Potential effects of environmental chemical contamination in congenital heart disease

Computational simulations aided prioritization of genomic targets for congenital heart disease (CHD) against developmental toxicity

The determination of developmental toxicity (DT) is an emerging approach to investigate the environmental factors contributing to the development of congenital heart disease (CHD). However, the molecular interactions between these toxicants and cardiac-specific genes, along with the mechanisms, are not yet fully understood. This innovative study employed advanced in-silico techniques, such as protein-protein interaction (PPI) profiling, network analysis and molecular docking and dynamics simulations, to prioritize genomic targets and their associated toxicants. The study constructed a PPI network for CHD and identified key proteins includings GATA4, GATA6, NKX2-5, TBX5, MYH6, MYH11, TLL1, ANKRD1, CFC1, CRELD1, ZIC3, ACTC1, TBX20, TBX1, and HAND2. Fourteen maternal toxicants were reviewed and validated as potential causes of developmental toxicity using the Comparative Toxicogenomics Database (CTD). The minimum binding affinities of "Benzo[a]pyrene-7,8-diol-9,10-epoxide (BPDE)" against proteins TBX20, TLL1, NKX2-5, HAND2, ZIC3, and ACTC1, were -9.6, -9.5, -8.8, -8.7, -8.7, and -8.5 (kcal/mol), respectively compared to other toxicants. The residues PHE425 of TBX20 and PHE235 of TLL1 illustrated a strong bonding pattern with BPDE and demonstrated lower root mean square fluctuation (RMSF). Additionally, the compound it was found to inhibit hERG II channels, which could imply potential cardio-toxic effects. The study revealed that environmental toxicants during early pregnancy could inhibit the expression of prioritized heart developmental genes, highlighting the need for further in-vitro and in-vivo validation.

Transthoracic echocardiographic assessment of ventricular function in functional single ventricle: a comprehensive review

BACKGROUND

Functional single ventricle represents a complex congenital cardiac malformation where ventricular function directly impacts patients' quality of life and prognosis. Accurate assessment of ventricular function in FSV patients is crucial for treatment planning, surgical intervention, and monitoring therapeutic efficacy.

MAIN TEXT

Echocardiography, as a non-invasive, readily available, and real-time cardiac imaging modality, has emerged as the preferred method for evaluating functional single ventricle ventricular function. With continuous advancement and innovation in echocardiographic technology, methods for evaluating functional single ventricle ventricular function have become increasingly diverse and refined. This review synthesizes recent research developments in echocardiographic assessment of functional single ventricle ventricular function and analyzes the advantages, limitations, and future applications of various techniques.

CONCLUSION

Strain and strain rate derived from two-dimensional speckle tracking imaging have progressively entered clinical application, demonstrating substantial potential as crucial parameters for evaluating single ventricular function. Emerging technologies, including three-dimensional speckle tracking imaging and non-invasive pressure-strain loops, show promise for contributing to multi-dimensional, integrated assessment as research continues to advance.

Exposure to Endocrine-Disrupting Chemicals and Congenital Heart Diseases: The Pooled Results Based on the Current Evidence

The relationships between maternal exposure to endocrine-disrupting chemicals (EDCs) and congenital heart diseases (CHD) are not elucidated yet. The exposure levels of EDCs are generally estimated based on self-reported questionnaires or occupational exposure evaluations in the literature. Therefore, a study based on epidemiological data from human biospecimens is required to provide stronger evidence between maternal exposure to EDC and CHD. Embase, Pubmed, Scopus, and the Cochrane Library databases were searched for related research which provided risk estimates regarding the relationships between maternal EDC exposure and CHD in human offspring. Baseline characteristics and outcomes of CHD were extracted from each included study. Odds ratios (ORs) with 95% confidence intervals (CIs) were pooled to calculate the overall estimates of CHD. Subgroup and meta-regression analyses were performed to identify the sources of heterogeneity. Bootstrapping techniques were used in analyses where several studies originated from a similar population. A total of seventeen studies were involved in the meta-analyses. Maternal EDC exposure was significantly related to CHD in offspring (OR 2.15; 95%CI 1.64 to 2.83). EDC exposure was significantly associated with septal defects (OR 2.34; 95%CI 1.77 to 3.10), conotruncal defects (OR 2.54; 95%CI 1.89 to 3.43), right ventricular outflow tract obstruction (OR 2.65; 95%CI 1.73 to 4.07), left ventricular outflow tract obstruction (OR 3.58; 95%CI 2.67 to 4.79), anomalous pulmonary venous return (OR 2.31; 95%CI 1.34 to 4.00), and other heart defects (OR 2.49; 95%CI 1.75 to 3.54). In addition, maternal exposure to heavy metals, which included lead (OR 2.19; 95%CI 1.29 to 3.71), cadmium (OR 1.81; 95%CI 1.28 to 2.56), mercury (OR 2.23; 95%CI 1.13 to 4.44), and manganese (OR 2.65; 95%CI 1.48 to 4.74), increased risks for CHD significantly. In conclusion, based on the latest evidence, maternal EDC exposure may increase CHD risks in human offspring, especially in heavy metal exposure conditions.

Pulmonary vascular disease, environmental pollution, and climate change

Pollution and climate change constitute a combined, grave and pervasive threat to humans and to the life-support systems on which they depend. Evidence shows a strong association between pollution and climate change on cardiovascular and respiratory diseases, and pulmonary vascular disease (PVD) is no exception. An increasing number of studies has documented the impact of environmental pollution and extreme temperatures on pulmonary circulation and the right heart, on the severity and outcomes of patients with pulmonary arterial hypertension and chronic thromboembolic pulmonary hypertension (PH), on the incidence of pulmonary embolism, and the prevalence and severity of diseases associated with PH. Furthermore, the downstream consequences of climate change impair health care systems' accessibility, which could pose unique obstacles in the case of PVD patients, who require a complex and sophisticated network of health interventions. Patients, caretakers and health care professionals should thus be included in the design of policies aimed at adaptation to and mitigation of current challenges, and prevention of further climate change. The purpose of this review is to summarize the available evidence concerning the impact of environmental pollution and climate change on the pulmonary circulation, and to propose measures at the individual, healthcare and community levels directed at protecting patients with PVD.

Environmental Signals

Environmental factors have long been known to play a role in the pathogenesis of congenital heart disease (CHD), but this has not been a major focus of research in the modern era. Studies of human exposures and animal models demonstrate that demographics (age, race, socioeconomic status), diseases (e.g., diabetes, hypertension, obesity, stress, infection, high altitude), recreational and therapeutic drug use, and chemical exposures are associated with an increased risk for CHD. Unfortunately, although studies suggest that exposures to these factors may cause CHD, in most cases, the data are not strong, are inconclusive, or are contradictory. Although most studies concentrate on the effects of maternal exposure, paternal exposure to some agents can also modify this risk. From a mechanistic standpoint, recent delineation of signaling and genetic controls of cardiac development has revealed molecular pathways that may explain the effects of environmental signals on cardiac morphogenesis and may provide further tools to study the effects of environmental stimuli on cardiac development. For example, environmental factors likely regulate cellular signaling pathways, transcriptional and epigenetic regulation, proliferation, and physiologic processes that can control the development of the heart and other organs. However, understanding of the epidemiology and risk of these exposures and the mechanistic basis for any effects on cardiac development remains incomplete. Further studies defining the relationship between environmental exposures and human CHD and the mechanisms involved should reveal strategies to prevent, diagnose, and treat CHD induced by environmental signals.

Early Abortions and Congenital Malformations: A Comparison Between Agricultural and Nonagricultural Areas in the State of São Paulo/Brazil

INTRODUCTION

Areas with higher agricultural production have higher rates of abortion and malformation, probable related to pesticides.

OBJECTIVE

To compare the rates of early abortion and fetal malformation in agricultural and nonagricultural areas.

METHOD

A survey was carried out on fetal deaths in children weighing less than 500 g or gestational age less than 22 weeks and fetal malformations in live births.

RESULTS

From 1996 to 2018, there was an increase in the rates of abortion and, albeit to a lesser extent, malformation. The areas of greater agricultural production have higher rates of fetal mortality and malformation than the others.

CONCLUSIONS

The study suggests that areas with higher use of pesticides have higher rates of abortion and fetal malformations than the others, requiring further observational studies, reducing confounders inherent to the ecological study.

