Acyanotic and Cyanotic Congenital Heart Diseases

Paediatrics congenital heart disease is associated with plasma miRNAs

BACKGROUND

Congenital heart disease (CHD) are the most common malformations from birth. The severity of the different forms of CHD varies extensively from superficial mild lesions with follow-up for decades without any treatment to complex cyanotic malformations requiring urgent surgical intervention. microRNAs have been found to be crucial in cardiac development, giving rise to possible phenotypes in CHD.

OBJECTIVES

We aimed to evaluate the expression of miRNAs in 86 children with CHD and divided into cyanotic and non-cyanotic heart defects and 110 controls.

METHODS

The miRNAs expression of miR-21-5p, miR-155-5p, miR-221-3p, miR-26a-5p, and miR-144-3p were analyzed by RT-qPCR. In addition, the expressions of the miRNAs studied were correlated with the clinical characteristics of both the children and the mothers.

RESULTS

The expression levels of miR-21-5-5p, miR-15-5p5, miR-221-3p, and miR-26-5p significantly differed between CHD and control subjects. Moreover, miR-21-5p levels were higher in patients with cyanotic versus non-cyanotic CHD patients.

CONCLUSION

The expression levels of miRNAs of pediatric patients with CHD could participating in the development of cardiac malformations. Additionally, the high expression of miR-21-5p in cyanotic CHD children may be related to greater severity of illness relative to non-cyanotic CHD.

IMPACT

This study adds to knowledge of the association between microRNAs and congenital heart disease in children. The expression levels of miR-21-5-5p, miR-15-5p5, miR-221-3p, and miR-26-5p of pediatric patients with CHD could be involved in the development and phenotype present in pediatric patients. miR-21-5p may help to discriminate between cyanotic and non-cyanotic CHD. In the future, the miRNAs studied could have applications as clinical biomarkers.

Role of miRNA in Cardiovascular Diseases in Children-Systematic Review

The number of children suffering from cardiovascular diseases (CVDs) is rising globally. Therefore, there is an urgent need to acquire a better understanding of the genetic factors and molecular mechanisms related to the pathogenesis of CVDs in order to develop new prevention and treatment strategies for the future. MicroRNAs (miRNAs) constitute a class of small non-coding RNA fragments that range from 17 to 25 nucleotides in length and play an essential role in regulating gene expression, controlling an abundance of biological aspects of cell life, such as proliferation, differentiation, and apoptosis, thus affecting immune response, stem cell growth, ageing and haematopoiesis. In recent years, the concept of miRNAs as diagnostic markers allowing discrimination between healthy individuals and those affected by CVDs entered the purview of academic debate. In this review, we aimed to systematise available information regarding miRNAs associated with arrhythmias, cardiomyopathies, myocarditis and congenital heart diseases in children. We focused on the targeted genes and metabolic pathways influenced by those particular miRNAs, and finally, tried to determine the future of miRNAs as novel biomarkers of CVD.

Risk factors of gastrointestinal bleeding after cardiopulmonary bypass in children: a retrospective study

Background

During cardiac surgery that involved cardiopulmonary bypass (CPB) procedure, gastrointestinal (GI) system was known to be vulnerable to complications such as GI bleeding. Our study aimed to determine the incidence and risk factors associated with GI bleeding in children who received CPB as part of cardiac surgery.

Methods

This retrospective study enrolled patients aged <18 years who underwent cardiac surgery with CPB from 2013 to 2019 at Shanghai Children's Medical Center. The primary outcome was the incidence of postoperative GI bleeding in children, and the associated risk factors with postoperative GI bleeding episodes were evaluated.

Results

A total of 21,893 children who underwent cardiac surgery with CPB from 2013 to 2019 were included in this study. For age distribution, 636 (2.9%) were neonates, 10,984 (50.2%) were infants, and 10,273 (46.9%) were children. Among the 410 (1.9%) patients with GI bleeding, 345 (84.2%) survived to hospital discharge. Incidence of GI bleeding in neonates, infants and children were 22.6% (144/636), 2.0% (217/10,984) and 0.5% (49/10,273), respectively. The neonates (22.6%) group was associated with highest risk of GI bleeding. Patients with GI bleeding showed longer length of hospital stays (25.8 ± 15.9 vs. 12.5 ± 8.9, P < 0.001) and higher mortality (15.9% vs. 1.8%, P < 0.001). Multivariate logistic regression analysis showed that age, weight, complicated surgery, operation time, use of extracorporeal membrane oxygenation (ECMO), low cardiac output syndrome (LCOS), hepatic injury, artery lactate level, and postoperative platelet counts were significantly associated with increased risk of GI bleeding in children with congenital heart disease (CHD) pediatric patients that underwent CPB procedure during cardiac surgery.

