Congenital heart disease in infants of diabetic mothers: echocardiographic study

Maternal poor glycemic control increases risk of neonatal left ventricular hypertrophy

BACKGROUND

Left ventricular hypertrophy (LVH) is an important complication of infants of diabetic mothers (IDMs). However, the defined factors, such as the influence of glycemic control, insulin administration of diabetic mothers and large for gestational age (LGA) in infants, are largely unknown on the incidence of LVH. Therefore, this study aimed to evaluate the prevalence of maternal and neonatal risk factors associated with LVH in IDMs.

METHODS

This prospective analytic study was conducted at tertiary care hospitals in a 1-year period. Inborn IDMs were enrolled, and ventricular hypertrophy was identified by 2D echocardiography in the first 72 hours after birth.

RESULTS

A total of 160 IDMs met the inclusion criteria, 33 (20.6%) of which had LVH. The incidence of infants with LVH born to mothers with poor glycemic control (fasting blood sugar >95 mg/dL) was significantly elevated than those with good glycemic control (45.5% vs. 14.4%, P<0.001). Twelve IDMs (12/33, 36.5%) of LVH and 17 IDMs (17/127, 13.4%) of non-LVH were LGA. IDMs with LVH, compared those with non-LVH, had significantly increased left ventricular (LV) geometry; IVSd (6.5±0.8 vs. 4.0±0, 7 mm), LV IDd (16.8±3.3 mm vs. 18.4±1.1), left ventricular ejection fraction (LVEF) (68.3±8.5% vs. 62.9±17.5%), left ventricular fraction shortening (LVFS) (35.9±6.6% vs. 32.2±5.5%), LV mass (15.3±11.6 vs. 9.3±2.5 g) and LV mass index (66.2±17.5 vs. 46.6±9.7 g/m2), all with P<0.001. There was significant correlation in LV mass with infants' weight, height and body surface area (BSA) (r=0.408, 0.337 and 0.424, respectively; P<0.001).

CONCLUSIONS

The prevalence of neonatal ventricular hypertrophy in IDMs was 20.6%. Maternal poor glycemic control and LGA status in IDMs were dominant risk factors of LVH.

Disease features and management of cardiomyopathies in women

Over the last years, there has been a growing interest in the clinical manifestations and outcomes of cardiomyopathies in women. Peripartum cardiomyopathy is the only women-specific cardiomyopathy. In cardiomyopathies with X-linked transmission, women are not simply healthy carriers of the disorder, but can show a wide spectrum of clinical manifestations ranging from mild to severe manifestations because of heterogeneous patterns of X-chromosome inactivation. In mitochondrial disorders with a matrilinear transmission, cardiomyopathy is part of a systemic disorder affecting both men and women. Even some inherited cardiomyopathies with autosomal transmission display phenotypic and prognostic differences between men and women. Notably, female hormones seem to exert a protective role in hypertrophic cardiomyopathy (HCM) and variant transthyretin amyloidosis until the menopausal period. Women with cardiomyopathies holding high-risk features should be referred to a third-level center and evaluated on an individual basis. Cardiomyopathies can have a detrimental impact on pregnancy and childbirth because of the associated hemodynamic derangements. Genetic counselling and a tailored cardiological evaluation are essential to evaluate the likelihood of transmitting the disease to the children and the possibility of a prenatal or early post-natal diagnosis, as well as to estimate the risk associated with pregnancy and delivery, and the optimal management strategies.

Maternal Diabetes and Intrapartum Fetal Electrocardiogram

OBJECTIVE

 Fetal electrocardiogram (ECG) ST changes are associated with fetal cardiac hypoxia. Our objective was to evaluate ST changes by maternal diabetic status and stage of labor.

METHODS

 This was a secondary analysis of a multicentered randomized-controlled trial in which laboring patients with singleton gestations underwent fetal ECG scalp electrode placement and were randomly assigned to masked or unmasked ST-segment readings. Our primary outcome was the frequency of fetal ECG tracings with ST changes by the stage of labor. ECG tracings were categorized into mutually exclusive groups (ST depression, ST elevation without ST depression, or no ST changes). We compared participants with DM, gestational diabetes mellitus (GDM), and no DM.

RESULTS

 Of the 5,436 eligible individuals in the first stage of labor (95 with pregestational DM and 370 with GDM), 4,427 progressed to the second stage. ST depression occurred more frequently in the first stage of labor in participants with pregestational DM (15%, adjusted odds ratio [aOR] 2.20, 95% confidence interval [CI] 1.14-4.24) and with GDM (9.5%, aOR 1.51, 95% CI 1.02-2.25) as compared with participants without DM (5.7%). The frequency of ST elevation was similar in participants with pregestational DM (33%, aOR 0.79, 95% CI 0.48-1.30) and GDM (33.2%, aOR 0.91, 95% CI 0.71-1.17) as compared with those without DM (34.2%). In the second stage, ST depression did not occur in participants with pregestational DM (0%) and occurred more frequently in participants with GDM (3.5%, aOR 2.01, 95% CI 1.02-3.98) as compared with those without DM (2.0%). ST elevation occurred more frequently in participants with pregestational DM (30%, aOR 1.81, 95% CI 1.02-3.22) but not with GDM (19.0%, aOR 1.06, 95% CI 0.77-1.47) as compared with those without DM (17.8%).

CONCLUSION

 ST changes in fetal ECG occur more frequently in fetuses of diabetic mothers during labor.

CLINICALTRIALS

gov number, NCT01131260.

PRECIS

 ST changes in fetal ECG, a marker of fetal cardiac hypoxia, occur more frequently in fetuses of diabetic parturients.

KEY POINTS

· Fetal hypertrophic cardiomyopathy (HCM) and cardiac dysfunction occur frequently among fetuses of diabetic patients.. · Fetal ECG changes such as ST elevation and depression reflect cardiac hypoxia.. · Fetuses of diabetic patients demonstrate a higher prevalence of fetal ECG tracings with ST changes..

Outcome monitoring and risk stratification after cardiac procedure in neonates, infants, children and young adults born with congenital heart disease: protocol for a multicentre prospective cohort study (Children OMACp)

INTRODUCTION

Congenital heart disease (CHD) represents the most common birth defect, affecting from 0.4% to 1.2% of children born in developed countries. The survival of these patients has increased significantly, but CHD remains one of the major causes of neonatal and childhood death. The aetiology of CHD is complex, with some evidence of both genetic and environmental causes. However, there is still lack of knowledge regarding modifiable risk factors and molecular and genetic mechanisms underlying the development of CHD. This study aims to develop a prospective cohort of patients undergoing cardiac procedures that will bring together routinely collected clinical data and biological samples from patients and their biological mothers, in order to investigate risk factors and predictors of postoperative-outcomes, as well as better understanding the effect of the surgical intervention on the early and long-term outcomes.

METHODS AND ANALYSIS

Children OMACp (OMACp, outcome monitoring after cardiac procedure in congenital heart disease) is a multicentre, prospective cohort study recruiting children with CHD undergoing a cardiac procedure. The study aims to recruit 3000 participants over 5 years (2019-2024) across multiple UK sites. Routine clinical data will be collected, as well as participant questionnaires collecting sociodemographic, NHS resource use and quality of life data. Biological samples (blood, urine and surgical waste tissue from patients, and blood and urine samples from biological mothers) will be collected where consent has been obtained. Follow-up outcome and questionnaire data will be collected for 5 years.

ETHICS AND DISSEMINATION

The study was approved by the London-Brent Research Ethics Committee on 30 July 2019 (19/SW/0113). Participants (or their parent/guardian if under 16 years of age) must provide informed consent prior to being recruited into the study. Mothers who wish to take part must also provide informed consent prior to being recruited. The study is sponsored by University Hospitals Bristol and Weston Foundation Trust and is managed by the University of Bristol. Children OMACp is adopted onto the National Institute for Health Research Clinical Research Network portfolio. Findings will be disseminated through peer-reviewed publications, presentation at conference, meetings and through patient organisations and newsletters.

TRIAL REGISTRATION NUMBER

ISRCTN17650644.

Cardiac hypertrophy and insulin therapy in a pre-term newborn: is there a relationship?

Background

Hypertrophic cardiomyopathy (HCM) in newborns is a rare condition with heterogeneous etiologies. While the relationship between hyperinsulinism and cardiac hypertrophy (CH) is known, hyperinsulinism has not been reported as cause of HCM.

Case presentation

We report the case of cardiac hypertrophy (CH) in an Extremely Low Birth Weight (ELBW) infant; this patient underwent insulin therapy after the onset of persistent hyperglycemia due to parenteral nutrition (PN), supporting the hypothesis of a role of iatrogenic hyperinsulinemia in the development of HCM.