Maternal environmental, occupational, and urinary metabolite levels of benzene compounds and their association with congenital heart diseases in offspring: a case‒control study in China

The conclusions about the association of maternal pregnancy environment, occupation, and benzene compounds with fetal CHD are not entirely consistent. Eight hundred seven CHD cases and 1008 controls were included in this study. All occupations were classified and coded against the Occupational Classification Dictionary of the People's Republic of China (2015 version). Logistic regressions were used to explore the correlation among environmental factors, occupation types, and CHDs in offspring. We found that living near public facilities and having exposure to chemical reagents and hazardous substances were significant risk factors for CHDs in offspring. We found that offspring of mothers who worked in agriculture and similar work during pregnancy suffered from CHD. The risk of all CHDs in the offspring of pregnant women working in production manufacturing and related work was significantly higher than that in unemployed pregnant women, the risk was also observed in 4 subtypes of CHDs. We compared the concentrations of the five metabolite (MA, mHA, HA, PGA, and SPMA) levels of benzene compounds in the urine of mothers in case and control groups and found no significant differences. Our study suggests that maternal exposure during pregnancy and certain environmental and occupational conditions are risk factors for CHD in offspring, but did not support an association between concentrations of metabolites of benzene compounds in the urine of pregnant women and CHDs in their offspring.

Epigenetic Evaluation of the TBX20 Gene and Environmental Risk Factors in Mexican Paediatric Patients with Congenital Septal Defects

The TBX20 gene has a key role during cardiogenesis, and it has been related to epigenetic mechanisms in congenital heart disease (CHD). The purpose of this study was to assess the association between DNA methylation status and congenital septal defects. The DNA methylation of seven CpG sites in the TBX20 gene promoter was analyzed through pyrosequencing as a quantitative method in 48 patients with congenital septal defects and 104 individuals with patent ductus arteriosus (PDA). The average methylation was higher in patients than in PDA (p < 0.001). High methylation levels were associated with a higher risk of congenital septal defects (OR = 4.59, 95% CI = 1.57-13.44, p = 0.005). The ROC curve analysis indicated that methylation of the TBX20 gene could be considered a risk marker for congenital septal defects (AUC = 0.682; 95% CI = 0.58-0.77; p < 0.001). The analysis of environmental risk factors in patients with septal defects and PDA showed an association between the consumption of vitamins (OR = 0.10; 95% CI = 0.01-0.98; p = 0.048) and maternal infections (OR = 3.10; 95% CI = 1.26-7.60; p = 0.013). These results suggest that differences in DNA methylation of the TBX20 gene can be associated with septal defects.

Early prenatal exposure to air pollutants and congenital heart disease: a nested case-control study

BACKGROUND

Congenital heart disease (CHD) is one of the most common congenital malformations in humans. Inconsistent results emerged in the existed studies on associations between air pollution and congenital heart disease. The purpose of this study was to evaluate the association of gestational exposure to air pollutants with congenital heart disease, and to explore the critical exposure windows for congenital heart disease.

METHODS

The nested case-control study collected birth records and the following health data in Tianjin Women and Children's Health Center, China. All of the cases of congenital heart disease from 2013 to 2015 were selected matching five healthy controls for each case. Inverse distance weighting was used to estimate individual exposure based on daily air pollution data. Furthermore, the conditional logistic regression with distributed lag non-linear model was performed to identify the association between gestational exposure to air pollution and congenital heart disease.

RESULTS

A total of 8,748 mother-infant pairs were entered into the analysis, of which 1,458 infants suffered from congenital heart disease. For each 10 µg/m³ increase of gestational exposure to PM_2.5, the ORs (95% confidence interval, 95%CI) ranged from 1.008 (1.001-1.016) to 1.013 (1.001-1.024) during the 1^st-2^nd gestation weeks. Similar weak but increased risks of congenital heart disease were associated with O₃ exposure during the 1^st week and SO₂ exposure during 6^th-7^th weeks in the first trimester, while no significant findings for other air pollutants.

CONCLUSIONS

This study highlighted that gestational exposure to PM_2.5, O₃, and SO₂ had lag effects on congenital heart disease. Our results support potential benefits for pregnancy women to the mitigation of air pollution exposure in the early stage, especially when a critical exposure time window of air pollutants may precede heart development.

Fine particulate matter induces heart defects via AHR/ROS-mediated endoplasmic reticulum stress

Accumulating body of evidence indicates that exposure to fine particulate matter (PM_2.5) is closely associated with congenital heart disease in the offspring, but the underlying molecular mechanisms remain to be elucidated. We previously reported that extractable organic matter (EOM) from PM_2.5 induces reactive oxygen species (ROS) overproduction by activating aromatic hydrocarbon receptor (AHR), leading to heart defects in zebrafish embryos. We hypothesized that endoplasmic reticulum (ER) stress might be elicited by the excessive ROS production and thereby contribute to the cardiac developmental toxicity of PM_2.5. In this study, we examined the effects of EOM on endoplasmic reticulum (ER) stress, apoptosis, and Wnt signal pathway in zebrafish embryos, and explored their roles in EOM-induced heart defects. Our results showed that 4-Phenylbutyric acid (4-PBA), a pharmaceutical inhibitor of ER stress, significantly attenuated the EOM-elevated heart malformation rates. Moreover, EOM upregulated the expression levels of ER stress marker genes including CHOP and PDI in the heart of zebrafish embryos, which were counteracted by genetic or pharmaceutical inhibition of AHR activity. The ROS scavenger N-Acetyl-l-cysteine (NAC) also abolished the EOM-induced ER stress. We further demonstrated that both 4-PBA and CHOP genetic knockdown rescued the PM_2.5-induced ROS overproduction, apoptosis and suppression of Wnt signaling. In conclusion, our results indicate that PM_2.5 induces AHR/ROS-mediated ER stress, which leads to apoptosis and Wnt signaling inhibition, ultimately resulting in heart defects.

Association between maternal smoke exposure and congenital heart defects from a case-control study in China

There is a gap in knowledge how maternal exposure to environmental tobacco smoke (ETS) is associated with offspring congenital heart defects (CHDs). In this case-control study, we collected data on 749 fetuses with CHDs and 880 fetuses without any congenital anomalies to examine the association of maternal ETS with fetal CHDs and the potentially moderating effect by maternal hazardous and noxious substances (HNS), periconceptional folate intake and paternal smoking. Maternal exposure to ETS in first trimester was associated with increased risk of CHDs in a dose-response gradient, with the AORs (95% CI) were1.38 (1.00-1.92), 1.60 (1.07-2.41), and 4.94 (2.43-10.05) for ETS < 1 h/day, 1-2 h/day, and ≥ 2 h/day, respectively. With the doubly unexposed group as reference categories, AORs for maternal ETS exposure ≥ 2 h/day in the absence of folate intake, in the presence of HNS exposure or paternal smoking, were 7.21, 11.43, and 8.83, respectively. Significant additive interaction between ETS exposure and maternal folate intake on CHDs was detected. Maternal ETS exposure during first trimester may increase the risk of offspring CHDs in a dose-response shape, and such effect may be modified by maternal folate intake or other potential factors.

Questionnaire-based exposome-wide association studies (ExWAS) reveal expected and novel risk factors associated with cardiovascular outcomes in the Personalized Environment and Genes Study

While multiple factors are associated with cardiovascular disease (CVD), many environmental exposures that may contribute to CVD have not been examined. To understand environmental effects on cardiovascular health, we performed an exposome-wide association study (ExWAS), a hypothesis-free approach, using survey data on endogenous and exogenous exposures at home and work and data from health and medical histories from the North Carolina-based Personalized Environment and Genes Study (PEGS) (n = 5015). We performed ExWAS analyses separately on six cardiovascular outcomes (cardiac arrhythmia, congestive heart failure, coronary artery disease, heart attack, stroke, and a combined atherogenic-related outcome comprising angina, angioplasty, atherosclerosis, coronary artery disease, heart attack, and stroke) using logistic regression and a false discovery rate of 5%. For each CVD outcome, we tested 502 single exposures and built multi-exposure models using the deletion-substitution-addition (DSA) algorithm. To evaluate complex nonlinear relationships, we employed the knockoff boosted tree (KOBT) algorithm. We adjusted all analyses for age, sex, race, BMI, and annual household income. ExWAS analyses revealed novel associations that include blood type A (Rh-) with heart attack (OR[95%CI] = 8.2[2.2:29.7]); paint exposures with stroke (paint related chemicals: 6.1[2.2:16.0], acrylic paint: 8.1[2.6:22.9], primer: 6.7[2.2:18.6]); biohazardous materials exposure with arrhythmia (1.8[1.5:2.3]); and higher paternal education level with reduced risk of multiple CVD outcomes (stroke, heart attack, coronary artery disease, and combined atherogenic outcome). In multi-exposure models, trouble sleeping and smoking remained important risk factors. KOBT identified significant nonlinear effects of sleep disorder, regular intake of grapefruit, and a family history of blood clotting problems for multiple CVD outcomes (combined atherogenic outcome, congestive heart failure, and coronary artery disease). In conclusion, using statistics and machine learning, these findings identify novel potential risk factors for CVD, enable hypothesis generation, provide insights into the complex relationships between risk factors and CVD, and highlight the importance of considering multiple exposures when examining CVD outcomes.