Conclusion

The study results suggest that young age, low weight, long operation time, complicated surgery, use of ECMO, LCOS, hepatic injury, high arterial lactate level, and low postoperative platelet counts are independently associated with GI bleeding after CPB in children.

An examination of the psychosocial consequences experienced by children and adolescents living with congenital heart disease and their primary caregivers: a scoping review protocol

BACKGROUND

The chronicity of congenital heart disease (CHD) comes with significant psychosocial consequences for both children and adolescents living with CHD and their primary caregivers. Children and adolescents living with CHD undergo multiple traumatizing invasive surgical and medical procedures, struggle with disabilities resulting from their CHD, face unfair scrutiny and marginalization, and are at risk for mental health issues. Primary caregivers of children and adolescents living with CHD deal with increased stress, fear, anxiety, depression, and financial burden. The overarching objectives of this scoping review are to (1) determine the current state of knowledge on negative psychosocial consequences experienced by children and adolescents living with CHD and their primary caregivers in high-income countries and (2) inform research aimed at developing interventions in high-income countries to decrease the negative psychosocial consequences experienced by children and adolescents living with CHD and their primary caregivers.

METHODS

Databases and grey literature searched will include MEDLINE, CINAHL, EMBASE, PsycINFO, CENTRAL, Scopus, ProQuest Theses and Dissertations, and Google advanced search. Citation mining of included studies and relevant review articles will be completed. Studies will be screened by title and abstract and then full text by two independent reviewers, using pre-defined inclusion and exclusion criteria. Quality analysis will be conducted on all included studies by two reviewers using MMAT Version 2018. Studies will not be excluded due to quality assessment. Data from all eligible studies will be independently extracted by the two reviewers and verified by consensus. Data will be presented and synthesized in evidence tables to examine potential patterns.

DISCUSSION

The results of this review will provide recognition of the psychosocial impact of CHD and its treatments on children and adolescents living with CHD and their primary caregivers. It will also highlight interventions that have been developed to decrease these psychosocial consequences. The results from this review will inform a future integrated knowledge translation study by the first author aimed at decreasing one or more of the negative psychosocial consequences experienced by children or adolescents living with CHD and their primary caregivers.

SYSTEMATIC REVIEW REGISTRATION

Open Science Framework (OSF) Registration, https://doi.org/10.17605/OSF.IO/ZXYGW.

A Single Center Observational Study of Spirometry Assessments in Children with Congenital Heart Disease after Surgery

Background: Children with congenital heart disease (CHD) have impaired pulmonary function both before and after surgery; therefore, pulmonary function assessments are important and should be performed both before and after open-heart surgery. This study aimed to compare pulmonary function between variant pediatric CHD types after open-heart surgery via spirometry. Methods: In this retrospective study, the data for forced vital capacity (FVC), forced expiratory volume in the first second (FEV1), and the ratio between FEV1 and FVC (FEV1/FVC) were collected from patients with CHD who underwent conventional spirometry between 2015 and 2017. Results: A total of 86 patients (55 males and 31 females, with a mean age of 13.24 ± 3.32 years) were enrolled in our study. The diagnosis of CHD included 27.9% with atrial septal defects, 19.8% with ventricular septal defects, 26.7% with tetralogy of Fallot, 7.0% with transposition of the great arteries, and 46.5% with other diagnoses. Abnormal lung function was identified by spirometry assessments after surgery. Spirometry was abnormal in 54.70% of patients: obstructive type in 29.06% of patients, restrictive type in 19.76% of patients, and mixed type in 5.81% of patients. More abnormal findings were found in patients who received the Fontan procedure (80.00% vs. 35.80%, p = 0.048). Conclusions: Developing novel therapies to optimize pulmonary function will be critical for improving clinical outcomes.

