Prenatal diagnosis and treatment planning of congenital heart defects-possibilities and limits

Placental weight in pregnancies complicated by fetal congenital heart defects

INTRODUCTION

Congenital heart defects (CHD) are the most common malformations. Fetuses with CHD are at an increased risk of being born small for gestational age (SGA), suggesting an impaired placental function. Our aim was to investigate the interdependence between fetal heart and placenta in pregnancies affected by isolated CHD.

METHODS

This was a retrospective cohort study at a tertiary referral center. All singleton pregnancies with suspected fetal CHD between 2009 and 2020 were included. Confirmed CHD were allocated to one of six subgroups according to neonatal echocardiography or autopsy. Birth weight (b), placental weight (p), b/p ratio were calculated and compared between the subgroups, respectively.

RESULTS

302 fetuses with confirmed CHD were analyzed. The overall incidence of SGA neonates with isolated CHD was 33/161 (20.4 %), while 28.4 % (38/134) of CHD placental weights were below the 10th percentile, with the highest incidence in cases with isolated univentricular (42.9 %) and left-sided (37.1 %) cardiac lesions. Mean b/p ratio in isolated cases was 5.32 (SD ± 1.51), and 23/134 (17.2 %) were > 90th percentile. 11/302 (3.6 %) of pregnancies were affected by preeclampsia. All neonates were SGA and 7/10 (70 %) placental weights were < 10th percentile.

CONCLUSION

The incidence of small placentas, SGA and preeclampsia is increased in pregnancies with fetal CHD. Disturbances in fetal cardio-placental hemodynamics may alter the development of the villous tree resulting in small placentas and fetuses, suggesting a second hit on the placenta, particularly in preeclampsia. Pregnancies with fetal CHD should be followed more closely for placental dysfunction and impaired fetal growth.

Prenatal Diagnosis of Congenital Heart Disease: The Crucial Role of Perinatal and Delivery Planning

Although most congenital heart defects (CHDs) are asymptomatic at birth, certain CHD lesions are at significant risk of severe hemodynamic instability and death if emergent cardiac interventions are not performed in a timely fashion. Therefore, accurate identification of at-risk fetuses and appropriate delivery resource planning according to the degree of anticipated hemodynamic instability is crucial. Fetal echocardiography has increased prenatal CHD detection in recent years due to advancements in ultrasound techniques and improved obstetrical cardiac screening protocols, enabling the prediction of newborns' hemodynamic status. This assessment can guide multidisciplinary resource planning for postnatal care, including selection of delivery site, delivery room management, and transport to a cardiac center based on CHD risk severity. This review will discuss fetal cardiovascular physiology and the circulatory changes that occur at the time of and immediately following birth, outline fetal echocardiographic findings used to risk-stratify newborns with CHDs, and outline principles for neonatal resuscitation and initial transitional care in neonates with these complex CHD lesions.

Fetal electrocardiography and artificial intelligence for prenatal detection of congenital heart disease

INTRODUCTION

This study aims to investigate non-invasive electrocardiography as a method for the detection of congenital heart disease (CHD) with the help of artificial intelligence.

MATERIAL AND METHODS

An artificial neural network was trained for the identification of CHD using non-invasively obtained fetal electrocardiograms. With the help of a Bayesian updating rule, multiple electrocardiographs were used to increase the algorithm's performance.

RESULTS

Using 122 measurements containing 65 healthy and 57 CHD cases, the accuracy, sensitivity, and specificity were found to be 71%, 63%, and 77%, respectively. The sensitivity was however 75% and 69% for CHD cases requiring an intervention in the neonatal period and first year of life, respectively. Furthermore, a positive effect of measurement length on the detection performance was observed, reaching optimal performance when using 14 electrocardiography segments (37.5 min) or more. A small negative trend between gestational age and accuracy was found.

CONCLUSIONS

The proposed method combining recent advances in obtaining non-invasive fetal electrocardiography with artificial intelligence for the automatic detection of CHD achieved a detection rate of 63% for all CHD and 75% for critical CHD. This feasibility study shows that detection rates of CHD might improve by using electrocardiography-based screening complementary to the standard ultrasound-based screening. More research is required to improve performance and determine the benefits to clinical practice.

