Familial recurrence of congenital heart disease in patients with ostium secundum atrial septal defect

Recurrence pattern of non-syndromic familial congenital heart diseases among a large cohort of families from Egypt

Background

Congenital heart diseases (CHD) are the commonest congenital anomalies with increased risk in children born from families with affected members. However, various recurrence patterns of CHDs have been reported in different populations. Therefore, this work aimed to assess the recurrence patterns of CHDs in a large sample of Egyptian families.

Methods

From January 2020 to October 2021, non-syndromic children with confirmed CHDs were recruited. Data were collected from guardians of the recruited children and hospital records, including the index case’s cardiac diagnosis and CHD diagnosis of other affected family members with to determine their recurrence pattern, consanguinity, and multi-gestation status.

Results

A total of 130 recurrent cases with CHD were documented in 1960 families of children with CHD, including 66,989 members. Most recurrences were detected among first-degree relatives 50/130 (38.46%), especially siblings. Discordant recurrence was the most detected pattern (45.38%), followed by concordant recurrence (42.31%), and the least was group concordance. Recurrence rate was the highest for septal defects with left ventricular outflow tract obstruction (LVOTO) (11.8%) and anomalous venous drainage (11.1%), followed by septal defect with right ventricular outflow tract obstruction (RVOTO) (9.4%), isolated ventricular septal defect (VSD) category (8.2%) and LVOTO (8%). Familial recurrence was significant in consanguineous marriages [p = 0.0001; OR (95%CI) = 4.5 (2.25–9.01)] and in multi-gestations siblings: [p = 0.036; OR (95%CI) = 12.5(1.03–6.04)].

Conclusion

The recurrence of non-syndromic CHD is evident among first-degree relatives in Egyptian families, with mostly a discordant recurrence pattern. Recurrence was more notable in septal defects with LVOTO, anomalous venous drainage, septal defect with RVOTO, isolated VSD, and isolated LVOTO diagnostic categories. This finding will significantly impact family counseling, emphasizing higher recurrence in consanguineous parents.

Supplementary information

The online version contains supplementary material available at 10.1186/s12887-022-03640-4.

GATA4 variant identified by whole-exome sequencing in a Japanese family with atrial septal defect: Implications for male sex development

We identified a heterozygous p.(R284H) variant of GATA4 in a Japanese family with atrial septal defect, including boys with apparently normal male sex development. The findings, together with the previous data, imply that GATA4 variants primarily cause congenital heart disease and rarely result in 46,XY disorder of sex development.

Identification of LBX2 as a novel causal gene of atrial septal defect

BACKGROUND

Atrial septal defect (ASD) is one of the most common cardiac malformations worldwide. Several genes have been identified so far, which can merely explain small proportion of all the cases, therefore, it is anticipated that there are additional genes causing ASD. The aims of this study were to identify the causal gene of ostium secundum atrial septal defect (ASDII) in a Chinese family.

METHODS

Whole exome sequencing was performed in three affected members and one control in the ASDII family. We screened mutations of LBX2 in 300 unrelated ASD patients and validated in 400 normal controls by Sanger sequencing. LBX2 knockout zebrafish was generated by CRISPR/Cas9 to detect whether lbx2 deficiency influenced cardiac development.

RESULTS

A rare missense mutation in LBX2 (c.A403G: p.K135E) was identified as the pathogenic cause of ASD. Subsequent mutation screening revealed two missense variants in 3 of 300 sporadic patients. We observed expanded size of atrium and ventricle in LBX2 knockout zebrafish through hematoxylin-eosin staining, more incompact distribution of cardiac myocytes was also discovered in homozygote compared with in wildtype. Furthermore, we performed in situ hybridization of crip2 gene to trace the cardiac neural crest cells in the embryo stage and found that the migration of neural crest cells was obviously delayed in the homozygotes.

CONCLUSIONS

We identified LBX2 for the first time as a pathogenic gene of ASDII. LBX2 deficiency may cause abnormal development of heart through influencing the migration of neural crest cells and affect the process of cardiac septation.

Familial Atrial Septal Defect and Sudden Cardiac Death: Identification of a Novel NKX2-5 Mutation and a Review of the Literature

OBJECTIVE

Atrial septal defect (ASD) is the second most common congenital heart defect (CHD) and is observed in families as an autosomal dominant trait as well as in nonfamilial CHD. Mutations in the NKX2-5 gene, located on chromosome 5, are associated with ASD, often combined with conduction disturbances, cardiomyopathies, complex CHD, and sudden cardiac death as well. Here, we show that NKX2-5 mutations primarily occur in ASD patients with conduction disturbances and heritable ASD. Furthermore, these families are at increased risk of sudden cardiac death.