Exposure to essential and non-essential trace elements and risks of congenital heart defects: A narrative review

Congenital heart defects (CHDs) are congenital abnormalities involving the gross structures of the heart and large blood vessels. Environmental factors, genetic factors and their interactions may contribute to the pathogenesis of CHDs. Generally, trace elements can be classified into essential trace elements and non-essential trace elements. Essential trace elements such as copper (Cu), zinc (Zn), iron (Fe), selenium (Se), and manganese (Mn) play important roles in human biological functions such as metabolic function, oxidative stress regulation, and embryonic development. Non-essential trace elements such as cadmium (Cd), arsenic (As), lead (Pb), nickle (Ni), barium (Ba), chromium (Cr) and mercury (Hg) are harmful to health even at low concentrations. Recent studies have revealed the potential involvement of these trace elements in the pathogenesis of CHDs. In this review, we summarized current studies exploring exposure to essential and non-essential trace elements and risks of CHDs, in order to provide further insights for the pathogenesis and prevention of CHDs.

Spectrum of congenital heart disease in Nepal from 2002-2022: A systematic review and meta-analysis

Background

Congenital heart diseases are recognized as public health concerns worldwide and Nepal is no exception. This study aims to study congenital heart disease in Nepal on grounds of burden, commonest type, common presentations, and associated noncardiac anomalies so that its spectrum can be known for prompt diagnosis and adoption of screening protocols.

Methods

Relevant articles were searched in electronic databases using appropriate search terms and Boolean operators. Data were extracted in Excel and analyzed in Comprehensive Meta-Analysis Software. The proportion was used as an effect measure and a fixed or random-effect model was used as per the heterogeneity. Forest plots were used to give visual feedback.

Results

A total of nine studies were included in the qualitative and quantitative synthesis after a rigorous screening of imported studies. The prevalence of congenital heart disease was 0.7% (Proportion: 0.007; CI: 0.001-0.035; I²: 99.263%). The burden of atrial septal defect was 32.1%, ventricular septal defect was 31.1%, patent ductus arteriosus was 12.6% and Tetralogy of Fallot was 7.3%. The most common presentations were respiratory tract infection (54.7%), developmental delay (49.8%), difficulty in breathing (44.5%), failure to thrive (17.1%), and cyanosis (15.9%).

Conclusions

The prevalence of congenital heart disease in Nepal was 0.7% and the frequency of male patients was higher. The atrial septal defect was the commonest on the whole, while, Tetralogy of Fallot was the commonest among cyanotic variety. Respiratory tract infection was frequently seen at presentation and the most commonly associated noncardiac anomaly was the cleft palate.

Biological Scaffolds for Congenital Heart Disease

Congenital heart disease (CHD) is the most predominant birth defect and can require several invasive surgeries throughout childhood. The absence of materials with growth and remodelling potential is a limitation of currently used prosthetics in cardiovascular surgery, as well as their susceptibility to calcification. The field of tissue engineering has emerged as a regenerative medicine approach aiming to develop durable scaffolds possessing the ability to grow and remodel upon implantation into the defective hearts of babies and children with CHD. Though tissue engineering has produced several synthetic scaffolds, most of them failed to be successfully translated in this life-endangering clinical scenario, and currently, biological scaffolds are the most extensively used. This review aims to thoroughly summarise the existing biological scaffolds for the treatment of paediatric CHD, categorised as homografts and xenografts, and present the preclinical and clinical studies. Fixation as well as techniques of decellularisation will be reported, highlighting the importance of these approaches for the successful implantation of biological scaffolds that avoid prosthetic rejection. Additionally, cardiac scaffolds for paediatric CHD can be implanted as acellular prostheses, or recellularised before implantation, and cellularisation techniques will be extensively discussed.

The Experience of Uncertainty in Mothers Caring for Children at Home after Palliative Heart Surgery

Objectives

Palliative heart surgery is a compelling option for some children with congenital heart disease for which corrective heart surgery is not yet possible due to its complexity. As primary caregivers, mothers have the challenge of providing optimal care to their children at home post-surgery. This study aims to explore the experiences of mothers who are caring for children recovering from palliative heart surgery at home. The research applied descriptive, qualitative and phenomenology design.

Material and Methods

This study was conducted in Jakarta. The participants were 15 mothers of palliative heart surgery patients from seven provinces in Indonesia; Jakarta, Aceh, Bali, North Sumatra, West Java, Central Java and Banten. Data were collected using semi-structured interviews through the WhatsApp video call application and analysed using the Colaizzi method.