Potential occupational exposure of parents to endocrine disrupting chemicals, adverse birth outcomes, and the modification effects of multi-vitamins supplement and infant sex

BACKGROUND

Maternal occupational exposure to endocrine disrupting chemicals (EDCs) may have adverse effect on birth outcomes. However, little is known about paternal EDCs exposure and the combined effect of parental exposure on birth outcomes.

OBJECTIVES

To assess the effects of both maternal and paternal occupational EDCs exposure on adverse birth outcomes, and further explore if multi-vitamins supplement and infant sex modify the association.

METHODS

We conducted a prospective cohort study of 5421 mother-father-newborn groups in Guangzhou, China. A questionnaire informed by a job exposure matrix (JEM) was applied to collect parental occupational EDCs exposure based on the type of work performed. We used logistic regression to estimate association between parental EDCs exposure and birth outcomes (including preterm birth (PTB), low birth weight (LBW), birth defects and congenital heart defects (CHD)). Stratified analyses and Cochran Q tests were performed to assess the modifying effect of maternal multi-vitamins supplement use and infant sex.

RESULTS

Compared with mothers unexposed, we found that mothers those exposed to EDCs were associated with increased odds of birth defects (aOR=1.70, 95% confidence interval (CI): 1.10-2.62), especially for those exposed for > 1.5 years (aOR= 3.00, 95% CIs: 1.78-5.03), or those with directly occupational exposed to EDCs (aOR= 2.94, 95% CIs: 1.72-5.04). Maternal exposure for > 1.5 years and direct exposure increased the risk of CHD, with aORs of 2.47 (1.21-5.02) and 2.79 (1.37-5.69), respectively. Stronger adverse effects were also observed when mothers and fathers were both exposed to EDCs. Paternal occupational EDCs exposure and exposure ≤ 1.5 years was associated with increased odds of LBW, with aORs of 2.14 (1.63-2.79) and 1.54 (1.10-2.15), respectively. When stratified by multi-vitamins supplement and infant sex, we observed slightly stronger effects for maternal exposure on birth defects/CHD as well as paternal EDCs exposure on PTB and LBW, among those without multi-vitamins supplement and among male babies, although the modification effects were not significant.

CONCLUSION

Maternal exposure to EDCs was associated with greater odds of birth defects and CHD, while paternal exposure was mainly associated with greater odds of LBW. These effects tend to be stronger among mothers without multi-vitamins supplement and among male babies.

Maternal Viral Infection in Early Pregnancy and Risk of Congenital Heart Disease in Offspring: A Prospective Cohort Study in Central China

PURPOSE

To examine the associations of maternal virus infection in early pregnancy with risk of offspring congenital heart disease (CHD) and its seven common subtypes including atrial septal defect, ventricular septal defect, atrioventricular septal defect, patent ductus arteriosus, Tetralogy of Tallot, pulmonary stenosis, and transposition of the great arteries.

PATIENTS AND METHODS

A prospective cohort study was conducted in Central China. A total of 44,048 pregnant women with singleton pregnancies at 8-14 gestational weeks were finally included and followed to 3 months postpartum. Serum was tested for virus infection including hepatitis B virus (HBV), coxsackievirus-B, human cytomegalovirus (HCMV), herpes simplex virus (HSV), and rubella virus. Multivariable modified Poisson regression models were used to estimate the relative risks (RRs) of all CHDs as well as seven common subtypes of CHD in offspring of pregnant women with different types of virus infection in early pregnancy, adjusting for confounders identified by directed acyclic graphs.

RESULTS

At the end of follow-up, 564 births were diagnosed with CHD. Multivariable analyses showed that the presence of maternal viral infection in early pregnancy was independently associated with increased risks of CHD in offspring, with an adjusted relative risk of 2.21 (95% CI: 1.66-2.95) for HBV infection, 2.21 (95% CI: 1.63-3.00) for coxsackievirus-B infection, 3.12 (95% CI: 2.44-3.98) for HCMV infection, and 2.62 (95% CI: 1.95-3.51) for rubella virus infection. More specifically, the offspring of pregnant women with HCMV infection had the highest increased risk of patent ductus arteriosus (RR=10.50, 95% CI: 6.24-17.66). These findings persisted in analyses that were further adjusted for the other virus of interest in this study.

CONCLUSION

Our study proposed evidence that maternal virus infection in early pregnancy, including HBV, coxsackievirus-B, HCMV, and rubella virus, was implicated in CHD, although more studies remain needed to verify the results, especially associations in specific CHD phenotypes.

Maternal air pollution exposure and neonatal congenital heart disease: A multi-city cross-sectional study in eastern China

OBJECTIVE

To examine the association between air pollution and neonatal congenital heart disease (CHD), and evaluate the cumulative burden of CHD attributed to above certain level for ambient air pollution exposure.

METHODS

We identified newborns who were diagnosed as CHD by echocardiography in Network Platform for Congenital Heart Disease (NPCHD) from January 2019 to December 2020 in 11 cities eastern China. The exposure lag response relationship between air pollutants (PM_2.5, PM₁₀, SO₂, NO₂, CO, and O₃) concentration and CHDs was calculated by the distributed lag nonlinear model (DLNM). We further calculated the cumulative risk ratios (CRRs) of each air pollutant above reference concentrations on CHDs.

RESULTS

A total of 5904 CHDs from 983, 523 newborns were enrolled in this study. A 10 μg/m³ increase in PM_2.5, PM₁₀, SO₂, NO₂, CO and O₃ exposure was associated with an increased risk of higher CHD incident RR = 1.025, 95% CI: 1.016-1.038 for PM_2.5 in the third trimester, RR = 1.001, 95% CI: 1.000-1.002 for PM₁₀ in the third trimester, 1.020, 95%CI: 1.004-1.036 for NO₂ in the third trimester, RR = 1.001, 95%CI: 1.000-1.002 for O₃ in the first trimester, all P value < 0.05). Cumulative effect curves of PM_2.5, PM₁₀, SO₂, NO₂, CO, and O₃ were observed as sub-linear with a maximum of 1.876 (95%CI:1.220-2.886), 1.973 (95%CI:1.477,2.637), 2.169 (95%CI:1.347-3.493), 2.902 (95%CI:1.859-4.530), 1.398 (95%CI:1.080-1.809), 2.691 (95%CI:1.705-4.248), respectively. Significant associations were observed for air pollutants and CHDs in cities with higher average education years and babies concepted in cold season.

CONCLUSIONS

Our findings could provide growing evidence regarding the adverse health effects of air pollution on CHD, thereby strengthening the hypothesis that air pollutants have harmful impacts on cardiac development. Further studies are needed to verify the associations.

Parental risk factors associated with congenital heart disease in a Thai population: multivariable analysis

Background

Congenital heart diseases (CHDs) are the most common types of birth defects and contribute to a large proportion of infant morbidities and mortalities worldwide. These defects may require multiple surgical interventions impacting the infant's quality of life.

Objectives

To identify risk factors associated with CHD in a population of Thai children.

Methods

We conducted a case-control study of patients attending the Pediatric Clinic, Naresuan University Hospital, Thailand. We included data from pediatric patients diagnosed with CHDs as cases, and patients without cardiovascular abnormalities as controls. Risk data were collected from July 2019 to April 2020 using face-to-face interviews. Multiple logistic regression was used to analyze parental factors associated with CHDs.

Results

We included 249 cases classified into 2 groups according to severity and 304 patients as controls. For those less-severely affected (155 patients, 62.2%), ventricular septal defect (27.7%) was the most prevalent, whereas for those with severe CHDs, tetralogy of Fallot was the most prevalent (14.0%). There was no difference in sex distribution or maternal obstetric history between the groups. In multivariable analysis, a family history of CHDs (adjusted odds ratio [AOR] 4.67, 95% confidence interval (CI) 1.61-13.57, P = 0.005) and maternal exposure to second-hand cigarette smoke (AOR 1.58, 95% CI 1.03-2.42, P = 0.002) were identified as significant risk factors for CHDs.

Conclusion

A family history of CHDs and maternal exposure to second-hand cigarette smoke are associated with having offspring with CHDs in the population studied. These findings help us to encourage affected parents to obtain a fetal echocardiogram.

Children's Environmental Health: A Systems Approach for Anticipating Impacts from Chemicals

Increasing numbers of chemicals are on the market and present in consumer products. Emerging evidence on the relationship between environmental contributions and prevalent diseases suggests associations between early-life exposure to manufactured chemicals and a wide range of children’s health outcomes. Using current assessment methodologies, public health and chemical management decisionmakers face challenges in evaluating and anticipating the potential impacts of exposure to chemicals on children’s health in the broader context of their physical (built and natural) and social environments. Here, we consider a systems approach to address the complexity of children’s environmental health and the role of exposure to chemicals during early life, in the context of nonchemical stressors, on health outcomes. By advancing the tools for integrating this more complex information, the scope of considerations that support chemical management decisions can be extended to include holistic impacts on children’s health.