Utility of Fetal Echocardiography with Acute Maternal Hyperoxygenation Testing in Assessment of Complex Congenital Heart Defects

Fetal echocardiography is an excellent tool for accurately assessing the anatomy and physiology of most congenital heart defects (CHDs). Knowledge gathered from a thorough initial fetal echocardiogram and serial assessment assists with appropriate perinatal care planning, resulting in improved postnatal outcomes. However, fetal echocardiography alone provides limited information about the status of the pulmonary vasculature, which can be abnormal in certain complex CHDs with obstructed pulmonary venous flow (hypoplastic left heart syndrome with restrictive atrial septum) or excessive pulmonary artery flow (d-transposition of the great arteries, usually with a restrictive ductus arteriosus). Fetuses with these CHDs are at high risk of developing severe hemodynamic instability with the immediate transition from prenatal to postnatal circulatory physiology at the time of birth. Adjunctive use of acute maternal hyperoxygenation (MH) testing in such cases can help determine pulmonary vascular reactivity in prenatal life and better predict the likelihood of postnatal compromise and the need for emergent intervention. This comprehensive review discusses the findings of studies describing acute MH testing in a diverse spectrum of CHDs and congenital diagnoses with pulmonary hypoplasia. We review historical perspectives, safety profile, commonly used clinical protocols, limitations, and future directions of acute MH testing. We also provide practical tips on setting up MH testing in a fetal echocardiography laboratory.

Delivery Outcome of Fetuses with Congenital Heart Disease-Is It Influenced by Prenatal Diagnosis?

Objective: The objective of this study is to assess the delivery outcomes of neonates with congenital heart defects (CHD), and to explore the effect of prenatal diagnosis on these outcomes. Methods: A retrospective study including singleton deliveries between 2011 and 2020. All singleton neonates delivered at >24 weeks of gestation were included in this study. Fetuses with known prenatal anomalies other than CHD were excluded from this study. Pregnancy and neonatal outcomes were analyzed. A comparison was made between pregnancies with CHD and controls; and between pregnancies with prenatal diagnosis of CHD and postnatal diagnosis of CHD. Results: A total of 1598 neonates with CHD (688, 43.1% diagnosed prenatally) comprised the study group, compared to 85,576 singleton controls. Pregnancies with CHD had significantly increased BMI before pregnancy, suffered more from diabetes and chronic hypertension, had more inductions of labor, and had more cesarean deliveries (CD) including both elective CD and urgent CD due to non-reassuring fetal monitor (NRFHR) (OR = 1.75; 95%CI 1.45−2.14). Prenatal diagnosis of CHD is associated with a significant increased rate of induction of labor compared to postnatal diagnosis of CHD (OR = 1.59; 95% CI 1.15−2.22), but did not affect the mode of delivery including the rate of CD and CD due to non-reassuring fetal heart rate (NRFHR). Gestational age at birth and birthweight were significantly lower in pregnancies with CHD compared to controls, with no difference between prenatal to postnatal diagnosis of the anomaly. Neonates with CHD had a higher incidence of hypoxic ischemic encephalopathy and seizures compared to controls without any impact by prenatal diagnosis. Conclusion: Prenatal diagnosis of CHD is associated with an increased rate of induction of labor, with no increased rate of CD and CD due to NRFHR. The 5-min Apgar score is lower in pregnancies with postnatal diagnosis of CHD.

Prenatal Detection of Congenital Heart Diseases Using Echocardiography: 12-Year Results of an Improving Program With 9782 Cases

Background

A provincial program combining the effect of a government investment in prenatal screening and a specialized cardiac center was introduced in 2004, to improve prenatal diagnosis by echocardiography for congenital heart diseases (CHDs) in the Guangdong Registry of Congenital Heart Disease, China.

Objectives

To evaluate the effects of this program on the prenatal diagnosis rate (PDR) by echocardiography and termination of pregnancy (TOP).

Methods

A retrospective study from 2004-2015 included 9782 fetuses and infants diagnosed with CHDs. The PDR was calculated for major and minor CHDs during pre-, mid- and post-program time-intervals. Multivariable logistic regression was utilized to analyze the associations between program implementation and the timing of CHD diagnosis (prenatal vs. postnatal) by different hospital levels. The rate for TOP were also evaluated.

Results

The PDR increased by 44% for major CHDs in the post-program interval relative to the pre-program interval. The three most frequently diagnosed subtypes prenatally were hypoplastic left heart syndrome (84%), double outlet right ventricle (83%) and severe pulmonary stenosis (82%). Participants with a high school education experienced a greater increase in PDR than those without a high school education. The odds for a prenatal vs. a postnatal diagnosis for major CHD were greater after introduction of the program than before (adjusted odd ratio= 20.95, 95% CI:2.47, 178.06 in secondary hospitals; and adjusted odd ratio=11.65, 95% CI:6.52, 20.81 in tertiary hospitals). The TOP rate decreased from 52.3% pre-program to 19.6% post-program among minor CHD fetuses with a prenatal diagnosis (P for trend =0.041). A lower proportion of TOP were attributed to minor CHDs after the program.