RESULTS

We screened 39 probands with familial CHD for mutations in NKX2-5 and discovered a novel mutation in one family (2.5%) with ASD and atrioventricular block. A review of the literature revealed 59 different NKX2-5 mutations in 202 patients. Mutations were significantly more common in familial cases compared to nonfamilial cases (P = 7.1 × 10(-9) ). The majority of patients (74%) had ASD with conduction disturbance. Nineteen patients (15%) of 120 with familial ASD and conduction disturbance died from sudden cardiac death of which nine (8%) were confirmed mutation carriers, and 10 were possible carriers.

CONCLUSIONS

NKX2-5 mutations mainly occur in familial CHD, the signature phenotype is ASD with conduction disturbances and mutation carriers are at increased risk of sudden cardiac death. We suggest that familial ASD patients should be screened for NKX2-5 mutations and, if they are mutation carriers, implantation of an implantable cardioverter-defibrillator should be considered in these patients.

Atrial septal defects

Atrial septal defects are the third most common type of congenital heart disease. Included in this group of malformations are several types of atrial communications that allow shunting of blood between the systemic and the pulmonary circulations. Most children with isolated atrial septal defects are free of symptoms, but the rates of exercise intolerance, atrial tachyarrhythmias, right ventricular dysfunction, and pulmonary hypertension increase with advancing age and life expectancy is reduced in adults with untreated defects. The risk of development of pulmonary vascular disease, a potentially lethal complication, is higher in female patients and in older adults with untreated defects. Surgical closure is safe and effective and when done before age 25 years is associated with normal life expectancy. Transcatheter closure offers a less invasive alternative for patients with a secundum defect who fulfil anatomical and size criteria. In this Seminar we review the causes, anatomy, pathophysiology, treatment, and outcomes of atrial septal defects in children and adult patients in whom this defect is the primary cardiac anomaly.

Percutaneous Interventional Treatment of Atrial Septal Defect Secundum in Macedonia

Background: Atrial septal defect (ASD) is a common congenital heart disorder (CHD). While conventional open surgical treatment is the standard procedure in our country, percutaneous device closure with implantation of an atrial septal defect occluder is a promising alternative with very few peri and post procedural complications.Aim: The aim of the study was to present the rate of success and complications in percutaneous ASD closure with the implantation of an atrial septal defect occluder.Material and Methods: We treated 153 patients (ages 2-76; 65% female) with ASD secundum with percutaneous trans catheter closure using a septal occluder. Follow up was on a 3 month interval and assessment included clinical, electrophysiological and echocardiographic status. Results: The mean diameter of ASD obtained via balloon sizing was 16 ± 16 mm. Multiple ASDs were found in 20 (13%) patients and deficitary aortic and anterior rim (< 5 mm) was present in 16 (10%) patients. Due to inadequate placement and/or sizing, the device was removed and replaced in seven patients (5%). During follow up, trivial shunt was present in 4 (2.6%) patients. The diameter of the right ventricle corrected for age was reduced by an average of 20% by the first month and in 130 (86%) of patients it had normalized by one year of follow up. During follow up, 16 (10%) patients reported transient headaches and 3 (1.9%) patients had transient atrial fibrillation (AF).Conclusion: In conclusion, the implantation of a septal occluder was found to be a safe procedure that resulted in improved hemodynamic parameters that result from right ventricular volume overload with favorable short- and mid-term results.

Molecular genetics of congenital atrial septal defects

Congenital heart defects (CHD) are the most common developmental errors in humans, affecting 8 out of 1,000 newborns. Clinical diagnosis and treatment of CHD has dramatically improved in the last decades. Hence, the majority of CHD patients are now reaching reproductive age. While the risk of familial recurrence has been evaluated in various population studies, little is known about the genetic pathogenesis of CHD. In recent years significant progress has been made in uncovering genetic processes during cardiac development. Data from human genetic studies in CHD patients indicate that the genetic aetiology was presumably underestimated in the past. Inherited mutations in genes encoding cardiac transcription factors and sarcomeric proteins were found as an underlying cause for familial recurrence of non-syndromic CHD in humans, in particular cardiac septal defects. Notably, the cardiac phenotypes most frequently seen in mutation carriers are ostium secundum atrial septal defects (ASDII). This review outlines experimental approaches employed for the detection of CHD-related genes in humans and summarizes recent findings in molecular genetics of congenital cardiac septal defects with an emphasis on ASDII.