Lufenuron induces reproductive toxicity and genotoxic effects in pregnant albino rats and their fetuses

Insecticides and other agrochemicals have become indispensable components of the agricultural system to ensure a notable increase in crop yield and food production. As a natural consequence, chemical residues result in significantly increased contamination of both terrestrial and aquatic ecosystems. The present study evaluated the teratogenic, genotoxic, and oxidative stress effects of residual-level lufenuron exposure on pregnant rats during the organogenesis gestational period of both mother and fetus. The tested dams were divided into three groups; control (untreated), low-dose group (orally administered with 0.4 mg/kg lufenuron) and high-dose group (orally administered with 0.8 mg/kg lufenuron). The dams of the two treatment groups showed teratogenic abnormalities represented by the asymmetrical distribution of fetuses in both uterine horns, accompanied by observed resorption sites and intensive bleeding in the uterine horns, whereas their fetuses suffered from growth retardation, morphologic malformations, and skeletal deformations. Histologic examination of the liver and kidney tissues obtained from mothers and fetuses after lufenuron exposure revealed multiple histopathologic changes. DNA fragmentation and cell cycle perturbation were also detected in the liver cells of lufenuron-treated pregnant dams and their fetuses through comet assay and flow cytometry, respectively. Moreover, lufenuron-induced oxidative stress in the liver of mothers and fetuses was confirmed by the increased malondialdehyde levels and decreased levels of enzymatic antioxidants (glutathione peroxidase and superoxide dismutase). Taken together, it can be concluded that lufenuron has a great potential in exerting teratogenic, genotoxic, and oxidative stresses on pregnant rats and their fetuses upon chronic exposure to residual levels during the organogenesis gestational period. The obtained results in the present study imply that women and their fetuses may have the same risk.

Tebuconazole induces ROS-dependent cardiac cell toxicity by activating DNA damage and mitochondrial apoptotic pathway

Tebuconazole (TEB) is a common triazole fungicide that is widely used throughout the world in agriculture applications. We previously reported that TEB induces cardiac toxicity in rats. The aim of this study was to investigate the underlying mechanism of the toxicity induced by TEB in cardiac cells. TEB induced dose-dependent cell death in H9c2 cardiomyoblasts and in adult rat ventricular myocytes (ARVM). The comet assay and western blot analysis showed a concentration-dependent increase in DNA damage and in p53 and p21 protein levels 24 h after TEB treatment. Our findings also showed that TEB triggered the mitochondrial pathway of apoptosis as evidenced by a loss of mitochondrial transmembrane potential (ΔΨm), an increase in Bax/Bcl-2 ratio, an activation of caspase-9 and caspase-3, a cleavage of poly (ADP-ribose) polymerase (PARP) and an increase in the proportion of cells in the sub-G1 phase. In addition, TEB promoted ROS production in cardiac cells and consequently increased the amounts of MDA, the end product of lipid peroxidation. Treatment of cardiomyocytes with the ROS scavenger N-acetylcysteine reduced TEB-induced DNA damage and activation of the mitochondrial pathway of apoptosis. These results indicate that the genotoxic and cytotoxic effects of TEB are mediated through a ROS-dependent pathway in cardiac cells.

Maternal occupational exposure and congenital heart defects in offspring

Objectives Congenital heart defects (CHD) are the most prevalent congenital anomalies. This study aims to examine the association between maternal occupational exposures to organic and mineral dust, solvents, pesticides, and metal dust and fumes and CHD in the offspring, assessing several subgroups of CHD. Methods For this case-control study, we examined 1174 cases with CHD from EUROCAT Northern Netherlands and 5602 controls without congenital anomalies from the Lifelines cohort study. Information on maternal jobs held early in pregnancy was collected via self-administered questionnaires, and job titles were linked to occupational exposures using a job exposure matrix. Results An association was found between organic dust exposure and coarctation of aorta [adjusted odds ratio (OR _adj) 1.90, 95% confidence interval (CI) 1.01-3.59] and pulmonary (valve) stenosis in combination with ventricular septal defect (OR _adj2.68, 95% CI 1.07-6.73). Mineral dust exposure was associated with increased risk of coarctation of aorta (OR _adj2.94, 95% CI 1.21-7.13) and pulmonary valve stenosis (OR _adj1.99, 95% CI 1.10-3.62). Exposure to metal dust and fumes was infrequent but was associated with CHD in general (OR _adj2.40, 95% CI 1.09-5.30). Exposure to both mineral dust and metal dust and fumes was associated with septal defects (OR _adj3.23, 95% CI 1.14-9.11). Any maternal occupational exposure was associated with a lower risk of aortic stenosis (OR _adj0.32, 95% CI 0.11-0.94). Conclusions Women should take preventive measures or avoid exposure to mineral and organic dust as well as metal dust and fumes early in pregnancy as this could possibly affect foetal heart development.

Maternal residential greenness and congenital heart defects in infants: A large case-control study in Southern China

BACKGROUND

Proximity to greenness has shown protective effects on coronary heart diseases by limiting exposure to environmental hazards, encouraging physical activity, and reducing mental stress. However, no studies have previously evaluated the impacts of greenness on congenital heart defects (CHDs). We examined the association between maternal residential greenness and the risks of CHDs.

METHODS

We conducted a case-control study (8042 children with major CHDs and 6887 controls without malformations) in 21 cities in Southern China, 2004 - 2016. CHDs cases were diagnosed and verified by obstetrician, pediatrician, or pediatric cardiologists, within one year. We estimated maternal residential greenness using satellite-derived normalized difference vegetation index (NDVI) in zones of 500 meters (m) and 1000 m surrounding participants' residences. Logistic regression models were used to assess NDVI-CHD relationships adjusting for confounders.

RESULTS

Interquartile range NDVI increases within 500 m or 1000 m were associated with odds ratios (OR) of 0.95 (95% confidence interval (CI): 0.92, 0.98) and 0.94 (95%CI: 0.91, 0.97) for total CHDs respectively. Air pollutants mediated 52.1% of the association. We also identified a protective threshold at 0.21 NDVI on CHD. Similar protective effects from greenness were found in most CHDs subtypes. The protective associations were stronger for fall, urban or permanent residents, higher household income maternal age ≤35 years of age, and high maternal education (ORs: ranged from 0.85 to 0.96).

CONCLUSION

Our findings suggest a beneficial effect of maternal residential greenness on CHDs. Further studies are needed to confirm our findings, which will help to refine preventive health and urban design strategies.

De novo congenital malformation frequencies in children from the Bryansk region following the Chernobyl disaster (2000-2017)

BACKGROUND

Ionizing radiation and chemical pollution can disrupt normal embryonic development and lead to congenital malformations and fetal death. We used official government statistical data for 2000-2017 to test the hypothesis that radioactive and chemical pollutants influenced the frequency of de novo congenital malformations in newborns of the Bryansk region of southwest Russia.

METHODS

A variety of statistical approaches were used to assess congenital malformation frequencies including the Shapiro-Wilk test, White's homoscedasticity test, Wilcoxon T-test, Spearman's rank correlation test, and the inversely proportional regression.

RESULTS

We found that the frequency of polydactyly, multiple congenital malformations, and the frequency of de novo congenital malformations in newborns were significantly higher (p = 0.001-0.054) in regions with elevated radioactive, chemical and combined contamination. Polydactyly, multiple congenital malformations, and the sum of all congenital malformations were 4.7-7.4 times, 2.5-6.8 times, and 3.5-4.6 times higher in contaminated regions in comparison with the control group. The combination of both radioactive and chemical pollutants led to significantly higher frequencies of multiple congenital malformations when compared to regions with only one pollutant (radiation alone: 2.2 times, p = 0.034; chemical pollutants alone: 1.9 times, p = 0.008) implying that the effects of these stressors were at minimum additive. Although there was a trend for decreasing frequencies of multiple congenital malformations during the 2000-2017 period in areas of combined pollution, the opposite was true for regions with radioactive or chemical pollutants alone. However, overall, our models suggest that the frequency of multiple congenital malformations in areas of combined pollution will significantly (p = 0.027) exceed the frequencies observed for regions containing radioactive or chemical pollutants alone by 39.6% and 45.7% respectively, by 2018-2023.

CONCLUSION

These findings suggest additive and potentially synergistic effects of radioactive and chemical pollutants on the frequencies of multiple congenital malformations in the Bryansk region of southwestern Russia.

Evaluation of interactive effects between paternal alcohol consumption and paternal socioeconomic status and environmental exposures on congenital heart defects

BACKGROUND

While the maternal risk factors on congenital heart defects (CHDs) have often been assessed, paternal contribution to CHDs, especially the joint effects of paternal risk factors on CHDs remain unknown. This study examined the major impacts of paternal alcohol consumption and its interaction (on multiplicative and additive scales) with paternal socioeconomic status (SES) and environmental exposures on CHDs in China.