Conclusions

The program combining the advantages of government investment and a specialized cardiac center appeared to increase the PDR by echocardiography for CHDs in an unselected population. The TOP rate among minor cases with prenatal diagnosis declined significantly after implementation of the program.

Early Results of the Persian Registry of Cardiovascular Disease/Congenital Heart Disease (PROVE/CHD) in Isfahan

Background: In 2016, a prospective registry for pediatric patients with congenital heart disease (CHD) was established in Isfahan, Iran. Data on pediatric CHD in Iran are scant; accordingly, we aimed to report the early results of the Persian Registry Of cardioVascular diseasE (PROVE/CHD) Registry in Isfahan. Methods: All patients with CHD and associated defects diagnosed by pediatric cardiologists were assessed via echocardiography for inclusion in the present study between late 2016 and August 2019. The participants' sociodemographic characteristics, maternal history, birth history, medical history, current clinical presentations in the clinic or hospital, paraclinical data, cardiac diagnoses based on the International Classification of Diseases, 10th Revision (ICD-10), disease management plans, and medications were entered into a questionnaire by the subjects' parents/legal custodians and physicians and then transferred to the PROVE/CHD Registry. Results: The PROVE/CHD registry encompasses 1252 patients with CHD (49.9% male) at a mean age of 6.50±6.36 years. The most frequent cardiac diagnoses were ventricular septal defect (39.3%), atrial septal defect (29.7%), patent ductus arteriosus (25.4%), pulmonary stenosis (11.0%), tetralogy of Fallot (6.1%), coarctation of the aorta (5.4%), and aortic stenosis (5.1%), respectively. The most frequent interventions were patent ductus arteriosus closure (4.3%), atrial septal defect closure (3.6%), pulmonary valvuloplasty (2.2%), coarctation of the aorta angioplasty (1.9%), and ventricular septal defect closure (1.1%), correspondingly. The approximate corresponding rates of corrective and palliative surgeries were 32.0% and 13.1%. The corrective surgeries were mainly comprised of ventricular septal defect closure (7.8%), patent ductus arteriosus closure (7.3%), atrial septal defect closure (5.1%), and tetralogy of Fallot repair (3.8%), respectively. The palliative surgeries mainly consisted of the Glenn shunt (9.0%) and pulmonary artery banding (3.6%). Conclusion: The PROVE/CHD Registry collects data on pediatric patients with CHD. The results of this registry can provide epidemiological data and a set of homogeneously defined cases for further studies.

Comparison of the 1-year survival rate in infants with congenital heart disease diagnosed by prenatal and postnatal ultrasound: A retrospective study

The impact of prenatal diagnosis on the survival outcome of infants with congenital heart disease (CHD) is still unclear. This study aimed to compare the 1-year survival rate between the prenatally and postnatally diagnosed infants with CHDs.A single-center population-based retrospective cohort study was performed on data from all infants diagnosed with CHD born between January 1998 and December 2017. Among infants with isolated CHDs, the 1-year Kaplan-Meier survival probabilities for prenatal and postnatal diagnosis were estimated. Cox proportional hazard ratios were adjusted for critical CHD (CCHD) status and gestational age.A total of 424 (40 prenatally and 384 postnatally) diagnosed infants with CHDs were analyzed. Compared with non-CCHDs, infants with CCHDs were more likely to be prenatally diagnosed (55.0% vs 18.0%; P < .001). Among the 312 infants with isolated CHDs, the 1-year survival rate for the prenatally diagnosed was significantly lower than postnatally diagnosed (77.1% vs 96.1%; P < .001). For isolated CCHDs, the 1-year survival rate for the prenatally diagnosed was significantly lower than postnatally diagnosed (73.4% vs 90.0%; P < .001). The 1-year survival rate was increased with the increase of age at diagnosis. Among infants with isolated CHDs and CCHDs, the adjusted hazard ratios for 1-year mortality rates for the prenatally versus postnatally diagnosed were 2.554 (95% confidence interval [CI], 1.790, 3.654; P < .001) and 2.538 (95% CI: 1.796, 3.699; P < .001), respectively.Prenatal diagnosis is associated with lower 1-year survival rate for infants with isolated CCHDs. This could probably due to variation in the disease severity among the CCHD subtypes.