Results

Mothers often felt uncertain about how to provide the best care and felt that their needs for hospital services to assist them went unmet. Conclusions: This study has implications for the development of nursing services related to discharge planning for palliative heart surgery patients.

Early Cerebrovascular Autoregulation in Neonates with Congenital Heart Disease

Neonates with congenital heart disease (CHD) display delayed brain development, predisposing them to impaired cerebrovascular autoregulation (CAR) and ischemic brain injury. For this paper, we analyzed the percentage of time with impaired CAR (%time impaired CAR) during the first 72 h after birth, the relation with clinical factors, and survival in 57 neonates with CHD. The primary outcome was a correlation coefficient of cerebral oxygenation (rcSO2) and mean arterial blood pressure (MABP, mmHg) for two hours on a daily basis. The %time impaired CAR ranged from 9.3% of the studied time on day one to 4.6% on day three. Variables associated with more %time impaired CAR were the use of inotropes (day 1, B = 19.5, 95%CI = 10.6–28.3; day 3, B = 11.5, 95%CI = 7.1–16), lower MABP (day 1, B = −0.6, 95%CI = −1.2–0.0), and dextro-transposition of the great arteries (dTGA) (16.2%) compared with other CHD types (2.0–5.0%; day 1, p = 0.022). Survival was not an associated variable. To summarize, impaired CAR was found in CHD neonates in up to 9.3% of the studied time. More evidence is necessary to evaluate an association with inotropes, dTGA, %time impaired CAR, and long-term outcome, further in larger cohorts.

Accelerated Cardiac Aging in Patients With Congenital Heart Disease

An increasing number of patients with congenital heart disease (CHD) survive into adulthood but develop long-term complications including heart failure (HF). Cellular senescence, classically defined as stable cell cycle arrest, is implicated in biological processes such as embryogenesis, wound healing, and aging. Senescent cells have a complex senescence-associated secretory phenotype (SASP), involving a range of pro-inflammatory factors with important paracrine and autocrine effects on cell and tissue biology. While senescence has been mainly considered as a cause of diseases in the adulthood, it may be also implicated in some of the poor outcomes seen in patients with complex CHD. We propose that patients with CHD suffer from multiple repeated stress from an early stage of the life, which wear out homeostatic mechanisms and cause premature cardiac aging, with this term referring to the time-related irreversible deterioration of the organ physiological functions and integrity. In this review article, we gathered evidence from the literature indicating that growing up with CHD leads to abnormal inflammatory response, loss of proteostasis, and precocious age in cardiac cells. Novel research on this topic may inspire new therapies preventing HF in adult CHD patients.

Oxidative stress response in children undergoing cardiac surgery: Utility of the clearance of isoprostanes

INTRODUCTION

Cardiac surgery (CS) in pediatric patients induces an overt oxidative stress (OS) response. Children are particularly vulnerable to OS related injury. The immaturity of their organs and antioxidant systems as well as the induction of OS in cardio-pulmonary bypass (CPB) surgery may have an important impact on outcomes. The purpose of this study was to describe the OS response, measured by urinary free 8-iso-PGF2α, in infants undergoing CS and to evaluate the relationship between OS response and post-operative clinical outcomes.

METHODS

Infants with congenital heart disease undergoing CS with or without CPB were eligible for enrollment. Children were classified as neonates (<30 days) or infants (30 days-6 months) based on the age at surgery. Perioperative continuous non-invasive neuromonitoring included amplitude-integrated electroencephalogram and cerebral regional oxygen saturation measured with near-infrared spectroscopy. Urine 8-iso-PGF2α levels were measured before, immediately post-, and 24-hours post-surgery, and the 8-iso-PGF2 clearance was calculated.

RESULTS

Sixty-two patients (60% neonates) were included. Urine 8-iso-PGF2α levels 24 hours after surgery (8.04 [6.4-10.3] ng/mg Cr) were higher than pre-operative levels (5.7 [4.65-7.58] ng/mg Cr) (p<0.001). Those patients with a severe degree of cyanosis caused by Transposition of the Great Arteries (TGA) had the highest post-operative 8-iso-PGF2α levels. Patients with intra-operative seizures had higher post-operative 8-iso-PGF2α levels. 8-iso-PGF2α clearance at 24 hours post-surgery was different between newborns and infant patients, and it was inversely correlated with days of mechanical ventilation (p = 0.05), ICU LOS (p = 0.05) and VIS score at 24 hours (p = 0.036).