Conclusions

The present case underlines the importance of a close cardiological follow-up in infants undergoing insulin infusion for an alteration in the glucose metabolism.

Impact of maternal hyperglycemia on cardiac development: Insights from animal models

Congenital heart disease (CHD) is the leading cause of birth defect-related death in infants and is a global pediatric health concern. While the genetic causes of CHD have become increasingly recognized with advances in genome sequencing technologies, the etiology for the majority of cases of CHD is unknown. The maternal environment during embryogenesis has a profound impact on cardiac development, and numerous environmental factors are associated with an elevated risk of CHD. Maternal diabetes mellitus (matDM) is associated with up to a fivefold increased risk of having an infant with CHD. The rising prevalence of diabetes mellitus has led to a growing interest in the use of experimental diabetic models to elucidate mechanisms underlying this associated risk for CHD. The purpose of this review is to provide a comprehensive summary of rodent models that are being used to investigate alterations in cardiac developmental pathways when exposed to a maternal diabetic setting and to summarize the key findings from these models. The majority of studies in the field have utilized the chemically induced model of matDM, but recent advances have also been made using diet based and genetic models. Each model provides an opportunity to investigate unique aspects of matDM and is invaluable for a comprehensive understanding of the molecular and cellular mechanisms underlying matDM-associated CHD.

Effect of maternal diabetes on fetal heart function on echocardiography: systematic review and meta-analysis

OBJECTIVE

Maternal diabetes in pregnancy is associated with structural anomalies of the fetal heart, as well as hypertrophy and functional impairment. This systematic review and meta-analysis aimed to estimate the effect of maternal diabetes on fetal cardiac function as measured by prenatal echocardiography.

METHODS

We performed a search of the EMBASE, PubMed and The Cochrane Library databases, from inception to 4 July 2019, for studies evaluating fetal cardiac function using echocardiography in pregnancies affected by diabetes compared with uncomplicated pregnancies. Outcome measures were cardiac hypertrophy and diastolic, systolic and overall cardiac function as assessed by various ultrasound parameters. The quality of the studies was assessed using the Newcastle-Ottawa Scale. Data on interventricular septal (IVS) thickness, myocardial performance index (MPI) and E/A ratio were pooled for the meta-analysis using random-effects models. For pregnancies with diabetes, results were reported overall and according to whether diabetes was pregestational (PDM) or gestational (GDM). Results were also stratified according to the trimester in which fetal cardiac assessment was performed.

RESULTS

Thirty-nine studies were included, comprising data for 2276 controls and 1925 women with pregnancy affected by diabetes mellitus (DM). Of these, 1120 had GDM, 671 had PDM and in 134 cases diabetes type was not specified. Fetal cardiac hypertrophy was more prevalent in diabetic pregnancies than in non-diabetic controls in 21/26 studies, and impaired diastolic function was observed in diabetic pregnancies in 22/28 studies. The association between DM and systolic function was inconsistent, with 10/25 studies reporting no difference between cases and controls, although more recent studies measuring cardiac deformation, i.e. strain, did show decreased systolic function in diabetic pregnancies. Of the studies measuring overall fetal cardiac function, the majority (14/21) found significant impairment in diabetic pregnancies. Results were similar when stratified according to GDM or PDM. These effects were already present in the first trimester, but were most profound in the third trimester. Meta-analysis of studies performed in the third trimester showed, compared with controls, increased IVS thickness in both PDM (mean difference, 0.75 mm (95% CI, 0.56-0.94 mm)) and GDM (mean difference, 0.65 mm (95% CI, 0.39-0.91 mm)) pregnancies, decreased E/A ratio in PDM pregnancies (mean difference, -0.09 (95% CI, -0.15 to -0.03)), no difference in E/A ratio in GDM pregnancies (mean difference, -0.01 (95% CI, -0.02 to 0.01)) and no difference in MPI in either PDM (mean difference, 0.04 (95% CI, -0.01 to 0.09)) or GDM (mean difference, 0.03 (95% CI, -0.01 to 0.06)) pregnancies.

CONCLUSIONS

The findings of this review show that maternal diabetes is associated with fetal cardiac hypertrophy, diastolic dysfunction and overall impaired myocardial performance on prenatal ultrasound, irrespective of whether diabetes is pregestational or gestational. Further studies are needed to demonstrate the relationship with long-term outcomes. © 2020 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

The Incidence of Congenital Heart Defects in Offspring Among Women With Diabetes in Saudi Arabia

BACKGROUND

The risk of congenital anomalies is increased in infants of diabetic mothers (IDM). The most frequent cardiac anomalies in IDMs include ventricular septal defect, transposition of great arteries, and aortic stenosis.

OBJECTIVE

Estimating the incidence of infants with congenital heart defects (CHD) whose mothers have diabetes in Saudi Arabia at a tertiary hospital in the National Guard Health Affairs (NGHA) system.

MATERIALS AND METHODS

This study was a retrospective cohort. The population was all births of type 1 and type 2 diabetic mothers and non-diabetic mothers (also mothers with gestational diabetes) in NGHA by following the exclusion criteria, which were mothers over 40 and below 20 years of age, and other risk factors such as drug-induced congenital disease. The data was from deliveries from January 1st 2018 to January 1st 2019. Data were collected by chart review using the Best-Care system at NGHA hospital. Statistical Package for the Social Sciences (SPSS) version 20 (IBM Corp., Armonk, NY, USA) was used for the statistical analysis.

RESULTS

A total of 1838 diabetic mothers and non-exposure, non-diabetic mothers, with the outcome of whether the infant had CHD, were included in this study. Most of the mothers (544, 30.11%) were aged 30-34 years old. About two-thirds of mothers, 1161 (63.24%), weren't diabetic, 500 (27.23%) had gestational diabetes, 132 (7.19%) were type 2 diabetes (T2DM), and 43 (2.34%) were type 1 diabetes (T1DM). Two hundred eighteen (11.82%) offspring had CHD, and the remaining 1625 (88.17%) did not. The most frequent echocardiographic abnormalities in infants of diabetic mothers were patent ductus arteriosus (PDA) (31.75%), patent foramen ovale (PFO) (31.75%), and atrial septal defect (ASD) (23.64%).

CONCLUSION

The incidence of CHD among infants of included mothers in this cohort study was 11.82%. The most frequent echocardiographic abnormalities in the infants of diabetics were PDA and PFO. The incidence of CHD was higher among mothers who had T1DM followed by T2DM, and whose ages were between 30-34.

Effect of Gestational Diabetes Mellitus on Neonatal Myocardial Function

BACKGROUND AND AIMS

Infants born to mothers with gestational diabetes mellitus (GDM) have impaired myocardial performance and are at risk of pulmonary hypertension. We aimed to assess myocardial deformation and left ventricular (LV) rotational mechanics in this population.

METHODS

We studied 40 infants of mothers with GDM and 40 control infants. Three echocardiograms were carried out over the first 3 days after birth.

RESULTS

GDM infants had a lower gestation at birth and a thicker septal wall, a higher LV eccentricity index (indicating septal bowing), and a lower PAATi (indicating higher pulmonary vascular resistance) (all p < 0.05). GDM infants had lower LV strain, systolic and early diastolic strain rates, lower right ventricular (RV) strain, and early diastolic strain rates over the study period (all p < 0.05). By day 3, GDM infants had higher twist, torsion, and higher LV twist and untwist rates (all p < 0.05). GDM status was an independent predictor of LV and RV function and pulmonary vascular resistance (p < 0.01).

CONCLUSION

Infants of mothers with GDM demonstrate important changes in myocardial function in addition to pulmonary vascular resistance that do not resolve by hospital discharge. The observed LV twist increase in GDM infants may be a compensatory mechanism for the lower longitudinal function in this cohort.

Fetal Cardiac Functional Abnormalities Assessed by Echocardiography in Mothers Suffering Gestational Diabetes Mellitus: A Systematic Review and Meta-analysis

Abnormal cardiovascular changes especially hypertrophic cardiomyopathy is potentially expected in the fetuses of the diabetic pregnancy women. However, there is still little consensus on quantitative cardiac abnormalities in infants with diabetic mothers. The present study comprehensively analyzed the studies on functional changes in heart in infants of diabetic mothers with a greater focus on occurrence of hypertrophic cardiomyopathy. All comparative studies evaluating and comparing quantitatively the changes in cardiac parameters using echocardiography in fetuses with and without diabetic mothers were eligible for assessment. The included studies were identified through electronically reviewing the manuscripts databases of MEDLINE, EMBASE, Web of knowledge, and Google Scholar from inception to May 2020. The meta-analysis included 11 comparative with overall 849 fetuses for gestational diabetic mothers and 1247 for healthy mothers. Assessing cardiac diameters by fetal echocardiography showed significantly lower mitral E/A ratio, lower tricuspid E/A ratio, higher interventricular septal thickness, higher myocardial performance index, higher isovolumic relaxation time, and higher isovolumic contraction time in fetuses of gestational diabetes mellitus group as compared to healthy group adjusting for gestational diabetes mellitus. The presence of gestational diabetes mellitus can potentially affect the fetal cardiac parameters especially as hypertrophic cardiomyopathy leading both cardiac systolic and diastolic dysfunction.