Antenatal and Perioperative Mechanisms of Global Neurological Injury in Congenital Heart Disease

Congenital heart defects (CHD) is one of the most common types of birth defects. Thanks to advances in surgical techniques and intensive care, the majority of children with severe forms of CHD survive into adulthood. However, this increase in survival comes with a cost. CHD survivors have neurological functioning at the bottom of the normal range. A large spectrum of central nervous system dysmaturation leads to the deficits seen in critical CHD. The heart develops early during gestation, and CHD has a profound effect on fetal brain development for the remainder of gestation. Term infants with critical CHD are born with an immature brain, which is highly susceptible to hypoxic-ischemic injuries. Perioperative blood flow disturbances due to the CHD and the use of cardiopulmonary bypass or circulatory arrest during surgery cause additional neurological injuries. Innate patient factors, such as genetic syndromes and preterm birth, and postoperative complications play a larger role in neurological injury than perioperative factors. Strategies to reduce the disability burden in critical CHD survivors are urgently needed.

Fetal cardiac function by three-dimensional ultrasound using 4D-STIC and VOCAL - an update

Three- and four-dimensional (3D/4D) ultrasonography with spatio-temporal image correlation (4D-STIC) allows obtaining fetal cardiac volumes and their static and real-time analysis in multiplanar and rendering modes. Cardiac biometrics and Doppler-echocardiographic parameters for evaluation of fetal heart function, including cardiac output and stroke volume, can be analyzed using M-mode, two-dimensional (2D), and 3D/4D cardiac ultrasound. In recent years, functional echocardiography has been used to study fetuses without a structurally cardiac defect but who are at risk of heart failure due to the presence of extra-cardiac conditions, such as, fetal growth restriction, tumors/masses, twin-to-twin transfusion syndrome, fetal anemia (Rh alloimmunization), congenital infections, or maternal diabetes mellitus. The assessment of cardiac function provides important information on hemodynamic status and can help optimize the best time for delivery and reduce perinatal morbidity and mortality. Since 2003, with the advent of the 4D-STIC software, it is possible to evaluate the fetal heart in multiplanar, and rendering modes. This technology associated with virtual organ computer-aided analysis (VOCAL) enables determining the ventricular volume (end-diastole, end-systole), the stroke-volume, the ejection fraction, and the cardiac output of each ventricle. Since 2004, several studies demonstrated that the 4D-STIC and VOCAL had good reproducibility to measure cardiac volumes This study reviews published studies that evaluated the fetal cardiac function by 3D ultrasound using 4D-STIC and VOCAL software.

Tetralogy of Fallot in Spain: a nationwide registry-based mortality study across 36 years

BACKGROUND

Tetralogy of Fallot (TOF) is the most frequent cyanotic congenital heart defect. TOF mortality has fallen remarkably in recent years due to therapeutic advances. Accordingly, the aim of this study was to assess temporal and spatial variability in TOF-related mortality in Spain across the period 1981-2016, using data drawn from the nationwide population-based registry.

METHODS

Annual deaths due to TOF were sourced from the Spanish National Institute of Statistics database by reference to International Classification of Diseases (ICD), 9th and 10th Revision codes, namely, ICD-9 code 745.2 (period 1981-1998) and ICD-10 code Q21.3 (period 1999-2016). Age-specific and age-adjusted mortality rates were calculated, as were standardised mortality ratios (SMRs) by province, district and municipality for the period 1999-2016.

RESULTS

A total of 1035 deaths were attributed to TOF (57.78% of them were men and 42.22% were women). The age-adjusted mortality rate ranged from 0.75 per 1,000,000 inhabitants (95% confidence interval [CI]: 0-1.36) in 1981 to 0.03 per 1,000,000 (95% CI: 0.01-0.06) in 2016 for both sexes. In 2011, there was a change in the mortality trend, with a significant decrease of 49.22% per year (p < 0.001). In terms of geographical analysis, some areas with a significantly higher risk of TOF mortality were identified in the south of Spain, though no specific spatial pattern was in evidence.

CONCLUSION

The decrease in TOF mortality may be related to improvements in diagnostic and treatment techniques. More studies are needed to analyse regions with a higher mortality risk, in order to improve medical planning and resource allocation, and identify risk factors and preventive measures.