METHODS

A population-based case-control study involving 4,726 singleton CHDs cases and 4,726 controls (without any malformation and matched on hospital, gender, and gestational age) was conducted in Guangdong, China, 2004-2014. Information on parental demographics, behavioral patterns, disease/medication, and environmental exposures (3 months before pregnancy) was collected through face-to-face interviews. Conditional logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (CIs) while controlling for all parental factors.

RESULTS

Paternal alcohol consumption was associated with an increased OR of CHDs (adjusted OR = 2.87, 95% CI: 2.25-3.65). Additionally, paternal smoking, industry occupation, organic solvent contact, virus infection and antibiotic use, living in rural areas, low household income, and migrant status were significantly associated with CHDs (ORs ranged: 1.42-4.44). Significant additive or multiplicative interactions were observed between paternal alcohol consumption and paternal smoking, industrial occupation, and low income on any CHDs (interaction contrast ratio [ICR] = 4.72, 95% CI: 0.96-8.47] and septal defects (ICRs ranged from 2.04 to 2.79, p < .05).

CONCLUSIONS

Paternal alcohol consumption and multiple paternal factors were significantly associated with CHDs in China. Paternal smoking and low SES factors modified paternal alcohol consumption-CHDs relationships. Further studies are needed to confirm these findings.

Maternal air pollution exposure associated with risk of congenital heart defect in pre-pregnancy overweighted women

OBJECTIVES

Prenatal exposure to air pollutant has been associated with congenital heart defect (CHD). However, no study has investigated this effect in pre-pregnancy overweighted women. This study aimed to evaluate gestational exposure to particulate pollutant (PM_2.5) and gaseous air pollutants (O₃ and NO₂) on the risk of CHD, and explore the potential effect modifiers including maternal age, pre-pregnancy BMI and pregestational diseases.

METHODS

In this birth cohort study, a total of 63,213 pregnant women in Foshan, China were initially recruited and followed from their first hospital visit for pregnancy to delivery during 2015-2019. CHD cases were confirmed by the records in hospital- and population- based birth defect surveillance systems. Air pollutant exposures were estimated by the daily concentrations measured in air monitoring stations in each participant's residential county. Mixed-effects regression models, adjusted for potential confounding factors were applied to estimate the associations between air pollutant and CHD during the first three months of the pregnancy.

RESULTS

A total of 985 (1.6%) newborns were identified as CHD cases. For each 10 μg/m³ increase in ambient O₃ during the 1st month, the OR values for CHD were 1.03 (95% CI: 0.94, 1.13) in pre-pregnancy normal weighted women and 1.24 (95% CI: 1.01, 1.53) in pre-pregnancy overweighted women. For each 10 μg/m³ increase in NO₂ during the 3rd month, the OR values for CHD were 1.09 (95% CI: 1.01, 1.18) in pre-pregnancy normal weighted women and 1.27 (95% CI: 1.07, 1.51) in pre-pregnancy overweighted women. No significant associations were found between PM_2.5 exposure and CHD in our analysis.

CONCLUSIONS

This study demonstrates that gaseous air pollutants (O₃ and NO₂) exposure during the cardiac embryogenesis period is associated with an increased risk of CHD, particularly for pre-pregnancy overweighted women.

Associations of maternal upper respiratory tract infection/influenza during early pregnancy with congenital heart disease in offspring: evidence from a case-control study and meta-analysis

Background

Evidences regarding the associations between maternal upper respiratory tract infection/influenza during pregnancy and the risk of congenital heart disease (CHD) is still controversial. This study was specifically designed to examine the associations by a case-control study and a meta-analysis of the published evidences and our finding.

Methods

A hospital-based case-control study involving 262 children with simple CHD and 262 children with complex CHD, along with 262 control children, was conducted through June, 2016 to December, 2017. All children were aged 0–2 years old. Furthermore, a meta-analysis based on both previously published studies and our case-control study was performed.

Results

In the case-control study, after adjusting for possible confounders, maternal upper respiratory tract infection/influenza during early pregnancy was found to be related to an increased risk of CHD (OR = 3.40 and 95% CI: 2.05–5.62 for simple CHD; OR = 2.39 and 95% CI: 1.47–3.88 for complex CHD). After a meta-analysis, the adverse impact was still kept significant (OR = 1.47 and 95% CI: 1.28–1.67 for simple CHD; OR = 1.44 and 95% CI: 1.14–1.75 for complex CHD). The very similar associations were also observed among single type of CHD, herein, ventricular septal defects (VSD) and tetralogy of fallot (TOF) in the case-control study. In the subsequent meta-analysis, however, the significant association only existed in VSD.

Conclusions

Although there is still conflicting in TOF, the results are overall consistent, which provide new enforced evidence that maternal upper respiratory tract infection/influenza during early pregnancy, in general, play an important role in the occurrence of CHD.

Prevalence of Congenital Anomalies in the Japan Environment and Children's Study

BACKGROUND

The aims of the present report were to estimate the prevalence of congenital anomalies (CAs) among infants in Japan using data from the Japan Environment and Children's Study (JECS) and to evaluate the validity of CA classification within JECS.

METHODS

Data on CAs were collected at delivery and at age 1 month from the medical records of 101,825 infants at 15 regional centers. The analyses focused on 61 CAs, selected on the basis of reported associations with environmental exposure. Prevalence per 10,000 pregnancies (including miscarriages, stillbirths, and live births) was stratified according to four reporting patterns (at delivery, at age 1 month, at either, and at both). To evaluate the accuracy of observed CA prevalence, the medical records of 179 cases from a single JECS regional center underwent independent, retrospective re-evaluation.

RESULTS

The prevalence of major CAs in four reporting patterns (at delivery, at age 1 month, at either, and at both) was 2.4, 2.6, 3.5, and 1.4 for myelomeningocele/spina bifida; 4.3, 4.2, 5.3, and 3.2 for cleft palate; 18.1, 17.4, 19.5, and 15.1 for cleft lip with or without cleft palate; 73.4, 100.3, 120.8, and 52.8 for congenital heart disease; and 10.5, 14.1, 15.0, and 9.6 for Down's syndrome, respectively. In the subsample re-evaluation, CA diagnoses were confirmed for 92.7%, 93.3%, 90.5%, and 97.8% of cases in the four reporting patterns (at delivery, at age 1 month, at either, and at both), respectively.

CONCLUSIONS

The present report generated reliable data concerning the prevalence of major CAs in JECS.

The Role of Non-Coding RNA in Congenital Heart Diseases

Cardiovascular development is a complex developmental process starting with the formation of an early straight heart tube, followed by a rightward looping and the configuration of atrial and ventricular chambers. The subsequent step allows the separation of these cardiac chambers leading to the formation of a four-chambered organ. Impairment in any of these developmental processes invariably leads to cardiac defects. Importantly, our understanding of the developmental defects causing cardiac congenital heart diseases has largely increased over the last decades. The advent of the molecular era allowed to bridge morphogenetic with genetic defects and therefore our current understanding of the transcriptional regulation of cardiac morphogenesis has enormously increased. Moreover, the impact of environmental agents to genetic cascades has been demonstrated as well as of novel genomic mechanisms modulating gene regulation such as post-transcriptional regulatory mechanisms. Among post-transcriptional regulatory mechanisms, non-coding RNAs, including therein microRNAs and lncRNAs, are emerging to play pivotal roles. In this review, we summarize current knowledge on the functional role of non-coding RNAs in distinct congenital heart diseases, with particular emphasis on microRNAs and long non-coding RNAs.

Prenatal exposure to PM2.5 and Congenital Heart Diseases in Taiwan

Gestational exposure to ambient air pollution has been associated with Congenital Heart Diseases (CHDs). However, only a few studies, with inconsistent results, have investigated the effects of PM_2.5 exposure during early pregnancy. This study aims to evaluate the association between prenatal exposure to PM_2.5 and CHDs occurrence. We selected 782 births reported to have CHDs between 2007 and 2014 from the Taiwanese Birth Registry and randomly selected 4692 controls without any birth defects using a population-based case-control design. Data of exposure to ambient air pollutants, mainly PM_2.5, PM₁₀, CO, SO₂, NO₂, and O₃ during weeks 3-8 of pregnancy were retrieved from air quality monitoring stations and interpolated to every township using ordinary kriging. We applied unconditional logistic regression models adjusted for potential confounders to evaluate the associations. The results revealed a positive correlation between increased PM_2.5 exposure (adjusted odds ratio [aOR] = 1.21, 95% confidence interval [CI] = 1.03-1.42, per interquartile range change = 13.4 μg/m³) during early pregnancy and overall CHDs occurrence. Furthermore, we found that atrial septal defect (aOR = 1.43, 95% CI = 1.01-2.02), endocardial cushion defect (aOR = 2.37, 95% CI = 1.01-5.58), and pulmonary artery and valve stenosis (aOR = 1.71, 95% CI = 1.06-2.78) were significantly associated with PM_2.5 exposures. No similar effects were observed for the other air pollutants. This study has demonstrated some positive associations between increased PM_2.5 exposure during the critical period of cardiac embryogenesis and certain CHDs occurrence.