Stillbirth in women with diabetes: a retrospective analysis of fetal autopsy reports

Introduction: Diabetes in pregnancy is associated with an increased rate of stillbirth. There are a wide variety of factors that have been implicated including placental insufficiency, hypoxia, hyperinsulinemia and impaired cardiac function. Furthermore, there is evidence that diabetic pregnancies have an increased rate of fetal cardiomyopathy as compared to non-diabetic pregnancies. Prior studies have indicated that this association can also be an etiology for diabetic stillbirth. The purpose of this study was to determine if diabetic pregnancies have an increased risk of fetal cardiomyopathy identified on fetal autopsy as compared to non-diabetic women with a stillbirth in a cohort of pregnancies that had evaluation with a fetal autopsy.Materials and methods: Retrospective cohort study of women with a stillbirth who consented to fetal autopsy at an academic medical center from 2011 to 2017. Stillbirth was defined as an intrauterine fetal demise at ≥20 weeks' gestation. Women with diabetes defined as pre-gestational diabetes type 1, pre-gestational diabetes type 2, and gestational diabetes were compared to women without diabetes. Primary outcome was fetal cardiomyopathy. Other etiologies for stillbirth were also evaluated and classified according to the Stillbirth Collaborative Research Network (SCRN) initial causes of fetal death. Fisher exact test, χ2 test, and Mann Whitney U tests were performed as appropriate, with p < .05 considered significant. Generalized linear models were performed for fetal organ weights controlling for gestational age of delivery, maternal chronic hypertension, delivery body mass index, and birthweight.Results: A total of 78 women elected to have fetal autopsy examinations during the study period. Of these, 75 had complete information available for review. A total of 60 women did not have diabetes and 15 women had diabetes. Of pregnancies complicated by diabetes, 11 had insulin dependent diabetes and 4 had non-insulin dependent diabetes. Fetal cardiomyopathy was diagnosed on autopsy for 7 (46.7%) of pregnancies with diabetes and 2 (3.3% of pregnancies without diabetes (RR 14.00 [95% CI 3.23-60.65], p < .001). These associations were still significant even when analyzing only those pregnancies without fetal congenital heart disease (7 [46.7%] diabetic pregnancies with cardiomyopathy versus 1 [2.0%] nondiabetic pregnancy with cardiomyopathy, RR 23.80 [95% CI 3.17-178.46], p < .001). There was no difference between diabetic and non-diabetic pregnancies in regards to other causes for stillbirth. Stillbirths in pregnancies with diabetes also had larger fetal heart, liver, and adrenal weights on fetal autopsy.Conclusion: Women with diabetes have 14 times the risk of fetal cardiomyopathy identified at fetal autopsy as compared to women without diabetes. As the prediction and prevention of diabetic stillbirth is limited, information on potential causes of stillbirth may help future research identify those pregnancies at the greatest risk for adverse outcome.

Metabolic environment in vivo as a blueprint for differentiation and maturation of human stem cell-derived cardiomyocytes

Patient-derived human pluripotent stem cell-derived cardiomyocytes (hPSC-CMs) are increasingly being used for disease modeling, drug screening and regenerative medicine. However, to date, an immature, fetal-like, phenotype of hPSC-CMs restrains their full potential. Increasing evidence suggests that the metabolic state, particularly important for provision of sufficient energy in highly active contractile CMs and anabolic and regulatory processes, plays an important role in CM maturation, which affects crucial functional aspects of CMs, such as contractility and electrophysiology. During embryonic development the heart is subjected to metabolite concentrations that differ substantially from that of hPSC-derived cardiac cell cultures. A deeper understanding of the environmental and metabolic cues during embryonic heart development and how these change postnatally, will provide a framework for optimizing cell culture conditions and maturation of hPSC-CMs. Maturation of hPSC-CMs will improve the predictability of disease modeling, drug screening and drug safety assessment and broadens their applicability for personalized and regenerative medicine.

Neonatal cardiac hypertrophy: the role of hyperinsulinism-a review of literature

Hypertrophic cardiomyopathy (HCM) in neonates is a rare and heterogeneous disorder which is characterized by hypertrophy of heart with histological and functional disruption of the myocardial structure/composition. The prognosis of HCM depends on the underlying diagnosis. In this review, we emphasize the importance to consider hyperinsulinism in the differential diagnosis of HCM, as hyperinsulinism is widely associated with cardiac hypertrophy (CH) which cannot be distinguished from HCM on echocardiographic examination. We supply an overview of the incidence and treatment strategies of neonatal CH in a broad spectrum of hyperinsulinemic diseases. Reviewing the literature, we found that CH is reported in 13 to 44% of infants of diabetic mothers, in approximately 40% of infants with congenital hyperinsulinism, in 61% of infants with leprechaunism and in 48 to 61% of the patients with congenital generalized lipodystrophy. The correct diagnosis is of importance since there is a large variation in prognoses and there are various strategies to treat CH in hyperinsulinemic diseases.Conclusion: The relationship between CH and hyperinsulism has implications for clinical practice as it might help to establish the correct diagnosis in neonates with cardiac hypertrophy which has both prognostic and therapeutic consequences. In addition, CH should be recognized as a potential comorbidity which might necessitate treatment in all neonates with known hyperinsulinism.What is Known:• Hyperinsulinism is currently not acknowledged as a cause of hypertrophic cardiomyopathy (HCM) in textbooks and recent Pediatric Cardiomyopathy Registry publications.What is New:• This article presents an overview of the literature of hyperinsulinism in neonates and infants showing that hyperinsulinism is associated with cardiac hypertrophy (CH) in a broad range of hyperinsulinemic diseases.• As CH cannot be distinguished from HCM on echocardiographic examination, we emphasize the importance to consider hyperinsulinism in the differential diagnosis of HCM/CH as establishing the correct diagnosis has both prognostic and therapeutic consequences.

Relationship between hemoglobin A1c and serum troponin in patients with diabetes and cardiovascular events

Objectives

Diabetes mellitus is a group of metabolic disorders associated with high risk for cardiovascular disease. Although troponins are primarily clinically used for the diagnosis of acute coronary syndrome, they are also used in risk assessment in patients with acute coronary syndrome as well as in a number of other conditions. The aim of this review was to investigate the relationship between hemoglobin A1c and serum troponin in patients with diabetes and cardiovascular events.

Methods

Hemoglobin A1_c has been chosen as the best clinical indicator of glucose control and risk of micro and macrovascular complications. We investigated cardiac troponins as a group of markers of muscle injury which includes troponin T, troponin I and troponin C. Troponin T and I are specific for myocardial injury, compared to C which is specific for skeletal muscle.

Results

In this review, we showed that there was a causal relation between hemoglobin A1_c levels and serum troponin concentrations. Hemoglobin A1_c has shown to be a positive predictive factor of incidence, mortality and morbidity of conditions such as acute coronary syndrome, arrhythmias, stroke, pulmonary embolism and other conditions that causes troponin elevation by its release in circulation.

Conclusions

Chronic hyperglycemia decreases glomerular filtration and consequently decreases troponin elimination and also by affecting the heart microcirculation it leads to microvascular damage and consequently to ischemia which contribute to troponin concentration elevation. Furthermore, correlation between hemoglobin A1_c and troponin concentration manifests in their prognostic value for mortality.