CONCLUSIONS

Children undergoing CS, particularly neonatal patients, experience a significant post-operative OS response that might play an important role in postoperative morbidity. TGA patients undergoing arterial switch operations demonstrate the highest post-operative OS response. Rapid clearance of isoprostanes, which occurs more frequently in older patients with more mature antioxidant systems, might be associated with better clinical outcomes.

Age Differences in the Mediating Effects of Parenting Stress on the Relationship Between Cyanotic Congenital Heart Disease and Externalizing Problems in Children and Adolescents

BACKGROUND

Cyanotic congenital heart disease (CHD) has detrimental effects on behavioral function in children and adolescents. However, few study authors have examined the underlying mechanisms of these effects.

OBJECTIVE

The aims of this study were to investigate the mediating effects of parenting stress in the association between cyanotic CHD and externalizing problems and to explore whether age moderated these mediating effects.

METHODS

A total of 697 children and adolescents (aged 2-17 years) with CHD (252 with cyanotic CHD and 445 with acyanotic CHD) in Taiwan were enrolled. The Child Behavior Checklist and the Parenting Stress Index were used to assess externalizing problems and parenting stress, respectively. Mediation analysis was performed to determine the mediating effects of parenting stress in the association between cyanotic CHD and externalizing problems. A moderated mediation model was used to investigate the moderating effect of age on the observed mediating effects.

RESULTS

Parenting stress significantly mediated the relationship between cyanotic CHD and externalizing problems (unstandardized coefficient B = 0.98; 95% bootstrap confidence interval, 0.23-1.78). Children's age further moderated the mediating effects, with greater effects in older children. Age also moderated the association between cyanotic CHD and parenting stress, such that the effects were only significant in children older than 5.7 years.

CONCLUSIONS

Our study revealed that age affected the mediating effects of parenting stress in the relationship between cyanotic CHD and externalizing problems. Efforts to reduce externalizing problems in children and adolescents with cyanotic CHD by targeting parenting stress may be more effective when age differences are considered.

ED50 of Intranasal Dexmedetomidine Sedation for Transthoracic Echocardiography in Children with or without a History of Cardiac Surgery for Cyanotic Congenital Heart Disease

Methods

This prospective single-blinded clinical trial included 72 ASA I-II stage children aged 1-36 months with cCHD who were scheduled to undergo TTE under sedation. Children were assigned to group A (n = 37) with a previous history of cardiac surgery and group B (n = 35) with no history of cardiac surgery. Doses of intranasal DEX were analyzed by up-down sequential allocation at an initial dose of 2.3 μg/kg and an increase in steps of 0.2 μg/kg. Intranasal DEXED50 values were analyzed by the up-and-down method of Dixon-Massey and probit regression to determine ED50 and 95% confidence interval (CI) for sedation. The time to effective sedation, time to regaining consciousness, vital signs, oxygen saturation, time of performing TTE, clinical adverse effects, and characteristics of regaining consciousness were compared between the two groups.

Results

ED50 of intranasal DEX sedation was 2.530 μg/kg (95% CI, 1.657-4.156) in group A and 2.500 μg/kg (95% CI, 1.987-3.013) in group B. There was no significant difference in sedation onset time and time to regaining consciousness between the two groups. Additionally, no significant adverse hemodynamic or hypoxemic effect was observed. There was no significant difference in sedation-onset time and wake-up time between the two groups (15 ± 4 min vs.16 ± 5 min; 50 ± 11 min vs.48 ± 10 min). This trial is registered with the China Clinical Trials Registry (ChiCTR-IOR-1800015038).

Conclusions

ED50 of intranasal DEX sedation for TTE is similar in children with and without a history of cardiac surgery for cCHD.