Noninvasive prenatal testing for congenital heart disease - cell-free nucleic acid and protein biomarkers in maternal blood

Context: Congenital heart disease (CHD) is the most common fetal malformation. Prenatal ultrasonography is routinely applied for the screening of CHD but many factors influence its diagnostic accuracy. The introduction of new biomarkers could facilitate the identification of high-risk pregnancies.Objective: In our review, our aim was to collect expression studies of cell-free nucleic acids and proteins in maternal circulation. Syndromic CHDs which can be detected by noninvasive prenatal testing (NIPT) techniques were also discussed.Methods: PubMed and Web of Science databases were screened for studies where the levels of potential CHD biomarkers were measured in maternal blood samples. Available NIPT tests were collected from the providers' resources.Results: There are nine CHD-associated chromosomal abnormalities, five aneuploidies, and four microdeletions, which are included in NIPT panels. We found eight articles from which five included the analysis of specific cell-free RNA expression and three measurements of protein levels.Conclusions: Most of the common heart-related chromosomal aberrations can be diagnosed by NIPT. Specific cell-free RNAs and circulating proteins seem to be potential biomarkers for fetal CHDs. The application of these new biomarkers could improve the detection rate at early pregnancy, making it possible to provide optimal perinatal and perioperative management.

Recommendations for Prenatal Echocardiography: A Report from International Prenatal Cardiology Collaboration Group

International Prenatal Cardiology Collaboration Group (IPCCG) links specialists from prenatal cardiology all over the world. In this recommendation we would like to focus on the fetal/prenatal echocardiography official report. So far many recommendations focused mainly on technical aspects of the fetal heart examination.

Familial Aggregation and Heritability of Congenital Heart Defects

BACKGROUND

Congenital heart defects (CHD) are known to cluster within families, but existing evidence varies for the estimates of familial relative risk (RR). We aimed to examine familial aggregation and heritability of CHD in the general population of Taiwan.

METHODS AND RESULTS

We conducted a population-based family study using the Taiwan National Health Insurance (NHI) research database. Individuals with affected first-degree (n=295,636) or second-degree (n=73,985) relatives were identified from all NHI beneficiaries (n=23,422,955) registered in 2012. Diagnoses of CHD for all study subjects were ascertained between January 1, 1996 and December 31, 2012. Having a twin, a first-degree relative and an affected second-degree relative were associated with an adjusted RR of 12.03 (11.59-12.49), 4.91 (4.85-4.97) and 1.21 (1.14-1.28) for CHD, respectively. Individuals with 1 affected first-degree relative had a RR of 4.78 (4.72-4.84), and those with ≥2 had an RR of 7.10 (6.77-7.45) for CHD. The estimated accountability for phenotypic variance of CHD was 37.3% for familial transmission and 62.8% for non-shared environmental factors.

CONCLUSIONS

Our results indicated that CHD tend to cluster within families, and approximately one-third of phenotypic variance was explained by familial factors.

Role of HDLive in Imaging the Fetal Heart

HDLive is a rendering methodology that generates realistic images of the human fetus from sonographic data. The objective of this study is to demonstrate the utility of high-definition live in evaluating fetal heart especially in the first trimester (11-14-week) scan. The normal atrioventricular valve and its abnormalities along with septal defects can be vividly demonstrated with this technique, and eight cases with cardiac defects are illustrated. Its use in the first-trimester evaluation of heart would give a better perspective of the cardiac malformation, which provides the opportunity for counseling options early in pregnancy.

A home-based exercise program for children with congenital heart disease following interventional cardiac catheterization: study protocol for a randomized controlled trial

Background

Cardiac catheterization has opened an innovative treatment field for cardiac disease; this treatment is becoming the most popular approach for pediatric congenital heart disease (CHD) and has led to a significant growth in the number of children with cardiac catheterization. Unfortunately, based on evidence, it has been demonstrated that the majority of children with CHD are at an increased risk of “non-cardiac” problems. Effective exercise therapy could improve their functional status significantly. As studies identifying the efficacy of exercise therapy are rare in this field, the aims of this study are to (1) identify the efficacy of a home-based exercise program to improve the motor function of children with CHD with cardiac catheterization, (2) reduce parental anxiety and parenting burden, and (3) improve the quality of life for parents whose children are diagnosed with CHD with cardiac catheterization through the program.

Methods/design

A total of 300 children who will perform a cardiac catheterization will be randomly assigned to two groups: a home-based intervention group and a control group. The home-based intervention group will carry out a home-based exercise program, and the control group will receive only home-based exercise education. Assessments will be undertaken before catheterization and at 1, 3, and 6 months after catheterization. Motor ability quotients will be assessed as the primary outcomes. The modified Ross score, cardiac function, speed of sound at the tibia, functional independence of the children, anxiety, quality of life, and caregiver burden of their parents or the main caregivers will be the secondary outcome measurements.

Discussion

The proposed prospective randomized controlled trial will evaluate the efficiency of a home-based exercise program for children with CHD with cardiac catheterization. We anticipate that the home-based exercise program may represent a valuable and efficient intervention for children with CHD and their families.