Say NO to ROS: Their Roles in Embryonic Heart Development and Pathogenesis of Congenital Heart Defects in Maternal Diabetes

Congenital heart defects (CHDs) are the most prevalent and serious birth defect, occurring in 1% of all live births. Pregestational maternal diabetes is a known risk factor for the development of CHDs, elevating the risk in the child by more than four-fold. As the prevalence of diabetes rapidly rises among women of childbearing age, there is a need to investigate the mechanisms and potential preventative strategies for these defects. In experimental animal models of pregestational diabetes induced-CHDs, upwards of 50% of offspring display congenital malformations of the heart, including septal, valvular, and outflow tract defects. Specifically, the imbalance of nitric oxide (NO) and reactive oxygen species (ROS) signaling is a major driver of the development of CHDs in offspring of mice with pregestational diabetes. NO from endothelial nitric oxide synthase (eNOS) is crucial to cardiogenesis, regulating various cellular and molecular processes. In fact, deficiency in eNOS results in CHDs and coronary artery malformation. Embryonic hearts from diabetic dams exhibit eNOS uncoupling and oxidative stress. Maternal treatment with sapropterin, a cofactor of eNOS, and antioxidants such as N-acetylcysteine, vitamin E, and glutathione as well as maternal exercise have been shown to improve eNOS function, reduce oxidative stress, and lower the incidence CHDs in the offspring of mice with pregestational diabetes. This review summarizes recent data on pregestational diabetes-induced CHDs, and offers insights into the important roles of NO and ROS in embryonic heart development and pathogenesis of CHDs in maternal diabetes.

Clinical analysis of prenatal ultrasound diagnosis of fetal cardiovascular malformations in the first and second trimesters of pregnancy: A CARE-compliant article

Fetal cardiovascular malformations is widely focused and screened, but the accuracy of screening is not satisfactory. In this study, we compared the types of congenital heart malformation, accompanying diseases and fetal outcomes in the first and second trimesters of pregnancy to clarify the advantage of early screening.From January 2013 to June 2018, 230 fetuses were diagnosed with congenital heart malformations using ultrasound method in Qilu Hospital of Shandong University, and divided into 2 groups:the first trimester fetuses (group A) and the second trimester fetuses (group B). In addition, we collected and organized medical data of 347 cases diagnosed with congenital heart disease during 1998 to 2005 (group C). We compared the spectrum of congenital heart disease, associated comorbidities and outcome of fetuses diagnosed with congenital heart disease.There were differences in the types and incidence of cardiac malformations between the first and second trimesters of pregnancy. The number of cases of non-cardiac malformation, congenital heart disease with single ventricular circulation, fetal intrauterine death and premature pregnancy termination was significantly lower in the late stage (group A and group B) than that in the early stage (group C). More patients were screened for trisomy 21, 18, 13 syndromes and Turner syndrome in group A than group B (P <.001). More fetuses with a 22q11 deletion were screened in group B than group C.Early pregnancy screening using ultrasound diagnosis is very important for fetuses with congenital heart disease.

Maternal Body Mass Index and Risk of Congenital Heart Defects in Infants: A Dose-Response Meta-Analysis

Objective

The exact shape of the dose-response relationship between maternal body mass index (BMI) and the risk of congenital heart defects (CHDs) in infants has not been clearly defined yet. This study aims to further clarify the relationship between maternal obesity and the risk of CHDs in infants by an overall and dose-response meta-analysis.

Methods

PubMed, Embase, and Web of Science databases were searched to identify all related studies. The studies were limited to human cohort or case-control studies in English language. Random-effect models and dose-response meta-analysis were used to synthesize the results. Heterogeneity, subgroup analysis, sensitivity analysis, and publication bias were also assessed.

Results

Nineteen studies with 2,416,546 participants were included in our meta-analysis. Compared with the mothers with normal weight, the pooled relative risks (RRs) of infants with CHDs were 1.08 (95% CI=1.03-1.13) in overweight and 1.23 (95% CI=1.17-1.29) in obese mothers. According to the findings from the linear meta-analysis, we observed an increased risk of infants with CHDs (RR=1.07, 95% CI=1.06-1.08) for each 5 kg/m² increase in maternal BMI. A nonlinear relationship between maternal BMI and risk of infants with CHDs was also found (p=0.012).

Conclusion

The results from our meta-analysis indicate that increased maternal BMI is related to increased risk of CHDs in infants.

Diabetic Pregnancy and Maternal High-Fat Diet Impair Mitochondrial Dynamism in the Developing Fetal Rat Heart by Sex-Specific Mechanisms

Infants born to diabetic or obese mothers are at greater risk of heart disease at birth and throughout life, but prevention is hindered because underlying mechanisms remain poorly understood. Using a rat model, we showed that prenatal exposure to maternal diabetes and a high-fat diet caused diastolic and systolic dysfunction, myocardial lipid accumulation, decreased respiratory capacity, and oxidative stress in newborn offspring hearts. This study aimed to determine whether mitochondrial dynamism played a role. Using confocal live-cell imaging, we examined mitochondrial dynamics in neonatal rat cardiomyocytes (NRCM) from four prenatally exposed groups: controls, diabetes, high-fat diet, and combination exposed. Cardiac expression of dynamism-related genes and proteins were compared, and gender-specific differences were evaluated. Findings show that normal NRCM have highly dynamic mitochondria with a well-balanced number of fusion and fission events. Prenatal exposure to diabetes or a high-fat diet impaired dynamism resulting in shorter, wider mitochondria. Mechanisms of impaired dynamism were gender-specific and protein regulated. Females had higher expression of fusion proteins which may confer a cardioprotective effect. Prenatally exposed male hearts had post-translational modifications known to impair dynamism and influence mitophagy-mediated cell death. This study identifies mitochondrial fusion and fission proteins as targetable, pathogenic regulators of heart health in offspring exposed to excess circulating maternal fuels.

Effect of well-controlled gestational diabetes on left ventricular diastolic dysfunction in neonates

BACKGROUND

There are some evidences supporting the relation between gestational diabetes mellitus (GDM) and diastolic dysfunction. The aim of our study was to investigate the effect of well-controlled GDM on morphological and functional myocardium.

MATERIALS AND METHODS

We designed a prospective cross-sectional study to evaluate left ventricular (LV) diastolic function of 60 neonates born from mothers with well-controlled GDM (case group) on days of 3-5 after birth. The infants of diabetic mothers (IDM) group were divided into two groups: diabetic mothers treated only with diet (class A) and group of mothers on medical therapy by insulin or metformin (class B). Traditional echocardiography and pulsed-wave Doppler (PWD), tissue Doppler imaging (TDI) were performed for all the neonates.

RESULTS

The study group consisted of 60 neonates as males (M) = 32, (0.53%) and females (F) = 28, (0.46%). Using M-mode echocardiography, interventricular septum thickness (IVS), and LV mass were significantly higher in IDM than control group (p = .0001). The PWD showed both a significantly more peak mitral flow at early diastolic wave (E) and an early filling deceleration time (E-DT) (p = .0001). Tissue Doppler echocardiography parameters A' (cm/s) (p = .0001), E' (cm/s) (p = .002), and E'/A' ratio (p = .0001), left ventricular myocardial performance index (LVMPI), and isovolumetric relaxation time (IVRT) were outstandingly different between the two groups (p = .0001, respectively). Evaluating the GDM group mothers of class A and class B, no significant difference was noted in PWD or TDI parameters compared with the healthy ones.

CONCLUSIONS

It seems that neonates of mothers with well-controlled GDM are still at increased risk of cardiac hypertrophy, subclinical diastolic dysfunction, and impaired left ventricular relaxation. This can be interpreted that focusing only on glycemic control is not enough to prevent cardiac dysfunction.

Risks of asphyxia-related neonatal complications in offspring of mothers with type 1 or type 2 diabetes: the impact of maternal overweight and obesity

AIMS/HYPOTHESIS

We aimed to compare the risks of severe asphyxia-related neonatal complications in the offspring of mothers with type 1 or type 2 diabetes, and to assess the impact of maternal overweight/obesity on these risks.

METHODS

This was a population-based study of 1,343,751 live-born singleton infants in Sweden between 1997 and 2011, including 5941 and 711 infants of mothers with type 1 and type 2 diabetes, respectively. ORs with 95% CIs were calculated for low Apgar score (0-6) at 5 min after birth, hypoxic ischaemic encephalopathy and neonatal seizures.

RESULTS

The rates of a low Apgar score were 0.9%, 2.6% and 2.1% in the offspring of mothers without diabetes or with type 1 or type 2 diabetes, respectively. After controlling for maternal confounders (including BMI), the risk of a low Apgar score increased in the offspring of mothers with type 1 diabetes (OR 2.67, 95% CI 2.23, 3.20) but not in the offspring of mothers with type 2 diabetes (OR 1.25, 95% CI 0.66, 2.35). The ORs of hypoxic ischaemic encephalopathy or neonatal seizures were increased in the offspring of mothers with type 1 diabetes (OR 3.41, 95% CI 2.58, 4.49) and type 2 diabetes (OR 2.54, 95% CI 1.13, 5.69). Maternal overweight/obesity was a risk factor for asphyxia-related neonatal complications and low Apgar scores in the offspring of mothers with type 1 diabetes and mothers without diabetes.