COVID-19 in Pediatric Patients: A Focus on CHD Patients

Coronavirus disease 2019 (COVID-19) is a global pandemic caused by SARS-CoV-2 virus. As of the 30th of September 2020, around 34,000,000 cases have been reported globally. Pediatrics with underlying congenital heart disease represent a small yet a critical proportion of these patients. In general, the majority of infected children experience mild to moderate disease with significant interindividual variability in laboratory and radiographic findings. Nevertheless, in healthy children with COVID-19, cardiac involvement has been documented and is attributed to various causes. Myocarditis, arrhythmias, cardiogenic shock, and serious multisystem inflammatory syndrome in children are all encountered. Since COVID-19 is a recent novel disease and based on previous experience with respiratory infections, children with underlying congenital heart disease should be given special attention. To date, little data is available about COVID-19 presentation, complications, and appropriate treatment in this population. However, variable and inconsistent disease presentation and severity have been observed. This paper discusses COVID-19 course of illness in pediatric population with a special emphasis on the cardiac manifestations of the disease in healthy population and also on the disease course in congenital heart disease patients in particular.

Retinal microvasculature impairment in patients with congenital heart disease investigated by optical coherence tomography angiography

Importance

A high prevalence of retinal abnormalities have been reported in congenital heart disease (CHD), but quantitative analysis of retinal vasculature is scarce. Optical coherence tomography angiography (OCTA) is a noninvasive method to quantitatively assess the retinal microvasculature.

Background

To investigate the retinal microvasculature changes in CHD patients by using OCTA.

Design

Cross‐sectional study.

Participants

A total of 158 participants including 57 cyanotic CHD (CCHD) patients, 60 acyanotic CHD (ACHD) patients and 41 control subjects were included.

Methods

All participants underwent a comprehensive ophthalmologic examination, including refraction measurement, intraocular pressure measurement and OCTA.

Main Outcome Measures

Vessel density (VD) was measured within the radial peripapillary capillary (RPC), superficial capillary plexus (SCP) and deep capillary plexus (DCP) of the macula.

Results

CCHD patients had significantly lower VD in the RPC, SCP and DCP (all P < .01) compared to control subjects, and significantly lower VD in the RPC and DCP (both P < .05) compared to ACHD patients. Besides, among the CHD group, VD in the RPC was positively correlated with oxygen saturation (whole image, ρ = 0.45; peripapillary, ρ = 0.48) and negatively correlated with haematocrit (whole image, ρ = 0.55; peripapillary, ρ = 0.55) (all P < .001).

Conclusions and Relevance

Retinal VD might be a surrogate to reflect the effect of chronic systemic hypoxemia in CHD patients. OCTA could be a convenient and noninvasive tool to evaluate the retinal structure and function in CHD patients.

Congenital heart diseases: genetics, non-inherited risk factors, and signaling pathways

Background

Congenital heart diseases (CHDs) are the most common congenital anomalies with an estimated prevalence of 8 in 1000 live births. CHDs occur as a result of abnormal embryogenesis of the heart. Congenital heart diseases are associated with significant mortality and morbidity. The damage of the heart is irreversible due to a lack of regeneration potential, and usually, the patients may require surgical intervention. Studying the developmental biology of the heart is essential not only in understanding the mechanisms and pathogenesis of congenital heart diseases but also in providing us with insight towards developing new preventive and treatment methods.

Main body

The etiology of congenital heart diseases is still elusive. Both genetic and environmental factors have been implicated to play a role in the pathogenesis of the diseases. Recently, cardiac transcription factors, cardiac-specific genes, and signaling pathways, which are responsible for early cardiac morphogenesis have been extensively studied in both human and animal experiments but leave much to be desired. The discovery of novel genetic methods such as next generation sequencing and chromosomal microarrays have led to further study the genes, non-coding RNAs and subtle chromosomal changes, elucidating their implications to the etiology of congenital heart diseases. Studies have also implicated non-hereditary risk factors such as rubella infection, teratogens, maternal age, diabetes mellitus, and abnormal hemodynamics in causing CHDs.

These etiological factors raise questions on multifactorial etiology of CHDs. It is therefore important to endeavor in research based on finding the causes of CHDs. Finding causative factors will enable us to plan intervention strategies and mitigate the consequences associated with CHDs. This review, therefore, puts forward the genetic and non-genetic causes of congenital heart diseases. Besides, it discusses crucial signaling pathways which are involved in early cardiac morphogenesis. Consequently, we aim to consolidate our knowledge on multifactorial causes of CHDs so as to pave a way for further research regarding CHDs.

Conclusion

The multifactorial etiology of congenital heart diseases gives us a challenge to explicitly establishing specific causative factors and therefore plan intervention strategies. More well-designed studies and the use of novel genetic technologies could be the way through the discovery of etiological factors implicated in the pathogenesis of congenital heart diseases.