The Role of Abnormal Placentation in Congenital Heart Disease; Cause, Correlate, or Consequence?

Congenital heart disease (CHD) is the most common birth defect, affecting ~1% of all live births (van der Linde et al., 2011). Despite improvements in clinical care, it is the leading cause of infant mortality related to birth defects (Yang et al., 2006) and burdens survivors with significant morbidity (Gilboa et al., 2016). Furthermore, CHD accounts for the largest proportion (26.7%) of birth defect-associated hospitalization costs—up to $6.1 billion in 2013 (Arth et al., 2017). Yet after decades of research with a primary focus on genetic etiology, the underlying cause of these defects remains unknown in the majority of cases (Zaidi and Brueckner, 2017). Unexplained CHD may be secondary to undiscovered roles of noncoding genetic, epigenetic, and environmental factors, among others (Russell et al., 2018). Population studies have recently demonstrated that pregnancies complicated by CHD also carry a higher risk of developing pathologies associated with an abnormal placenta including growth disturbances (Puri et al., 2017), preeclampsia (Auger et al., 2015; Brodwall et al., 2016), preterm birth (Laas et al., 2012), and stillbirth (Jorgensen et al., 2014). Both the heart and placenta are vascular organs and develop concurrently; therefore, shared pathways almost certainly direct the development of both. The involvement of placental abnormalities in congenital heart disease, whether causal, commensurate or reactive, is under investigated and given the common developmental window and shared developmental pathways of the heart and placenta and concurrent vasculature development, we propose that further investigation combining clinical data, in vitro, in vivo, and computer modeling is fundamental to our understanding and the potential to develop therapeutics.

Early life environment and social determinants of cardiac health in children with congenital heart disease

Congenital heart disease is a significant cause of infant mortality. Epidemiology and social context play a crucial role in conditioning disease burden and modulating outcomes, while diagnosis and treatment remain resource intensive. This review will address the role of social demographics, environmental exposure, epigenetics and nutrition in the aetiology of congenital heart disease. We then discuss the determinant effect of social factors on the provision and outcomes of care for congenital heart disease and implications for practice. It is our hope that enhanced knowledge of the intersection of social determinants of health and congenital heart disease will facilitate effective preventative strategies at the individual and population levels to optimize heart health outcomes across the life course.

Novel mutation of GATA4 gene in Kurdish population of Iran with nonsyndromic congenital heart septals defects

BACKGROUND

The mutations in GATA4 gene induce inherited atrial and ventricular septation defects, which is the most frequent forms of congenital heart defects (CHDs) constituting about half of all cases.

METHOD

We have performed High resolution melting (HRM) mutation scanning of GATA4 coding exons of nonsyndrome 100 patients as a case group including 39 atrial septal defects (ASD), 57 ventricular septal defects (VSD) and four patients with both above defects and 50 healthy individuals as a control group. Our samples are categorized according to their HRM graph. The genome sequencing has been done for 15 control samples and 25 samples of patients whose HRM analysis were similar to healthy subjects for each exon. The PolyPhen-2 and MUpro have been used to determine the causative possibility and structural stability prediction of GATA4 sequence variation.

RESULTS

The HRM curve analysis exhibit that 21 patients and 3 normal samples have deviated curves for GATA4 coding exons. Sequencing analysis has revealed 12 nonsynonymous mutations while all of them resulted in stability structure of protein 10 of them are pathogenic and 2 of them are benign. Also we found two nucleotide deletions which one of them was novel and one new indel mutation resulting in frame shift mutation, and 4 synonymous variations or polymorphism in 6 of patients and 3 of normal individuals. Six or about 50% of these nonsynonymous mutations have not been previously reported.

CONCLUSION

Our results show that there is a spectrum of GATA4 mutations resulting in septal defects.

Positive correlation between pesticide sales and central nervous system and cardiovascular congenital abnormalities in Brazil

BACKGROUND

This study investigated the association between pesticide exposure in Brazil (2005-2013) with rates of central nervous system (CNS) and cardiovascular system (CVS) congenital abnormalities in 2014.

METHOD

An exposure variable was established from data on production and sales of pesticides (kg) per crop area (ha) for 2012 and 2013 years. The Brazilian states were divided into three categories: high, medium, and low pesticide use and rate ratios were estimated for each group of states (CI: 95 %).

RESULTS

In 2013 and 2014, the high use group presented a 100 and a 75 % increase, and the medium group a 65 and 23 % increase, respectively, in the risk of CNS and CVS congenital abnormalities at birth, compared to the low use group.

CONCLUSION

These findings suggest that pesticide exposure could be associated with increased risk of congenital malformations at birth in Brazil.

Valproic acid increases NF-κB transcriptional activation despite decreasing DNA binding ability in P19 cells, which may play a role in VPA-initiated teratogenesis

The nuclear factor-kappa B (NF-κB) family of transcription factors regulate gene expression in response to diverse stimuli. We previously demonstrated that valproic acid (VPA) exposure in utero decreases total cellular protein expression of the NF-κB subunit p65 in CD-1 mouse embryos with a neural tube defect but not in phenotypically normal littermates. This study evaluated p65 mRNA and protein expression in P19 cells and determined the impact on DNA binding ability and activity. Exposure to 5mM VPA decreased p65 mRNA and total cellular protein expression however, nuclear p65 protein expression was unchanged. VPA reduced NF-κB DNA binding and nuclear protein of the p65 DNA-binding partner, p50. NF-κB transcriptional activity was increased with VPA alone, despite decreased phosphorylation of p65 at Ser276, and when combined with tissue necrosis factor α. These results demonstrate that VPA increases NF-κB transcriptional activity despite decreasing DNA binding, which may play a role in VPA-initiated teratogenesis.

Cyanotic congenital heart diseases among Nigerian children

BACKGROUND

There are only few reports on cyanotic congenital heart diseases (CCHD) among Nigerian and African Children. The current report aim to provide the most recent hospital based data on the distribution of CCHD in children less than 14 years of age, the demographic characteristics and risk factors identified.

METHODS

Prospective and cross-sectional involving consecutive cases of CCHD diagnosed with echocardiography at the Lagos State University Teaching Hospital between January 2007 and June 2016. Data were analyzed using Statistical Package for Social Sciences (SPSS) version 20. Level of significance set at P<0.05.

RESULTS

There were 352 subjects with CCHD with a male to female ratio of 1.34:1. The children were age 2 days to 14 years with a mean ± SD of 38.62±44.74 months and median of 21 months. The most common type of CCHD (both isolated and multiple CCHD) was tetralogy of Fallot (TOF) followed double outlet right ventricle (DORV) and transposition of the great arteries (TGA). The most common mode of presentation was cyanosis.

CONCLUSIONS

TOF was found in almost half of the subjects. Cases of DORV which have been rarely reported were more than those with TGA. Most were diagnosed late. Cyanosis was the most common mode of presentation. Clinical features are protean; thus a high index of suspicion is required to make an early diagnosis.

Dieldrin Augments mTOR Signaling and Regulates Genes Associated with Cardiovascular Disease in the Adult Zebrafish Heart (Danio rerio)

Dieldrin is a legacy organochlorine pesticide that is persistent in the environment, despite being discontinued from use in North America since the 1970s. Some epidemiologic studies suggest that exposure to dieldrin is associated with increased risks of neurodegenerative disease and breast cancer by inducing inflammatory responses in tissues as well as oxidative stress. However, the direct effects of organochlorine pesticides on the heart have not been adequately addressed to date given that these chemicals are detectable in human serum and are environmentally persistent; thus, individuals may show latent adverse effects in the cardiovascular system due to long-term, low-dose exposure over time. Our objective was to determine whether low-level exposure to dieldrin at an environmentally relevant dose results in aberrant molecular signaling in the vertebrate heart. Using transcriptomic profiling and immunoblotting, we determined the global gene and targeted protein expression response to dieldrin treatment and show that dieldrin affects gene networks in the heart that are associated with processes related to cardiovascular disease, specifically cardiac arrest and ventricular fibrillation. We report that genes regulating inflammatory responses, a significant risk factor for cardiovascular disease, are upregulated by dieldrin whereas transcripts related to lysosomal function are significantly downregulated. To verify these findings, proteins in these pathways were examined with immunoblotting, and our results demonstrate that dieldrin constitutively activates Akt/mTOR signaling and downregulates lysosomal genes, participating in autophagy. Our data demonstrate that dieldrin induces genes associated with cardiovascular dysfunction and compromised lysosomal physiology, thereby identifying a novel mechanism for pesticide-induced cardiotoxicity.