CONCLUSIONS/INTERPRETATION

The risks of a low Apgar score and severe asphyxia-related neonatal complications are increased in the offspring of mothers with type 1 or type 2 diabetes. Maternal overweight/obesity is an important contributing factor.

Oleanolic acid protects against diabetic cardiomyopathy via modulation of the nuclear factor erythroid 2 and insulin signaling pathways

Oleanolic acid (OL) is a pentacyclic triterpene compound used for the treatment of hepatitis, liver fibrosis and liver cirrhosis. In China, there is no published research on the effect or biological utilization of OL on liver diseases. The aim of the present study was to investigate the protective effects of OL against diabetic cardiomyopathy and its possible mechanism. A rat model of diabetes was established using streptozotocin and the effect of OL on diabetic cardiomyopathy (DCM) was evaluated. The results demonstrated that OL significantly reversed the DCM-induced changes to body weight, heart rate, echocardiography and hemodynamics, phosphorylated-glycogen synthase (GS) and glycogen phosphorylase (GP) activity in diabetic rats (all P<0.01). Treatment of diabetic rats with OL significantly inhibited oxidative stress and activated heme oxygenase (HO)-1/nuclear factor erythroid 2 (Nrf2) signaling in a rat model of diabetes (both P<0.01). The results of the present study indicate that OL protects against DCM through the HO-1/Nrf2 and insulin modulating GS/GP signaling pathways.

Children with transposition of the great arteries: Should they actually be born in Nigeria?

AIM

To describe the clinical and echocardiographic features of Nigerian children with transposition of the great arteries and emphasize the need for collaboration with cardiac centres in the developed countries to be able to salvage the children.

METHODS

Prospective and cross sectional involving consecutive patients diagnosed with transposition of the great arteries using clinical evaluation and echocardiography at the Paediatric Department of Lagos State University Teaching Hospital, Lagos Nigeria as part of a large study between January 2007 and December 2015.

RESULTS

There were 51 cases of transposition of the great arteries within the study period with a male to female ratio of 2:1 and a prevalence of 1.55 per 10000 among population of children who presented to centre during the study. Its proportion amongst children with congenital heart disease was 4.9%, while it was 15.4% among those with cyanotic congenital heart disease. The mean age ± SD of the subjects was 10.3 ± 21.8 mo. Up to 70% of the patients were less than 6 mo of age at initial presentation. The most common mode of presentation was cyanosis. The most common associated intracardiac anomaly was ventricular septal defect which occurred in 56% of the patients.

CONCLUSION

Transposition of the great arteries is as common in Nigeria as in the other parts of the world. The most common mode of presentation was cyanosis. There is an urgent need to establish paediatric cardiac centres in Nigeria if these children are to be salvaged.

DNA methyltransferase 1 rs16999593 genetic polymorphism decreases risk in patients with transposition of great arteries

Complete transposition of the great arteries (TGA) is the most frequent cyanotic heart defect diagnosed in neonates. However, the exact etiology of TGA is unknown. The aim of the present study was to assess the association of TGA pathogenesis with single nucleotide polymorphisms (SNPs) in DNA methyltransferases (DNMTs)-1 and 3a- in Chinese children. We genotyped 5 SNPs (rs16999593, rs16999358, and rs2228611 in DNMT1; and rs2276599 and rs2276598 in DNMT3A) in 206 patients with complete TGA and 252 healthy children. Statistical analysis was performed to explore the association of the 5 SNPs with complete TGA susceptibility. Compared with the T/T and C/C genotypes, the heterozygous genotype C/T of rs16999593 correlated with a decreased risk for complete TGA under codominant (OR=0.46; 95% CI=0.29-0.72), dominant (OR=0.58; 95% CI=0.38-0.88), and overdominant (OR=0.44; 95% CI=0.28-0.68) models. In contrast, the genotype C/C of rs16999593 correlated with a higher risk for TGA under a recessive model (OR=3.15; 95% CI=1.14-8.68) compared with the T/T and C/T genotypes. Furthermore, the TGC, TGT, CGC, and CGT haplotypes of DNMT1 did not differ significantly between the two groups, whereas the frequency of the TAC haplotype was lower in the case group (OR<1; P=0.002). No significant differences in the frequencies of the TC, CC, TT, and CT haplotypes of DNMT3A were found between the two groups. Furthermore, logistic regression showed that sex and the rs16999358 SNP were two independent risk factors for complete TGA. Overall, the C/T genotype of the rs16999593 SNP in DNMT1 might decrease the risk of complete TGA pathogenesis in the Southern Chinese population.

Pregnancy and Infants' Outcome: Nutritional and Metabolic Implications

Pregnancy is a complex period of human growth, development, and imprinting. Nutrition and metabolism play a crucial role for the health and well-being of both mother and fetus, as well as for the long-term health of the offspring. Nevertheless, several biological and physiological mechanisms related to nutritive requirements together with their transfer and utilization across the placenta are still poorly understood. In February 2009, the Child Health Foundation invited leading experts of this field to a workshop to critically review and discuss current knowledge, with the aim to highlight priorities for future research. This paper summarizes our main conclusions with regards to maternal preconceptional body mass index, gestational weight gain, placental and fetal requirements in relation to adverse pregnancy and long-term outcomes of the fetus (nutritional programming). We conclude that there is an urgent need to develop further human investigations aimed at better understanding of the basis of biochemical mechanisms and pathophysiological events related to maternal-fetal nutrition and offspring health. An improved knowledge would help to optimize nutritional recommendations for pregnancy.

Type 2 diabetes mellitus induces congenital heart defects in murine embryos by increasing oxidative stress, endoplasmic reticulum stress, and apoptosis

BACKGROUND

Maternal type 1 and 2 diabetes mellitus are strongly associated with high rates of severe structural birth defects, including congenital heart defects. Studies in type 1 diabetic embryopathy animal models have demonstrated that cellular stress-induced apoptosis mediates the teratogenicity of maternal diabetes leading to congenital heart defect formation. However, the mechanisms underlying maternal type 2 diabetes mellitus-induced congenital heart defects remain largely unknown.

OBJECTIVE

We aim to determine whether oxidative stress, endoplasmic reticulum stress, and excessive apoptosis are the intracellular molecular mechanisms underlying maternal type 2 diabetes mellitus-induced congenital heart defects.

STUDY DESIGN

A mouse model of maternal type 2 diabetes mellitus was established by feeding female mice a high-fat diet (60% fat). After 15 weeks on the high-fat diet, the mice showed characteristics of maternal type 2 diabetes mellitus. Control dams were either fed a normal diet (10% fat) or the high-fat diet during pregnancy only. Female mice from the high-fat diet group and the 2 control groups were mated with male mice that were fed a normal diet. At E12.5, embryonic hearts were harvested to determine the levels of lipid peroxides and superoxide, endoplasmic reticulum stress markers, cleaved caspase 3 and 8, and apoptosis. E17.5 embryonic hearts were harvested for the detection of congenital heart defect formation using India ink vessel patterning and histological examination.

RESULTS

Maternal type 2 diabetes mellitus significantly induced ventricular septal defects and persistent truncus arteriosus in the developing heart, along with increasing oxidative stress markers, including superoxide and lipid peroxidation; endoplasmic reticulum stress markers, including protein levels of phosphorylated-protein kinase RNA-like endoplasmic reticulum kinase, phosphorylated-IRE1α, phosphorylated-eIF2α, C/EBP homologous protein, and binding immunoglobulin protein; endoplasmic reticulum chaperone gene expression; and XBP1 messenger RNA splicing, as well as increased cleaved caspase 3 and 8 in embryonic hearts. Furthermore, maternal type 2 diabetes mellitus triggered excessive apoptosis in ventricular myocardium, endocardial cushion, and outflow tract of the embryonic heart.

CONCLUSION

Similar to those observations in type 1 diabetic embryopathy, maternal type 2 diabetes mellitus causes heart defects in the developing embryo manifested with oxidative stress, endoplasmic reticulum stress, and excessive apoptosis in heart cells.

Heart rate variability in neonates of type 1 diabetic pregnancy

BACKGROUND

Cardiomyopathy is a common finding in offspring of pre-gestational type 1 diabetic pregnancy. Echocardiographic and biochemical evidence of fetal cardiac dysfunction have also been reported. Studies suggest that offspring of diabetic mothers (ODM) undergo a fetal programming effect due to the hyperglycaemic intrauterine milieu which increases their risk of cardiovascular morbidity in adult life. Decreased neonatal heart rate variability (HRV) has been described in association with in-utero growth restriction, prematurity, sudden infant death syndrome and congenital heart disease. The effect of in-utero exposure to hyperglycaemia in diabetic pregnancy on neonatal HRV is unknown.