Trial registration

http://www.chictr.org.cn/ on: ChiCTR-IOR-16007762. Registered on 13 January 2016.

Electronic supplementary material

The online version of this article (doi:10.1186/s13063-016-1773-7) contains supplementary material, which is available to authorized users.

Prevalence and risk factors of congenital heart defects among live births: a population-based cross-sectional survey in Shaanxi province, Northwestern China

BACKGROUND

Nearly half of the population of Northwest China live in Shaanxi province, but population-based data on the epidemiologic characteristics of congenital heart defects (CHD) in this population is limited. The study aimed to investigate the prevalence and epidemiologic characteristics of the CHD among infants born between 2010 and 2013 in Shaanxi province.

METHODS

Infants born between 2010 and 2013 in Shaanxi province were surveyed using a stratified multi-stage sampling method. Participant characteristics were recorded by questionnaire, medical records were reviewed and CHD was diagnosed using a specialized neonatal echocardiography. A Poisson regression model was applied to assess the association between any CHD and possible risk factors.

RESULTS

A total of 29098 live infants were surveyed with an overall prevalence of 76.0 (95% CI: 66.3, 86.7) per 10000 live infants. The prevalence of major and minor CHD were 26.1 and 49.8 per 10000 live infants, respectively, in surveyed areas. Poisson regression analysis indicated that, compared with singleton infants, the prevalence rate ratio of CHD was higher in twin and multi-fetal infants (PRR:3.1, 95% CI:1.6, 6.1). Using southern Shaanxi as a reference, the PRR of CHD were lower in northern (PRR:0.4, 95% CI:0.3, 0.6) and central Shaanxi province (PRR:0.5, 95% CI:0.4, 0.7). PRR was higher in mothers over 30 years of age than in those under 25 years (PRR:1.6, 95% CI:1.0, 2.5), and in mothers with ≥3 parity than that in mothers with only one parity (PRR:2.2, 95% CI:1.2, 4.2). The risk for CHD among live infants was positively associated with family history of CHD (PRR: 9.8, 95% CI: 5.3, 18.1). Additionally, CHD was less common in the floating population than the permanent population (PRR: 0.6, 95% CI: 0.4, 0.9).

CONCLUSION

The CHD among live infants seemed to be a serious health problem in Shaanxi province as well as in Northwestern China. Our research have important policy implications for recommendations on CHD intervention in Northwest China.

Fetal cardiology: changing the definition of critical heart disease in the newborn

Infants born with congenital heart disease (CHD) may require emergent treatment in the newborn period. These infants are likely to benefit the most from a prenatal diagnosis, which allows for optimal perinatal planning. Several cardiac centers have created guidelines for the management of these high-risk patients with CHD. This paper will review and compare several prenatal CHD classification systems with a particular focus on the most critical forms of CHD in the fetus and newborn. A contemporary definition of critical CHD is one which requires urgent intervention in the first 24 h of life to prevent death. Such cardiac interventions may be not only life saving for the infant but also decrease subsequent morbidity. Critical CHD cases may require delivery at specialized centers that can provide perinatal, obstetric, cardiology and cardiothoracic surgery care. Fetuses diagnosed in mid-gestation require detailed fetal diagnostics and serial monitoring during the prenatal period, in order to assess for ongoing changes and identify progression to a more severe cardiac status. Critical CHD may progress in utero and there is still much to be learned about how to best predict those who will require urgent neonatal interventions. Despite improved therapeutic capabilities, newborns with critical CHD continue to have significant morbidity and mortality due to compromise that begins in the delivery room. Fetal echocardiography is the best way to predict the need for specialized care at birth to improve outcome. Once the diagnosis is made of critical CHD, delivery at the proper time and in appropriate institution with specific care protocols should be initiated. More work needs to be done to better delineate the risk factors for progression of critical CHD and to determine which newborns will require specialized care. The most frequently described forms of critical CHD requiring immediate intervention include hypoplastic left heart syndrome with intact or severely restricted atrial septum, obstructed total anomalous pulmonary venous return and transposition of the great arteries with restrictive atrial septum.