Effects of Prenatal PM10 Exposure on Fetal Cardiovascular Malformations in Fuzhou, China: A Retrospective Case-Control Study

BACKGROUND

Maternal exposure to ambient air pollution has been associated with an increased risk of congenital heart defects in offspring; however, the results are inconsistent.

OBJECTIVES

We investigated whether there is an association between prenatal exposure to particulate matter with diameter ≤10μm (PM₁₀) during early pregnancy and fetal cardiovascular malformations.

METHODS

The gravidae from a hospital-based case–control study in Fuzhou, China, during 2007–2013 were assigned 10-d or 1-mo averages of daily PM₁₀ using an air monitor–based inverse distance weighting method during early pregnancy. A total of 662 live-birth or selectively terminated cases and 3,972 live-birth controls were enrolled. The exposure was considered as a categorical variable. A multivariable logistic regression model was constructed to quantify the adjusted odds ratios (aORs) of the exposure to PM₁₀ and the risks of fetal cardiovascular malformations.

RESULTS

PM₁₀ levels were positively associated with the risks of atrial septal defect (aORs ranging from 1.29 to 2.17), patent ductus arteriosus [aORs = 1.54, 1.63; 95% confidence intervals (CIs): 1.17, 2.23; 1.06, 3.24], overall fetal cardiovascular malformations (aOR = 1.28; 95% CI: 1.03, 1.61), ventricular septal defect (aOR = 1.19; 95% CI: 1.00, 1.43), and tetralogy of Fallot (aOR = 1.44; 95% CI: 1.01, 2.19) in the various observed periods scaled by 10 d or 1 mo in the first and second gestation months. The strongest associations were observed for exposure to PM₁₀ in the second quartile, whereas the associations were attenuated when higher concentrations of PM₁₀ in the third and fourth quartiles of the exposure were evaluated. No correlations of PM₁₀ levels with these cardiovascular malformations in the other time periods of gestation were observed.

CONCLUSIONS

Our findings suggest some positive associations between maternal exposure to ambient PM₁₀ during the first two months of pregnancy and fetal cardiovascular malformations. https://doi.org/10.1289/EHP289.

Changes in the diagnosis of congenital cardiovascular malformations during the 1st year of life: impacts on epidemiological risk factor associations

Many epidemiological studies base their classification of congenital cardiovascular malformations in newborns upon a single, initial diagnosis. This study aimed to evaluate the effect of subsequent diagnostic investigations on the results of epidemiological studies. We used diagnostic codes from the Baltimore-Washington Infant Study from the time of birth and at ~1 year of age. Odds ratios and 95% confidence intervals were used to identify associations between changes in diagnoses and infant characteristics, time period, that is, before and after introduction of color flow Doppler imaging, and diagnostic variables. Of the 3054 patients with data at both time points, 400 (13.1%) had diagnostic changes. For congenital cardiovascular malformations of early cardiogenesis, such as laterality and looping defects, conotruncal malformations, and atrioventricular septal defects, significant associations were observed between diagnostic change and case infants large for gestational age (odds ratio=0.22, p=0.01), diagnosed initially by echocardiography only (odds ratio=2.05, p=0.001), or with non-cardiac malformations (odds ratio=0.60, p=0.03). For all other congenital cardiovascular malformations, significant associations were observed with echocardiography-only diagnosis (odds ratio=1.43, p=0.04) and non-cardiac malformations (odds ratio=0.57, p<0.001). We found no statistically significant differences between risk factor odds ratios calculated using initial diagnoses versus those calculated using 1-year update diagnoses. Changes in congenital cardiovascular malformation diagnoses from birth to year 1 interval were significantly associated with infant characteristics and diagnostic modality but did not materially affect the outcome of risk factor associations.

An artificial neural network prediction model of congenital heart disease based on risk factors: A hospital-based case-control study

An artificial neural network (ANN) model was developed to predict the risks of congenital heart disease (CHD) in pregnant women.This hospital-based case-control study involved 119 CHD cases and 239 controls all recruited from birth defect surveillance hospitals in Hunan Province between July 2013 and June 2014. All subjects were interviewed face-to-face to fill in a questionnaire that covered 36 CHD-related variables. The 358 subjects were randomly divided into a training set and a testing set at the ratio of 85:15. The training set was used to identify the significant predictors of CHD by univariate logistic regression analyses and develop a standard feed-forward back-propagation neural network (BPNN) model for the prediction of CHD. The testing set was used to test and evaluate the performance of the ANN model. Univariate logistic regression analyses were performed on SPSS 18.0. The ANN models were developed on Matlab 7.1.The univariate logistic regression identified 15 predictors that were significantly associated with CHD, including education level (odds ratio  = 0.55), gravidity (1.95), parity (2.01), history of abnormal reproduction (2.49), family history of CHD (5.23), maternal chronic disease (4.19), maternal upper respiratory tract infection (2.08), environmental pollution around maternal dwelling place (3.63), maternal exposure to occupational hazards (3.53), maternal mental stress (2.48), paternal chronic disease (4.87), paternal exposure to occupational hazards (2.51), intake of vegetable/fruit (0.45), intake of fish/shrimp/meat/egg (0.59), and intake of milk/soymilk (0.55). After many trials, we selected a 3-layer BPNN model with 15, 12, and 1 neuron in the input, hidden, and output layers, respectively, as the best prediction model. The prediction model has accuracies of 0.91 and 0.86 on the training and testing sets, respectively. The sensitivity, specificity, and Yuden Index on the testing set (training set) are 0.78 (0.83), 0.90 (0.95), and 0.68 (0.78), respectively. The areas under the receiver operating curve on the testing and training sets are 0.87 and 0.97, respectively.This study suggests that the BPNN model could be used to predict the risk of CHD in individuals. This model should be further improved by large-sample-size research.

Geographic distribution of live births with tetralogy of Fallot in North Carolina 2003 to 2012

BACKGROUND

Geographic variation in congenital heart disease is not well-described. This study uses geographic information systems (GIS) to describe the spatial epidemiology of tetralogy of Fallot (TOF), in North Carolina (NC) and to compare travel time for cases to congenital heart centers in NC.

METHODS

Using the NC Birth Defects Monitoring Program database, live births with TOF born between 2003 and 2012 were identified. Birth certificates provided demographic variables. A denominator of live births/zip code was obtained from the NC live births database. ArcGIS® software was used to illustrate TOF prevalence by zip code, and SatScanTM was used to identify spatial clusters of TOF cases and to identify changes in cluster location over time. Driving time to each of five NC congenital heart centers was predicted based on road systems information.

RESULTS

A total of 496 infants were born with TOF between 2003 and 2012. The prevalence was 4.2/10,000 live births. A large cluster (330 zip codes, 306 cases) was identified in northeastern NC. Average driving time for each case to closest congenital heart center was: University of North Carolina 37 min, Vident Medical Center 64 min, Duke University 58 min, Carolina's Medical Center 89 min, and Wake Forest Baptist Health 57 min. Overall, average predicted driving time to the nearest congenital heart center was 61 min.

CONCLUSION

Approximately 50 infants/year were born with TOF in NC. One cluster was identified. Further study is necessary to explore potential explanations for the observed case cluster. As interest in regionalization of congenital heart surgery grows, GIS and spatial analysis can become increasingly useful tools for health care planning. Birth Defects Research (Part A) 106:881-887, 2016. © 2016 Wiley Periodicals, Inc.

Neighbourhood Deprivation, Individual-Level and Familial-Level Socio-demographic Factors and Risk of Congenital Heart Disease: A Nationwide Study from Sweden

OBJECTIVES

The purpose of the study is to examine whether there is an association between neighbourhood deprivation and incidence of congenital heart disease (CHD), after accounting for family- and individual-level potential confounders.

METHODS

All children aged 0 to 11 years and living in Sweden (n = 748,951) were followed between January 1, 2000 and December 31, 2010. Data were analysed by multilevel logistic regression, with family- and individual-level characteristics at the first level and level of neighbourhood deprivation at the second level.

RESULTS

During the study period, among a total of 748,951 children, 1499 (0.2%) were hospitalised with CHD. Age-adjusted cumulative hospitalisation rates for CHD increased with increasing level of neighbourhood deprivation. In the study population, 1.8 per 1000 and 2.2 per 1000 children in the least and most deprived neighbourhoods, respectively, were hospitalised with CHD. The incidence of hospitalisation for CHD increased with increasing neighbourhood-level deprivation across all family and individual-level socio-demographic categories. The odds ratio (OR) for hospitalisation for CHD for those living in high-deprivation neighbourhoods versus those living in low-deprivation neighbourhoods was 1.23 (95% confidence interval (CI) = 1.04-1.46). In the full model, which took account for age, paternal and maternal individual-level socio-economic characteristics, comorbidities (e.g. maternal type 2 diabetes, OR = 3.03; maternal hypertension, OR = 2.01), and family history of CHD (OR = 3.27), the odds of CHD were slightly attenuated but did not remain significant in the most deprived neighbourhoods (OR = 1.20, 95% CI = 0.99-1.45, p = 0.057).