AIMS

Our aim was to determine if neonatal HRV differs between normal and diabetic pregnancy.

STUDY DESIGN AND SUBJECTS

This was a prospective observational study of 38 patients with pregestational type 1 diabetes and 26 controls. HRV assessment was performed using Powerlab (ADI Instruments Ltd).

OUTCOME MEASURES

Heart rate variability assessment and cord blood sampling for pH and glucose were performed for all neonates. Maternal glycaemic control was assessed via measurement of glycosylated haemoglobin in each trimester in the diabetic cohort.

RESULTS

Neonates of diabetic mothers had evidence of altered heart rate variability, with increased low frequency to high frequency ratio (LF: HF), suggestive of a shift towards sympathetic predominance (p<0.05). This altered HRV was significantly related to fetal acidaemia, cord blood glucose values and maternal glycaemic control during pregnancy (p<0.05).

CONCLUSION

Neonates of pregestational diabetic pregnancy have altered HRV which is related to maternal hyperglycaemia, fetal acidaemia and fetal glycaemia. Exposure of the developing heart to fluctuations in maternal glycaemia with subsequent alterations in HRV may explain why infants of diabetic mothers are at greater risk of cardiovascular disease in later life.

Nomenclature and systems of classification for cardiomyopathy in children

There has been a progressive evolution in systems of classification for cardiomyopathy, driven by advances in imaging modalities, disease recognition, and genetics, following initial clinical descriptions in the 1960s. A pathophysiological classification emerged and was endorsed by World Health Organisation Task Forces in 1980 and 1995: dilated, hypertrophic, restrictive, and arrhythmogenic right ventricular cardiomyopathies; subdivided into idiopathic and disease-specific cardiomyopathies. Genetic advances have increasingly linked "idiopathic" phenotypes to specific mutations, although most linkages exhibit highly variable or little genotype-phenotype correlation, confounded by age-dependent changes and varying penetrance. The following two dominant classification systems are currently in use, with advocates in both continents. First, American Heart Association (2006): "A heterogeneous group of diseases of the myocardium associated with mechanical and/or electrical dysfunction that usually exhibit inappropriate ventricular hypertrophy or dilatation due to a variety of causes that frequently are genetic". These are subdivided to those predominantly involving the heart - primary - due to genetic mutation, including ion channelopathies, acquired disease, or mixed; and those with systemic involvement in other organ systems - secondary. Second, European Society of Cardiology (2008): "A myocardial disorder in which heart muscle is structurally and functionally abnormal… sufficient to cause the observed myocardial abnormality", with subdivision to familial and non-familial, excluding ion channelopathies, and split to specific disease subtypes and idiopathic. Further differences exist in the definitions for hypertrophic cardiomyopathy; however, whichever high-level classification is used, the clinical reality remains phenotype driven. Clinical evaluation and diagnostic imaging dominate initial patient contact, revealing diagnostic red flags that determine further specific tests. Genetic testing is undertaken early. A recent attempt to harmonise these competing systems named the MOGE(S) system, based on descriptive logical nosology, currently remains unproven as a fully practical solution.

Impact of pre-pregnancy diabetes mellitus on congenital anomalies, Canada, 2002-2012

OBJECTIVE

To examine the impact of pre-pregnancy diabetes mellitus (DM) on the population birth prevalence of congenital anomalies in Canada.

METHODS

We carried out a population-based study of all women who delivered in Canadian hospitals (except those in the province of Quebec) between April 2002 and March 2013 and their live-born infants with a birth weight of 500 grams or more and/or a gestational age of 22 weeks or more. Pre-pregnancy type 1 or type 2 DM was identified using ICD-10 diagnostic codes. The association between DM and all congenital anomalies as well as specific congenital anomaly categories was estimated using adjusted odds ratios; the impact was calculated as a population attributable risk percent (PAR%).

RESULTS

There were 118,892 infants with a congenital anomaly among 2,839,680 live births (41.9 per 1000). While the prevalence of any congenital anomaly declined from 50.7 per 1000 live births in 2002/03 to 41.5 per 1000 in 2012/13, the corresponding PAR% for a congenital anomaly related to pre-pregnancy DM rose from 0.6% (95% confidence interval [CI]: 0.4-0.8) to 1.2% (95% CI: 0.9-1.4). Specifically, the PAR% for congenital cardiovascular defects increased from 2.3% (95% CI: 1.7-2.9) to 4.2% (95% CI: 3.5-4.9) and for gastrointestinal defects from 0.8% (95% CI: 0.2-1.9) to 1.4% (95% CI: 0.7-2.6) over the study period.

CONCLUSION

Although there has been a relative decline in the prevalence of congenital anomalies in Canada, the proportion of congenital anomalies due to maternal pre-pregnancy DM has increased. Enhancement of preconception care initiatives for women with DM is recommended.

Stillbirth in the pregnancy complicated by diabetes

Pregestational diabetes currently complicates 4% of pregnancies, while gestational diabetes complicates approximately 8% of pregnancies. Increased risk of stillbirth in diabetic pregnancies has been a well-known and recognized complication for decades. While stillbirth rates for diabetic pregnancies have decreased due to screening, treatment, and antenatal surveillance of these patients, about 4% of all stillbirths remain attributable to diabetes, and diabetic pregnancies continue to be at increased risk for perinatal mortality. The purpose of this article is to review the literature on the epidemiology, pathophysiology, and prevention, as well as future research, of diabetes-associated perinatal mortality.

Maternal Hyperglycemia Directly and Rapidly Induces Cardiac Septal Overgrowth in Fetal Rats

Cardiac septal overgrowth complicates 10-40% of births from diabetic mothers, but perplexingly hyperglycemia markers during pregnancy are not reliably predictive. We thus tested whether fetal exposure to hyperglycemia is sufficient to induce fetal cardiac septal overgrowth even in the absence of systemic maternal diabetes. To isolate the effects of hyperglycemia, we infused glucose into the blood supply of the left but not right uterine horn in nondiabetic pregnant rats starting on gestational day 19. After 24 h infusion, right-sided fetuses and dams remained euglycemic while left-sided fetuses were moderately hyperglycemic. Echocardiograms in utero demonstrated a thickened cardiac septum among left-sided (glucose-exposed, 0.592 ± 0.016 mm) compared to right-sided (control, 0.482 ± 0.016 mm) fetuses. Myocardial proliferation was increased 1.5 ± 0.2-fold among left-sided compared to right-sided fetuses. Transcriptional markers of glucose-derived anabolism were not different between sides. However, left-sided fetuses exhibited higher serum insulin and greater JNK phosphorylation compared to controls. These results show that hyperglycemic exposure is sufficient to rapidly induce septal overgrowth even in the absence of the myriad other factors of maternal diabetes. This suggests that even transient spikes in glucose may incite cardiac overgrowth, perhaps explaining the poor clinical correlation of septal hypertrophy with chronic hyperglycemia.

Predictors of postnatal complications and congenital cardiac diseases in infants of mothers with pregestational and gestational diabetes

AIM

In this study, we aimed to evaluate the postnatal problems of infants of mothers with pregestational and gestational diabetes and the clinical properties of infants who were found to have congenital cardiac disease.

MATERIAL AND METHODS

We retrospectively examined the records of 337 newborns who were followed up with a diagnosis of infant of diabetic mother between January 2010 and January 2012 in our Neonatology Unit. The demographic data of the diabetic mothers and their babies, the postnatal problems of the babies of diabetic mothers and congenital heart diseases found on transthoracic echocardiography were examined.

RESULTS

The patients were classified as group A, B and C in accordance with the recommendations of The American Congress of Obstetricians and Gynecologists (ACOG) according to the type of diabetes. The most common postnatal problems included hyperbilirubinemia, respiratory distress, hypoglycemia and hypocalcemia. The rate of congenital heart disease was found be 17.3% in group A, 50% in group B and 9% in group C. No correlation was found between congenital heart disease and gender, multiple pregnancy, diabetes type, diet treatment, use of oral antidiabetic drugs and drug usage. A positive significant correlation was found between congenital heart disease and genetic disease, murmur, cyanosis and presence of gestational hypertension. It was shown that use of insulin, genetic disease and presence of gestational diabetes increased the risk of congenital heart disease.

CONCLUSIONS

In our study, the overall incidence of congenital heart disease was found to be 24% in infants of diabetic mothers. It should be kept in mind that it is important to investigate the infants of mothers with pregestational and gestational diabetes in terms of the risk of congenital heart disease.

