conduction disease (CCD) in a multi-generation pedigree. We examined four members of this family, including three affected and one unaffected. A novel nonsense mutation (Y1495X) in SCN5A was identified in the affected family members. This mutation is predicted to generate a truncated SCN5A protein, which could result in the loss of sodium current, a defined mechanism of SCN5A related arrhythmias. Our study provides evidence that WES is a highly effective approach for genetic analyses of rare clinical phenotypes. Our study also offers accurate genetic testing information for those yet clinically negative relatives.

Rare de novo copy number variants in patients with congenital pulmonary atresia.

BACKGROUND: Ongoing studies using genomic microarrays and next-generation sequencing have demonstrated that the genetic contributions to cardiovascular diseases have been significantly ignored in the past. The aim of this study was to identify rare copy number variants in individuals with congenital pulmonary atresia (PA). METHODS AND RESULTS: Based on the hypothesis that rare structural variants encompassing key genes play an important role in heart development in PA patients, we performed high-resolution genome-wide microarrays for copy number variations (CNVs) in 82 PA patient-parent trios and 189 controls with an Illumina SNP array platform. CNVs were identified in 17/82 patients (20.7%), and eight of these CNVs (9.8%) are considered potentially pathogenic. Five de novo CNVs occurred at two known congenital heart disease (CHD) loci (16p13.1 and 22q11.2). Two de novo CNVs that may affect folate and vitamin B12 metabolism were identified for the first time. A de novo 1-Mb deletion at 17p13.2 may represent a rare genomic disorder that involves mild intellectual disability and associated facial features. CONCLUSIONS: Rare CNVs contribute to the pathogenesis of PA (9.8%), suggesting that the causes of PA are heterogeneous and pleiotropic. Together with previous data from animal models, our results might help identify a link between CHD and folate-mediated one-carbon metabolism (FOCM). With the accumulation of high-resolution SNP array data, these previously undescribed rare CNVs may help reveal critical gene(s) in CHD and may provide novel insights about CHD pathogenesis.

Rare copy number variations containing genes involved in RASopathies: deletion of SHOC2 and duplication of PTPN11.

BACKGROUND: RASopathies are a group of disorders related to Noonan syndrome that with dysregulated RAS-mitogen-activated protein kinase (MAPK) signaling pathway. Noonan syndrome (NS, OMIM# 163950) is a both phenotypically and genotypically variable disorder. We and other researchers have demonstrated that copy number variations underlie a small percentage of patients with RASopathies. RESULTS: In a cohort of 12 clinically characterized patients with congenital heart defect (CHD) and features suggestive of Noonan syndrome or Noonan like syndrome without known causative gene mutation, we performed an Illumina SNP-array analysis to identify the pathogenic copy number variations (Human660W-Quad Chip, Beadstation Scanner and GenomeStudio V2011 software). We identifed two rare copy number variations harboring genes involved in RAS- MAPK signaling pathway of RASopathy. One is a 24 Mb duplication of 12q24.1-24.3 containing PTPN11 and the other is a 183 kb deletion of 10q25.2 including SHOC2. The SNP-array results were further validated by quantitative PCR (qPCR). This is might be the first report suggesting that haploinsufficiency of SHOC2 can result in a RASopathy-like phenotype. CONCLUSIONS: Our findings provide additional support that copy number variations containing disease-causing genes of RAS/MAPK pathway play a minor role in RASopathies or related disorders. We recommend the use of microarrays in Noonan syndrome like patients without identified mutations in the causative genes.

A 1.1Mb deletion in distal 13q deletion syndrome region with congenital heart defect and postaxial polydactyly: additional support for a CHD locus at distal 13q34 region.

13q deletion syndrome is a rare genetic disorder, especially for group 3 deletion (13q33-q34 deletion). Previously we described a patient with congenital heart defect and mental retardation and proposed that a distal 6Mb region might contain the causative gene of congenital heart defect. Here we present a new patient with congenital heart defects (CHD), hand and foot anomalies and mild mental retardation. We identified a 1.1Mb deletion at chromosome 13q34 with high resolution SNP-array BeadChips (HumanOmni1-Quad, Illumina, USA). This chromosome region contains ten annotated genes, including GRK1, TFDP1, RASA3 and GAS6. To our knowledge, this represents the smallest 13q34 deletion identified to date. Our study provides additional support that distal 13q34 deletion region might contain key gene(s) responsible for cardiac development.

[Effects of early environment on the expression of brain-derived neurotrophic factor and its receptor and brain development].

OBJECTIVE: To study the effect of early environment on the learning-memory ability of rats and the expression of brain-derived neurotrophic factor (BDNF) and its receptor, tyrosine kinase receptor B (TrkB), and to explore the influence of early environment on development of rat brain in developing stage and possible regulation mechanisms. METHODS: Forty-five newborn Sprague-Dawley rats were randomly divided into three groups (15 rats in each group): enriched environment group (EE group), isolated environment group (IE group) and normal control group (NC group). The pups were nurtured separately in their groups. The learning-memory abilities of the rats were measured by "Y"-arm maze test 28 to 29 days after birth. The number of neural cells and the expression of BDNF and TrkB in the hippocampal CA3 and frontal lobe were were detected by Nissl's staining and immunohistochemistry respectively. RESULTS: The results of the "Y"-arm maze test showed that rats in the EE group needed less training times, and retained a higher percentage of memory than the other two groups(P<0.01). Rats in the IE group needed more training times, and retained a lower percentage of memory than the NC group (P<0.01). By Nissl's staining, the numbers of neural cells in the hippocampal CA3 and frontal lobe were highest in the EE group followed by the NC group. They were lowest in the IE group (P<0.01). By immunohistochemistry, the expression of BDNF in the hippocampal CA3 and frontal lobe were highest in the EE group followed by the NC group. It was lowest in the IE group (P<0.01). Results were similar for expression of TrkB. CONCLUSIONS: Early environment can affect the long-term brain development and brain function of rats by influencing the expression of BDNF and its receptor TrkB in the hippocampus and frontal lobe.