Population-based assessment of familial inheritance and neurologic comorbidities among patients with an isolated atrial septal defect

BACKGROUND

Interatrial shunts, caused by either atrial septal defect (ASD) or patent foramen ovale, have been reported to have a familial association. We sought to examine the familial risk of isolated interatrial shunt and explore associated comorbidities of stroke, transient ischemic attack (TIA), and migraine using a population database.

METHODS

The Utah Population Database is linked to inpatient and outpatient records from the University of Utah Health Science Center. Patients with an interatrial shunt were identified, and those with any other form of congenital heart disease or an inheritable syndrome associated with ASD were excluded. Of the 9452 individuals diagnosed with isolated interatrial shunt, 6179 (65%) had sufficient familial and follow-up data for analysis. Five age/gender matched controls were randomly selected per case. Cases and their relatives were compared with controls to assess the relative risk for each comorbid condition.

RESULTS

Relatives of interatrial shunt cases had an increased risk for interatrial shunt: siblings relative risk (RR) 6.98 (95% confidence interval [CI] 5.75-8.48; P < 1.0 x 10(-16)), first-degree RR 5.64 (95% CI 4.76-6.68; P < 1.0 x 10(-16)), and second-degree RR 1.75 (95% CI 1.32-2.32; P= 0.0001). Patients with interatrial shunt were more likely to have a comorbid condition compared with controls (RR 21.3, 95% CI 17.1-26.5; P < 1.0 x 10(-16)). First-degree relatives of cases had an increased risk of TIA (RR 1.70, 95% CI 1.18-2.45; P= 0.0045), but no increase risk of stroke or migraine compared with controls.

CONCLUSIONS

There is a strong familial inheritance pattern for isolated interatrial shunt, with significantly higher risk of interatrial shunt among affected patients' siblings, first-, and second-degree relatives. Relatives of affected individuals also had a higher risk of TIA, a trend toward an increased risk for stroke, but no increased risk of migraine headache.

A gain-of-function TBX20 mutation causes congenital atrial septal defects, patent foramen ovale and cardiac valve defects

BACKGROUND

Ostium secundum atrial septal defects (ASDII) account for approximately 10% of all congenital heart defects (CHD), and mutations in cardiac transcription factors, including TBX20, were identified as an underlying cause for ASDII. However, very little is known about disease penetrance in families and functional consequences of inherited TBX20 mutations.

METHODS

The coding region of TBX20 was directly sequenced in 170 ASDII patients. Functional consequences of one novel mutation were investigated by surface plasmon resonance, CD spectropolarymetry, fluorescence spectrophotometry, luciferase assay and chromatin immunoprecipitation.

RESULTS

We found a novel mutation in a highly conserved residue in the T-box DNA binding domain (I121M) segregating with CHD in a three generation kindred. Four mutation carriers revealed cardiac phenotypes in terms of cribriform ASDII, large patent foramen ovale or cardiac valve defects. Interestingly, tertiary hydrophobic interactions within the mutant TBX20 T-box were significantly altered leading to a more dynamic structure of the protein. Moreover, Tbx20-I121M resulted in a significantly enhanced transcriptional activity, which was further increased in the presence of co-transcription factors GATA4/5 and NKX2-5. Occupancy of DNA binding sites on target genes was also increased.

CONCLUSIONS

We suggest that TBX20-I121M adopts a more fluid tertiary structure leading to enhanced interactions with cofactors and more stable transcriptional complexes on target DNA sequences. Our data, combined with that of others, suggest that human ASDII may be related to loss-of-function as well as gain-of-function TBX20 mutations.

Pregnancy and adult congenital heart disease

Increasing numbers of women with complex congenital heart disease are reaching childbearing age. Pregnancy is a major issue in the management of adult congenital heart disease. Cardiac disease is one of the most common causes of maternal morbidity and mortality. Complications, such as growth retardation, preterm and premature birth and even fetal and neonatal mortality, are more frequent among children of women with congenital heart disease. The risk of complications is determined by the severity of the cardiac lesion, the presence of cyanosis, the maternal functional class and the use of anticoagulation. However, the pathophysiology of these complications is not completely understood and may be related to a diminished increase in cardiac output and/or endothelial dysfunction. The management of pregnant cardiac patients is based on limited clinical information. This article reviews pre-pregnancy counseling and management during pregnancy in patients with congenital heart disease.