Molecular insight into heart development and congenital heart disease: An update review from the Arab countries

Congenital heart defect (CHD) has a major influence on affected individuals as well as on the supportive and associated environment such as the immediate family. Unfortunately, CHD is common worldwide with an incidence of approximately 1% and consequently is a major health concern. The Arab population has a high rate of consanguinity, fertility, birth, and annual population growth, in addition to a high incidence of diabetes mellitus and obesity. All these factors may lead to a higher incidence and prevalence of CHD within the Arab population than in the rest of the world, making CHD of even greater concern. Sadly, most Arab countries lack appropriate public health measures directed toward the control and prevention of congenital malformations and so the importance of CHD within the population remains unknown but is thought to be high. In approximately 85% of CHD patients, the multifactorial theory is considered as the pathologic basis. The genetic risk factors for CHD can be attributed to large chromosomal aberrations, copy number variations (CNV) of particular regions in the chromosome, and gene mutations in specific nuclear transcription pathways and in the genes that are involved in cardiac structure and development. The application of modern molecular biology techniques such as high-throughput nucleotide sequencing and chromosomal array and methylation array all have the potential to reveal more genetic defects linked to CHD. Exploring the genetic defects in CHD pathology will improve our knowledge and understanding about the diverse pathways involved and also about the progression of this disease. Ultimately, this will link to more efficient genetic diagnosis and development of novel preventive therapeutic strategies, as well as gene-targeted clinical management. This review summarizes our current understanding of the molecular basis of normal heart development and the pathophysiology of a wide range of CHD. The risk factors that might account for the high prevalence of CHD within the Arab population and the measures required to be undertaken for conducting research into CHD in Arab countries will also be discussed.

Elevated neonatal insulin-like growth factor I is associated with fetal hypertrophic cardiomyopathy in diabetic women

OBJECTIVE

We sought to determine if fetal hypertrophic cardiomyopathy (HCM) or cardiac dysfunction is associated with elevated maternal or neonatal insulin-like growth factor (IGF)-I levels in women with diabetes.

STUDY DESIGN

In a prospective cohort study, fetal echocardiogram findings at 36 weeks' gestation in women with pregestational diabetes mellitus were compared to those in women without diabetes mellitus. HCM was defined as septal or free wall thickness ≥5 mm and cardiac dysfunction as a modified myocardial performance index ≥0.43. Cord serum IGF-I levels at delivery were measured with enzyme-linked immunosorbent assay. Neonates with abnormal fetal echocardiogram were followed up until resolution or 6 months of life.

RESULTS

In all, 75 participants completed fetal echocardiography (55 diabetics and 20 controls). In the diabetic group, 33 of 55 (60%) had abnormal fetal echocardiograms with cardiac dysfunction in 21 of 55 (38.2%) and HCM in 8 of 55 (14.5%) and both in 4 of 55 (7.3%). At 6 months of age, 1 of 12 (8%) had persistent HCM. None in the comparison group had abnormal findings. There were no significant clinical differences in those diabetic women with normal vs abnormal fetal echocardiograms. However, among diabetic women, mean neonatal IGF-I was significantly higher in fetuses with HCM (80 ± 16 ng/mL) as compared to those without HCM (61 ± 18 ng/mL), (P < .001).

CONCLUSION

Elevated neonatal IGF-I appears to be associated with fetal HCM in fetuses of diabetic women.

Association between maternal body mass index and congenital heart defects in offspring: a systematic review

The aim of this study was to investigate the relationship between maternal body mass index and all congenital heart defects (CHDs) combined and 11 individual defects. PubMed, ELSEVIER ScienceDirect, and Springer Link (up to February 2013) were searched, and the reference list of retrieved articles was reviewed. Three authors independently extracted the data. The systematic review included 24 studies, 14 of which were included in a metaanalysis. Statistical software was used to perform all statistical analyses. Fixed-effects or random-effects model was used to pool the results of individual study (expressed as odds ratios [ORs] with 95% confidence intervals [CIs]). A dose-response effect was observed between overweight, moderate obesity, and severe obesity and a pregnancy with any CHD (the pooled ORs: OR, 1.08 [95% CI, 1.02-1.15]; OR, 1.15 [95% CI, 1.11-1.20]; and OR, 1.39 [95% CI, 1.31-1.47], respectively) as well as some individual defects such as hypoplastic left heart syndrome, pulmonary valve stenosis, and outflow tract defects. When we excluded mothers with diabetes mellitus, the pooled ORs for all CHDs combined were 1.12 (95% CI, 1.04-1.20) and 1.38 (95% CI, 1.20-1.59) for moderately obese and severely obese, respectively. The highest increased risk was severely obese mothers for tetralogy of Fallot (OR, 1.94; 95% CI, 1.49-2.51). Being underweight did not increase the risk of any of the aforementioned CHDs but did increase the risk of aortic valve stenosis (OR, 1.47; 95% CI, 1.01-2.15]). The results of our study showed that increasing maternal body mass index was associated with an increasing risk of CHDs; severe obesity was an even greater risk factor for the development of CHDs.

Analysis of mutations in 7 candidate genes for dextro-Transposition of the great arteries in Chinese population

BACKGROUND

Transposition of great arteries (TGA) represents the most frequent cyanotic heart defect diagnosed in the neonatal period. Several genes had been identified to be associated with the pathogenesis of dextro-transposition of the great arteries (d-TGA). These genes are located in different chromosomes and their mutations can only explain few clinical cases. Besides, no genetic scan for TGA has been implemented in China.

METHODS

To evaluate whether aberrations in any of the 13 reported mutations in seven genes (MED13L, ZIC3, CFC1, NODAL, FOXH1, GDF1 and NKX2-5) could completely or in part be the genetic component involved in TGA in Chinese population, we screened 102 Chinese patients with d-TGA by direct sequencing for mutations within the seven genes.

RESULTS

We found none of the reported 13 mutations in those 102 Chinese d-TGA patients.

CONCLUSIONS

These reported 13 mutations may not be a common cause of d-TGA in Chinese population due to racial variation and genetic heterogeneity of TGA. New approaches including the whole exome sequencing technology are required to effectively identify genetic variants in TGA patients in China.

Update on neonatal hypoglycemia

PURPOSE OF REVIEW

Neonatal hypoglycemia is one of the most common biochemical abnormalities encountered in the newborn. However, controversy remains surrounding its definition and management especially in asymptomatic patients.

RECENT FINDINGS

New information has been published that describes the incidence and timing of low glucose concentrations in the groups most at risk for asymptomatic neonatal hypoglycemia. Furthermore, one large prospective study failed to find an association between repetitive low glucose concentrations and poor neurodevelopmental outcomes in preterm infants. But hypoglycemia due to hyperinsulinism, especially genetic causes, continued to be associated with brain injury. New advances were made in the diagnosis and management of hyperinsulinism, including acquired hyperinsulinism in small for gestational age infants and others. Continuous glucose monitoring remains an attractive strategy for future research in this area.

SUMMARY

The fundamental question of how best to manage asymptomatic newborns with low glucose concentrations remains unanswered. Balancing the risks of overtreating newborns with low glucose concentrations who are undergoing a normal transition following birth against the risks of undertreating those in whom low glucose concentrations are pathological, dangerous, and/or a harbinger of serious metabolic disease remains a challenge.

Stillbirth: the heart of the matter

We evaluated 2,083 cases within the Wisconsin Stillbirth Service Program (WiSSP) that had autopsy reports or ultrasound data relevant to the heart. Of these, 167/1,782 (9.4%) stillbirths after 20 weeks and 11/301 (3.7%) miscarriages <20 weeks had congenital heart disease (CHD). Cases were classified by type of heart defect and whether it related to cause of death. Among cardiac anomalies that contributed significantly to fetal death, 125/151 (83%) were associated with underlying conditions or syndromes, nearly half of which were chromosomal. The most common forms of CHD in stillborns were severe cyanotic lesions (3%), then ventricular (2.6%) and atrial (1.9%) septal defects. Compared to livebirths, this represents a shift toward more severe cardiac lesions, although all comparable categories, including non-lethal conditions such as atrial septal defect, are more common in stillbirths. Clinical cardiomyopathy was identified as cause of death in 1.2% of stillborns. Cardiomegaly, occurring in 26.7% of all cases and 76.7% of infants born to diabetic mothers, may represent undiagnosed cardiomyopathy and/or may decrease fetal tolerance of hypoxia. In contrast, 78.5% of Turner syndrome infants, all <32 weeks, had small hearts. More attention to cardiac findings can lead to increased understanding of stillbirth causes. Based on our findings, we recommend chromosome studies on all stillbirths and close attention to the heart during second trimester ultrasounds, with chromosome studies offered if CHD is found. Consideration of heart size can result in prenatal identification of infants at risk for stillbirth, particularly large hearts in fetuses of diabetic mothers in the third trimester, which may identify fetal cardiomyopathy before it becomes life-threatening.