Duplication of 8q12 encompassing CHD7 is associated with a distinct phenotype but without duane anomaly.

Interstitial duplications of 8q12 encompassing CHD7 have recently been described as a new microduplication syndrome. Three 8q12 duplications have been reported with shared recognizable phenotype: Duane anomaly, developmental delay and dysmorphic facial features. We identified a 2.7 Mb duplication on chromosome 8q12 with SNP-array in a patient with growth delay, congenital heart defects, ear anomalies and torticollis. To our knowledge, this is the smallest duplication reported to date. Our findings support the notion that increased copy number of CHD7 may underlie the phenotype of the 8q12 duplication. Our study together with previous studies suggest that the 8q12 duplication could be defined as a novel syndrome.

Microduplication of 3p25.2 encompassing RAF1 associated with congenital heart disease suggestive of Noonan syndrome.

Noonan syndrome (NS) is a clinically variable and genetically heterogeneous disorder with congenital heart defects (CHD), short stature, and craniofacial dysmorphisms. Gain-of-function mutations in RAF1 can cause NS and the highly related NS with multiple lentigines (previously known as LEOPARD syndrome). Here we report on a 15-year-old male with NS phenotype: short stature, heart defects, low posterior hairline, facial malformations, malformed left ear with sensorineural hearing loss, widely spaced nipples, and unilateral upper limb anomaly. Using high-resolution SNP array technology, we identified in this patient a 0.25 Mb microduplication at 3p25.2 in which RAF1 is located. Sequence analysis did not identify mutations in genes associated with Holt-Oram syndrome. These findings suggest that duplications of genomic regions encompassing RAF1 could cause NS and are consistent with the notion that rare copy number variations encompassing causative genes may underlie a small percentage of patients with syndromic CHD like NS.

Congenital heart defect and mental retardation in a patient with a 13q33.1-34 deletion.

13q deletion syndrome is a rare genetic disorder caused by deletions of the long arm of chromosome 13. Patients with 13q deletion display a variety of phenotypic features. We describe a one-year-old female patient with congenital heart defects (CHD), facial anomalies, development and mental retardation. We identified a 12.75Mb deletion in chromosome region 13q33.1-34 with high resolution SNP Array (Human660W-Quad, Illumina, USA). This chromosome region contains about 55 genes, including EFNB2, ERCC5, VGCNL1, F7, and F10. Comparing our findings with previously reported 13q deletion patients with congenital heart defects, we propose that the 13q33.1-34 deletion region might contain key gene(s) associated with cardiac development. Our study also identified a subclinical deficiency of Factors VII and X in our patient with Group 3 of 13q deletion syndrome.

One-stage correction of aortic coarctation and severe mitral regurgitation via left posteriolateral thoracotomy in a 2-year-old child.

We successfully treated a case of a 2-year-old male with aortic coarctation coexisting with severe mitral regurgitation via left posteriolateral thoracotomy at one stage. After a mitral valve replacement under perfused ventricular fibrillation with moderate hypothermia, we repaired the aortic coarctation with coarctation resection and end-to-end anastamosis with the aid of deep hypothermic circulatory arrest and selective low-flow cerebral perfusion. The patient had an uneventful hospital course and remains well.

[Multifactor analysis of postoperative mechanical ventilation supporting time in infants with congenital heart diseases].

OBJECTIVE: To analyze the multiple factors affecting the postoperative mechanical ventilation supporting time in infants less than 10 kg with simple congenital heart diseases and to seize time by the forelock of extube and improve the outcome of surgical treatment. METHODS: Data of 231 infants less than 10 kg with atrial septal defect(ASD),ventricular septal defect, and combining patent ductus arteriosus were retrospectively analyzed. The multivaricate stepwise logistic regression statistics were done for the predisposing factors affecting the ventilative supporting time. RESULTS: The ventilative supporting time was 3~375 (average 23.5 h) h. The multivaricate stepwise logistic regression analysis indicated that severe pulmonary hyperpressure, cross-cramp aortic time, cardiopulmonary bypass time, preoperational pulmonary infection, membrane oxygenator, modified ultrafiltration, weight, and postoperative complications were significantly correlated to the ventilative supporting time. CONCLUSION: Severe pulmonary hyperpressure, preoperational pulmonary infection, long cross-cramp aortic time, long cardiopulmonary bypass time, postoperative complications all prolong the ventilation supporting time; the use of membrane oxygenator and modified ultrafiltration during the operation and big weight can diminish the pulmonary complications and shorten the ventilation supporting time.