CONCLUSIONS

This study is the largest so far on neighbourhood influences on CHD, and the results suggest that deprived neighbourhoods have higher rates of CHD, which represents important clinical knowledge. However, the association does not seem to be independent of individual- and family-level characteristics.

The Increasing Prevalence in Intersex Variation from Toxicological Dysregulation in Fetal Reproductive Tissue Differentiation and Development by Endocrine-Disrupting Chemicals

An increasing number of children are born with intersex variation (IV; ambiguous genitalia/hermaphrodite, pseudohermaphroditism, etc.). Evidence shows that endocrine-disrupting chemicals (EDCs) in the environment can cause reproductive variation through dysregulation of normal reproductive tissue differentiation, growth, and maturation if the fetus is exposed to EDCs during critical developmental times in utero. Animal studies support fish and reptile embryos exhibited IV and sex reversal when exposed to EDCs. Occupational studies verified higher prevalence of offspring with IV in chemically exposed workers (male and female). Chemicals associated with endocrine-disrupting ability in humans include organochlorine pesticides, poly-chlorinated biphenyls, bisphenol A, phthalates, dioxins, and furans. Intersex individuals may have concurrent physical disorders requiring lifelong medical intervention and experience gender dysphoria. An urgent need exists to determine which chemicals possess the greatest risk for IV and the mechanisms by which these chemicals are capable of interfering with normal physiological development in children.

Risk factors of different congenital heart defects in Guangdong, China

BACKGROUND

Limited studies have evaluated the risk factors for congenital heart defects (CHDs) in China and compared them for different types of CHDs. This study examined risk factors between isolated and multiple CHDs as well as among CHDs subtypes in Guangdong, Southern China.

METHODS

This population-based case-control study included 4,034 pairs of case and control infants enrolled in the Guangdong Registry of CHD study, 2004-2013. Multivariate logistic regression was used to compute adjusted odds ratios (ORs) while simultaneously controlling for confounders.

RESULTS

Multiple maternal environmental exposures, including living in newly renovated rooms, residential proximity to main traffic, paternal smoking, and maternal occupation as manual worker, were significantly associated with CHDs with ORs ranging 1.30-9.43. Maternal perinatal diseases (including maternal fever, diabetes, influenza, and threatened abortion), maternal medication use (antibiotic use), advanced maternal age, low socioeconomic status, and paternal alcohol intake were also significantly associated with CHDs, with ORs ranging 1.60-3.96. Isolated CHDs and multiple defects have different profiles of risk factors, while subtype of CHD shares common risk factors.

CONCLUSION

These results suggest that maternal environmental exposures/occupation and perinatal diseases/medication use were dominant risk factors associated with CHDs in Southern China. Isolated and multiple CHDs may have different etiologic factors.

Association Between Sequence Variations in RCAN1 Promoter and the Risk of Sporadic Congenital Heart Disease in a Chinese Population

The pathogenesis of congenital heart disease (CHD) is unclear. There is a high incidence of CHD in Down syndrome, in which RCAN1 (regulator of calcineurin 1) overexpression is observed. However, whether RCAN1 plays an important role in non-syndromic CHD is unknown. This study investigates the relationship between sequence variations in the RCAN1 promoter and sporadic CHD. This was a case-control study in which the RCAN1 promoter was cloned and sequenced in 128 CHD patients (median age 1.1 year) and 150 normal controls (median age 3.0 year). No mutation sites had been identified in this research. Three single-nucleotide (C to T) polymorphisms were detected: rs193289374, rs149048873 and rs143081213. The polymorphisms were not associated with CHD risk according to a logistic regression analysis. Functional assays in vitro showed that compared with the wild-type genotype, the rs149048873 polymorphism decreased, and the rs143081213 increased, the RCAN1 promoter activity, though the rs193289374 polymorphism had no effect. In conclusion, the sequence variations in RCAN1 promoter are not major genetic factors involved in sporadic CHD, at least in the current research population.

A Novel TBX1 Loss-of-Function Mutation Associated with Congenital Heart Disease

Congenital heart disease (CHD) is the most prevalent type of birth defect in humans and is the leading non-infectious cause of infant death worldwide. There is a growing body of evidence demonstrating that genetic defects play an important role in the pathogenesis of CHD. However, CHD is a genetically heterogeneous disease and the genetic basis underpinning CHD in an overwhelming majority of patients remains unclear. In this study, the coding exons and splice junction sites of the TBX1 gene, which encodes a T-box homeodomain transcription factor essential for proper cardiovascular morphogenesis, were sequenced in 230 unrelated children with CHD. The available family members of the index patient carrying an identified mutation and 200 unrelated ethnically matched healthy individuals used as controls were subsequently genotyped for TBX1. The functional effect of the TBX1 mutation was predicted by online program MutationTaster and characterized by using a dual-luciferase reporter assay system. As a result, a novel heterozygous TBX1 mutation, p.Q277X, was identified in an index patient with double outlet right ventricle (DORV) and ventricular septal defect (VSD). Genetic analysis of the proband's available relatives showed that the mutation co-segregated with CHD transmitted in an autosomal dominant pattern with complete penetrance. The nonsense mutation, which was absent in 400 control chromosomes, altered the amino acid that was completely conserved evolutionarily across species and was predicted to be disease-causing by MutationTaster. Biochemical analysis revealed that Q277X-mutant TBX1 lost transcriptional activating function when compared with its wild-type counterpart. This study firstly associates TBX1 loss-of-function mutation with enhanced susceptibility to DORV and VSD in humans, which provides novel insight into the molecular mechanism underlying CHD and suggests potential implications for the development of new preventive and therapeutic strategies for CHD.

Secondary Particulate Matter Originating from an Industrial Source and Its Impact on Population Health

Epidemiological studies have reported adverse associations between long-term exposure to ambient particulate matter (PM_2.5) and several health outcomes. One issue in this field is exposure assessment and, in particular, the role of secondary PM_2.5, often neglected in environmental and health risk assessment. Thus, the aim of this work was to evaluate the long-term environmental and health impact of primary and secondary PM_2.5 concentrations originating from a single industrial source. As a case study, we considered a coal power plant which is a large emitter of both primary PM_2.5 and secondary PM_2.5 precursors. PM_2.5 concentrations were estimated using the Calpuff dispersion model. The health impact was expressed in terms of number of non-accidental deaths potentially attributable to the power plant. Results showed that the estimated secondary PM_2.5 extended over a larger area than that related to primary PM_2.5 with maximum concentration values of the two components well separated in space. Exposure to secondary PM_2.5 increased significantly the estimated number of annual attributable non-accidental deaths. Our study indicates that the impact of secondary PM_2.5 may be relevant also at local scale and ought to be considered when estimating the impact of industrial emissions on population health.

A novel NKX2.6 mutation associated with congenital ventricular septal defect

Congenital heart disease (CHD) is the most common birth defect and is the most prevalent non-infectious cause of infant death. Aggregating evidence demonstrates that genetic defects are involved in the pathogenesis of CHD. However, CHD is genetically heterogeneous and the genetic determinants for CHD in an overwhelming majority of patients remain unknown. In this study, the coding regions and splice junctions of the NKX2.6 gene, which encodes a homeodomain transcription factor crucial for cardiovascular development, were sequenced in 210 unrelated CHD patients. As a result, a novel heterozygous NKX2.6 mutation, p.K152Q, was identified in an index patient with ventricular septal defect (VSD). Genetic analysis of the proband's available family members showed that the mutation cosegregated with VSD transmitted as an autosomal dominant trait with complete penetrance. The missense mutation was absent in 400 control chromosomes and the altered amino acid was completely conserved evolutionarily across species. Due to unknown transcriptional targets of NKX2.6, the functional characteristics of the identified mutation at transcriptional activity were analyzed by using NKX2.5 as a surrogate. Alignment between human NKX2.6 and NKX2.5 proteins displayed that K152Q-mutant NKX2.6 was equivalent to K158Q-mutant NKX2.5, and introduction of K158Q into NKX2.5 significantly reduced its transcriptional activating function when compared with its wild-type counterpart. This study firstly links NKX2.6 loss-of-function mutation with increased susceptibility to isolated VSD, providing novel insight into the molecular mechanism underpinning VSD and contributing to the development of new preventive and therapeutic strategies for this common form of CHD.