Cardiomyopathy in offspring of pregestational diabetic mouse pregnancy

PURPOSE

To investigate cardiomyopathy in offspring in a mouse model of pregestational type 1 diabetic pregnancy.

METHODS

Pregestational diabetes was induced with STZ administration in female C57BL6/J mice that were subsequently mated with healthy C57BL6/J males. Offspring were sacrificed at embryonic day 18.5 and 6-week adolescent and 12-week adult stages. The size and number of cardiomyocyte nuclei and also the extent of collagen deposition within the hearts of diabetic and control offspring were assessed following cardiac tissue staining with either haematoxylin and eosin or Picrosirius red and subsequently quantified using automated digital image analysis.

RESULTS

Offspring from diabetic mice at embryonic day 18.5 had a significantly higher number of cardiomyocyte nuclei present compared to controls. These nuclei were also significantly smaller than controls. Collagen deposition was shown to be significantly increased in the hearts of diabetic offspring at the same age. No significant differences were found between the groups at 6 and 12 weeks.

CONCLUSIONS

Our results from offspring of type 1 diabetic mice show increased myocardial collagen deposition in late gestation and have increased myocardial nuclear counts (hyperplasia) as opposed to increased myocardial nuclear size (hypertrophy) in late gestation. These changes normalize postpartum after removal from the maternal intrauterine environment.

Hypertrophic cardiomyopathy in neonates with congenital hyperinsulinism

INTRODUCTION

Hypertrophic cardiomyopathy (HCM) is a well-recognised complication in infants of diabetic mothers and is attributed to a compensatory increase in fetal insulin secretion. Infants with congenital hyperinsulinism have excessive prenatal and postnatal insulin secretion due to defects in pathways of insulin secretion (most commonly the KATP channel). HCM has been reported in a few neonates with hyperinsulinism, but its extent and risk factors for its development have not been evaluated.

METHODS

Retrospective chart review of infants, age <3 months, with congenital hyperinsulinism managed by Children's Hospital of Philadelphia over a 3.5-year period.

DATA

Gestational age, birth weight, hyperinsulinism form and treatments, echocardiogram results, cardiac/respiratory complications.

RESULTS

68 infants were included, 58 requiring pancreatectomy for diffuse (n=28) or focal (n=30) disease, 10 were diazoxide-sensitive. Twenty-five had echocardiograms performed. Ten had HCM, all of whom required pancreatectomy and eight of whom had confirmed ATP-sensitive potassium-hyperinsulinism. Subjects with HCM had younger gestational age 36(32, 38) than their surgical counterparts without HCM 38 (31.6, 43), p=0.02.

DISCUSSION

HCM appears common in infants with severe hyperinsulinism. Routine echocardiogram and EKG of at-risk newborns should be considered. Fetal hyperinsulinism is the likely mediating factor for HCM in HI infants.

Association between maternal chronic conditions and congenital heart defects: a population-based cohort study

BACKGROUND

This study quantifies the association between maternal medical conditions/illnesses and congenital heart defects (CHDs) among infants.

METHODS AND RESULTS

We carried out a population-based study of all mother-infant pairs (n=2,278,838) in Canada (excluding Quebec) from 2002 to 2010 using data from the Canadian Institute for Health Information. CHDs among infants were classified phenotypically through a hierarchical grouping of International Statistical Classification of Diseases and Related Health Problems, 10th Revision, Canada codes. Maternal conditions such as multifetal pregnancy, diabetes mellitus, hypertension, and congenital heart disease were defined by use of diagnosis codes. The association between maternal conditions and CHDs and its subtypes was modeled using logistic regression with adjustment for maternal age, parity, residence, and other factors. There were 26 488 infants diagnosed with CHDs at birth or at rehospitalization in infancy; the overall CHD prevalence was 116.2 per 10,000 live births, of which the severe CHD rate was 22.3 per 10,000. Risk factors for CHD included maternal age ≥40 years (adjusted odds ratio [aOR], 1.48; 95% confidence interval [CI], 1.39-1.58), multifetal pregnancy (aOR, 4.53; 95% CI, 4.28-4.80), diabetes mellitus (type 1: aOR, 4.65; 95% CI, 4.13-5.24; type 2: aOR, 4.12; 95% CI, 3.69-4.60), hypertension (aOR, 1.81; 95% CI, 1.61-2.03), thyroid disorders (aOR, 1.45; 95% CI, 1.26-1.67), congenital heart disease (aOR, 9.92; 95% CI, 8.36-11.8), systemic connective tissue disorders (aOR, 3.01; 95% CI, 2.23-4.06), and epilepsy and mood disorders (aOR, 1.41; 95% CI, 1.16-1.72). Specific CHD subtypes were associated with different maternal risk factors.

CONCLUSIONS

Several chronic maternal medical conditions, including diabetes mellitus, hypertension, connective tissue disorders, and congenital heart disease, confer an increased risk of CHD in the offspring.

A nondysraphic paraspinal mass and a ventricular septal defect: unusual components of diabetes-induced mesodermal derangement

Solitary paraspinal masses in the pediatric age group commonly occur secondary to spinal dysraphism, chronic inflammatory conditions, and tumors. We describe the unusual case of a 10-year-old boy with a nondysraphic, paraspinal mass that had occurred secondary to congenital spinal epidural lipomatosis (SEL) in the setting of poorly controlled maternal type-I diabetes mellitus. The mass was picked up along with a ventricular septal defect (VSD) on an antenatal ultrasonogram. This is the first report in literature of SEL presenting as a solitary paraspinal mass at birth, and in the unusual setting of an antenatal mesodermal derangement that simultaneously engendered a VSD.

Impact of prenatal risk factors on congenital heart disease in the current era

Background

The healthcare burden related to congenital heart disease (CHD) is increasing with improving survival. We assessed changing trends in prenatal risk factors for CHD in the current era in a Canadian cohort.

Methods and Results

CHD patients <18 years old (n=2339) and controls without structural heart disease (n=199) were prospectively enrolled in an Ontario province‐wide biobank registry from 2008–2011. Family history, frequency of extra‐cardiac anomalies (ECAs), and antenatal risk factors were assessed. Temporal trends were analyzed and associations with CHD were measured using linear and logistic regression. Family history of CHD and frequency of major ECAs was higher in cases versus controls (P<0.001). Despite an increase in genetic testing in the recent era, only 9.5% of cases with CHD had a confirmed genetic diagnosis. Yield of genetic testing (ie, frequency of abnormal results) was higher in familial and syndromic cases. There was an increase in parental age at conception, maternal prepregnancy body mass index, maternal urinary tract infections, type 1 diabetes, and exposure to nonfertility medications during pregnancy from 1990–2011. Later year of birth, family history of CHD, presence of major ECAs, maternal smoking during pregnancy, and maternal medication exposure were associated with increased odds of CHD (P<0.05 for all). Advanced parental age was associated with increased odds of CHD caused by genetic abnormalities.

Conclusions

The increase in prenatal risk factors for CHD highlights the need for more rigorous ascertainment of genetic and environmental factors including gene‐environment interactions that contribute to CHD.

Disorders in glucidic metabolism and congenital heart diseases: detection and prevention

The identification of gestational diabetes (GDM) through appropriate screening and its subsequent treatment have not been demonstrated to limit neonatal malformations to date. This study aimed to detect congenital heart diseases in newborns of mothers with GDM by evaluating the existence of a correlation with maternal glycemic control. This observational prospective study investigated newborns of mothers with GDM enrolled during a period of 9 months. Four subgroups were considered according to the type of maternal glucidic alteration during pregnancy and the home treatment: impaired glucose tolerance, insulin-dependent gestational diabetes mellitus (IDDM), non-insulin-dependent gestational diabetes mellitus (NIDDM), and gestational diabetes not controlled (NC: untreated diabetes). Student's t test was used to compare the subgroups. The study enrolled 65 newborns (30 boys) born to 82 of mothers with impaired glucidic metabolism. Patent ductus arteriosus was observed in 11 patients (16.9 %), pulmonary stenosis of mild grade in 4 patients ( 6.2 %), and hypertrophy of the ventricular septum in 22 patients (33.8 %). A total of 14 patients had increased thickness in the left ventricle posterior wall, and 17 patients had an abnormal electrocardiogram. Hyperglycemia can influence the development of the fetal heart, affecting both its structure and its function. A treatment with insulin for women with GDM is supported by the study data.