Second trimester cardiac diagnosis: screening standards and outcomes

Second trimester screening for congenital heart defects occurs during the routine 18-20 weeks' anomaly scan in many countries. Most congenital heart defects can be prenatally detected by experts in foetal echocardiography working in tertiary centres with high-risk pregnancies. Many studies, however, have shown that detection rates obtained by experts are not reproducible in the low-risk peripheral practices where most of the foetal screening takes place. As the majority of foetuses with congenital heart defects are born to mothers with no identifiable risk factors, it is important that widespread screening of the low-risk population occurs. To facilitate this, standard protocols have been introduced in several countries, but they are not universal and have differing sensitivities depending on the screening views advocated and the area studied. Initially, only performing the four-chamber view (basic scan) was advocated. By adding the outflow tract views (extended scan), three-vessel, and laterality views, the sensitivity of the examination can be significantly increased. Unfortunately, the sensitivity of these extended protocols still does not meet that obtainable in experienced hands, reflecting the additional skill required to obtain these extended views. Thus, close links are required between the tertiary centres and the screening centres to teach and maintain the skills required to obtain and interpret the required views, and to support the sonographer's commitment. Furthermore, an audit system is required to trace false-positive and -negative cases so that targeted interventions can be planned. This is important, as a missed case of prenatal congenital heart defect is potentially a missed opportunity to reduce postnatal morbidity and mortality.

Prenatal diagnosis of nonsyndromic congenital heart defects

OBJECTIVES

Congenital heart defects (CHDs) occur in nearly 1% of live births. We sought to assess factors associated with prenatal CHD diagnosis in the National Birth Defects Prevention Study (NBDPS).

METHODS

We analyzed data from mothers with CHD-affected pregnancies from 1998 to 2005. Prenatal CHD diagnosis was defined as affirmative responses to questions about abnormal prenatal ultrasounds and fetal echocardiography obtained during a structured telephone interview.

RESULTS

Fifteen percent (1097/7299) of women with CHD-affected pregnancies (excluding recognized syndromes and single-gene disorders) reported receiving a prenatal CHD diagnosis. Prenatal CHD diagnosis was positively associated with advanced maternal age, family history of CHD, type 1 or type 2 diabetes, twin or higher-order gestation, CHD complexity, and presence of extracardiac defects. Prenatal CHD diagnosis was inversely associated with maternal Hispanic race/ethnicity, prepregnancy overweight or obesity, and preexisting hypertension. Prenatal CHD diagnosis varied by time to NBDPS interview and NBDPS study site.

CONCLUSIONS

Further work is warranted to identify reasons for the observed variability in maternal reports of prenatal CHD diagnosis and the extent to which differences in health literacy or health system factors such as access to specialized prenatal care and fetal echocardiography may account for such variability.

Pregnancy outcomes and relative risk factors among Chinese women with congenital heart disease

OBJECTIVE

To summarize pregnancy outcomes among a cohort of Chinese women with congenital heart disease (CHD) and to identify predictive risk factors for maternal, fetal, and neonatal complications.

METHODS

A retrospective analysis of 529 women with CHD who gave birth at the Shanghai Obstetrical Cardiology Intensive Care Center, Shanghai, China, between January 1, 1993, and September 30, 2010. Maternal, fetal, and neonatal complications were evaluated for these women.

RESULTS

Maternal cardiac complications were reported in 33 (6.2%) of the women, whereas fetal and neonatal complications were reported in 145 (27.4%). The factors found to be significantly predictive for maternal cardiac complications were cardiac events before pregnancy (odds ratio [OR] 36.811), New York Heart Association functional class greater than II (OR 27.702), oxygen saturation below 90% (OR 7.506), and left ventricular obstruction (aorta stenosis) (OR 2.408). Factors significantly predictive for fetal and neonatal complications were New York Heart Association functional class greater than II (OR 20.12), oxygen saturation below 90% (OR 3.78), and pulmonary arterial hypertension (systolic pressure ≥ 50 mm Hg) (OR 3.42).

CONCLUSION

Identification of maternal, fetal, and neonatal complications among women with CHD may guide medical intervention and therefore reduce pregnancy-associated risk for these patients.

Parental needs among children with birth defects: defining a parent-to-parent support network

The objective of this study was to explore how a parent-to-parent support network could impact parents of a child with a structural birth defect by specifically looking at parents' continued needs, aspects influencing their participation in support networks, and their recommendations. Structural birth defects occur in approximately 3 % of all infants, representing a significant public health issue. For many reasons, parents are uniquely qualified to provide support to each other. Data were collected retrospectively through a qualitative approach of focus groups or one-on-one interviews. Thirty one parents of infants registered in the Utah Birth Defect Network participated in the study. Three themes emerged, "current sources and inconsistencies in parent-to-parent-support," "aspects that influence participation in parent-to-parent network," and "recommendations for a parent-to-parent program." Health care providers need to be aware of the services and inform parents about these options. A statewide parent-to-parent network integrated into all hospitals would be a valuable resource to facilitate sharing of issues related to caring for an infant or child with a birth defect.

Audit of 10 years of referrals for fetal echocardiography

OBJECTIVES

To evaluate trends over time, indications, diagnoses, noncardiac defects and outcome of fetuses referred for tertiary level echocardiography.

METHODS

Retrospective study of fetal echocardiograms performed between April 1999 and 2009.

RESULTS

Of the 623 fetuses included, 301 (48%) had cardiac pathology. Congenital heart defects (CHDs) were found in 243/301 (81%), mostly in the severe spectrum. Of the fetuses with CHDs, 26% (63/243) had chromosomal anomalies. The chromosomally normal fetuses with CHDs had a mortality rate of 43% (77/180) and 23% (41/180) had extra-cardiac anomalies. The termination of pregnancy (TOP) rate for all cardiac pathology was 24.9% (75/301) and for CHDs 29.6% (72/243). The TOP rates for CHDs diagnosed before 19 and 24 weeks gestation were 61% (28/46) and 44% (68/155), respectively. An increase in referrals followed the introduction of a national screening program, (nuchal translucency (NT) and routine structural ultrasound screening). The main referral indication was an increased NT (>95th percentile; 32% of cases). CHDs were found in 81/239 (34%) fetuses with an increased NT.

CONCLUSIONS

Referral indications for fetal echocardiography were appropriate (almost 50% had cardiac pathology). The mortality was high. Fetal outcome and TOP decisions correlated with CHD severity and presence of noncardiac defects. An increased NT is a strong marker for CHDs.

Congenital Heart Defects in Europe

Background—

This study determines the prevalence of Congenital Heart Defects (CHD), diagnosed prenatally or in infancy, and fetal and perinatal mortality associated with CHD in Europe.

Methods and Results—

Data were extracted from the European Surveillance of Congenital Anomalies central database for 29 population-based congenital anomaly registries in 16 European countries covering 3.3 million births during the period 2000 to 2005. CHD cases (n=26 598) comprised live births, fetal deaths from 20 weeks gestation, and terminations of pregnancy for fetal anomaly (TOPFA). The average total prevalence of CHD was 8.0 per 1000 births, and live birth prevalence was 7.2 per 1000 births, varying between countries. The total prevalence of nonchromosomal CHD was 7.0 per 1000 births, of which 3.6% were perinatal deaths, 20% prenatally diagnosed, and 5.6% TOPFA. Severe nonchromosomal CHD (ie, excluding ventricular septal defects, atrial septal defects, and pulmonary valve stenosis) occurred in 2.0 per 1000 births, of which 8.1% were perinatal deaths, 40% were prenatally diagnosed, and 14% were TOPFA (TOPFA range between countries 0% to 32%). Live-born CHD associated with Down syndrome occurred in 0.5 per 1000 births, with >4-fold variation between countries.

Conclusion—

Annually in the European Union, we estimate 36 000 children are live born with CHD and 3000 who are diagnosed with CHD die as a TOFPA, late fetal death, or early neonatal death. Investing in primary prevention and pathogenetic research is essential to reduce this burden, as well as continuing to improve cardiac services from in utero to adulthood.

Changing mortality in congenital heart disease

OBJECTIVES

This study sought to characterize temporal trends in all-cause mortality in patients with congenital heart disease (CHD).

BACKGROUND

Historically, most deaths in patients with CHD occurred in early childhood. Notable advances have since been achieved that may impact on mortality trends.

METHODS

We conducted a population-based cohort study of patients with CHD in Quebec, Canada, from July 1987 to June 2005. A total of 8,561 deaths occurred in 71,686 patients with CHD followed for 982,363 patient-years.

RESULTS

The proportion of infant and childhood deaths markedly declined from 1987 to 2005, with a reduction in mortality that exceeded that of the general population. Distribution of age at death transitioned from a bimodal to unimodal, albeit skewed, pattern, more closely approximating the general population. Overall, mortality decreased by 31% (mortality rate ratio: 0.69, 95% confidence interval [CI]: 0.61 to 0.79) in the last (2002 to 2005) relative to the first (1987 to 1990) period of observation. Mortality rates decreased in all age groups below 65 years, with the largest reduction in infants (mortality rate ratio: 0.23, 95% CI: 0.12 to 0.47). In adults 18 to 64 years, the mortality reduction (mortality rate ratio: 0.84, 95% CI: 0.73 to 0.97) paralleled the general population. Gains in survival were mostly driven by reduced mortality in severe forms of CHD, particularly in children (mortality rate ratio: 0.33, 95% CI: 0.19 to 0.60), and were consistent across most subtypes.

CONCLUSIONS

Deaths in CHD have shifted away from infants and towards adults, with a steady increase in age at death and decreasing mortality.