Congenital heart disease and extracardiac anomalies: associations and indications for fetal echocardiography

Cardiac Axis in Early Gestation and Congenital Heart Disease

Congenital heart defects represent the most common structural anomalies observed in the fetal population, and they are often associated with significant morbidity and mortality. The fetal cardiac axis, which indicates the orientation of the heart in relation to the chest wall, is formed by the angle between the anteroposterior axis of the chest and the interventricular septum of the heart. Studies conducted during the first trimester have demonstrated promising outcomes with respect to the applicability of cardiac axis measurement in fetuses with congenital heart defects as well as fetuses with extracardiac and chromosomal anomalies, which may result in improved health outcomes and reduced healthcare costs. The main aim of this review article was to highlight the cardiac axis as a reliable and powerful marker for the detection of congenital heart defects during early gestation, including defects that would otherwise remain undetectable through the conventional four-chamber view.

Fetal echocardiography in a low-income setting: relying on local Maternal-fetal medicine experts for detection of fetal cardiac anomalies

OBJECTIVE

To describe the experience of performing fetal echocardiography (FE) to detect fetal cardiac anomalies prenatally in an Ethiopian setting.

METHODS

A cross-sectional study was conducted at St Paul's Hospital Millennium Medical College (Addis Ababa, Ethiopia), from October 1, 2019 to September 30, 2020. Data for FE cases (on a risk-factor indication basis) performed at 22-24 weeks at the hospital during the study period were collected prospectively and analyzed using SPSSS version 23. Simple descriptive statistics were used to analyze the data. Results were presented as percentages and frequencies.

RESULTS

A total of 142 women who had FE were analyzed in this study. Fetal structural defect in other systems and maternal diabetes mellitus were the commonest indications for FE, seen in 48.2% (67/142) and 25.7% (36/142) of the participants, respectively. There were 5 cases (3.5%) of fetal cardiac anomalies among which were hypoplastic left heart syndrome, pulmonary stenosis, and cardiac tumor.

CONCLUSION

The prevalence of fetal cardiac anomalies in this study was found to be 3.5%. Fetal structural defects and maternal diabetes mellitus were the commonest indications for FE which is consistent with findings from previous similar studies.

Care of the Fetus With Congenital Cardiovascular Disease: From Diagnosis to Delivery

BACKGROUND

The majority of congenital cardiovascular disease including structural cardiac defects, abnormalities in cardiac function, and rhythm disturbances can be identified prenatally using screening obstetrical ultrasound with referral for fetal echocardiogram when indicated.

METHODS

Diagnosis of congenital heart disease in the fetus should prompt assessment for extracardiac abnormalities and associated genetic abnormalities once maternal consent is obtained. Pediatric cardiologists, in conjunction with maternal-fetal medicine, neonatology, and cardiothoracic surgery subspecialists, should counsel families about the details of the congenital heart defect as well as prenatal and postnatal management.

RESULTS

Prenatal diagnosis often leads to increased maternal depression and anxiety; however, it decreases morbidity and mortality for many congenital heart defects by allowing clinicians the opportunity to optimize prenatal care and plan delivery based on the specific lesion. Changes in prenatal care can include more frequent assessments through the remainder of the pregnancy, maternal medication administration, or, in selected cases, in utero cardiac catheter intervention or surgical procedures to optimize postnatal outcomes. Delivery planning may include changing the location, timing or mode of delivery to ensure that the neonate is delivered in the most appropriate hospital setting with the required level of hospital staff for immediate postnatal stabilization.

CONCLUSIONS

Based on the specific congenital heart defect, prenatal echocardiogram assessment in late gestation can often aid in predicting the severity of postnatal instability and guide the medical or interventional level of care needed for immediate postnatal intervention to optimize the transition to postnatal circulation.

Counseling for fetal heart disease-current standards and best practice

Congenital heart disease (CHD) is the most common cause of major congenital anomalies affecting newborns. Prenatal detection of CHD has been improving continuously during the last two decades due to technical advances and thus optimized fetal cardiac imaging. Besides the in-utero diagnosis of CHD effective parental counseling is an integral part of any Fetal Cardiology Program. However, studies on the most effective techniques are scarce, as well as data on empirical assessment of counseling and its effectiveness. In this review article, we summarize current guidelines from different international associations and societies. We provide an updated literature overview evaluating current standards of counseling with regard to parental needs. This includes ethical aspects, counseling for univentricular disease and in-utero cardiac interventions. We discuss our method to assess counseling success for fetal heart defects by exploring different analytical dimensions that may be considered helpful in order to improve efficacy. Finally, we present a proposal of how to optimize a setting for counseling based on the current literature and our own data. In summary, parental counseling for fetal heart disease is complex and multidimensional. Significant expertise in fetal cardiology and physiology, potential progression of CHD, postnatal treatment strategies and knowledge of long-term sequelae is necessary. A structured approach, together with continuous improvement of communicative skills, may lead to more effective counseling for parents following a diagnosis of CHD in the fetus.

Investigation of echocardiographic characteristics and predictors for persistent defects of patent foramen ovale or patent ductus arteriosus in Chinese newborns

Background

Persistent patent foramen ovale (PFO) and patent ductus arteriosus (PDA) increase the adult risk of cryptogenic embolic stroke and chronic pulmonary hypertension. To understand the characteristics of PFO and PDA in newborns, we investigated the spontaneous closure rate and derived the determinants for residual defects.

Methods

We utilized the database of congenital heart disease (CHD) in Xiamen ChangGung Memorial Hospital from 2015 to 2017 and allocated 2523 eligible newborns into four groups according to PDA, PFO, both or neither at birth. A total of 574, 1229, 202 and 518 newborns were assigned into the group of PFO and PDA, PFO alone, PDA alone and non-PFO/non-PDA, respectively. Regular echocardiographic follow-ups at baseline, 6, 12 and 24 months after birth were performed for evaluating the spontaneous closure rate in the subjects. Regression analysis was carried out to study the risk factors of residual congenital defects.

Results

Newborns with PFO alone had the youngest birth age and lowest birth weight among the four groups. About one in four PDA-alone newborns had concomitant small ASD, i.e., <5 mm in diameter. Echocardiographic study showed that 71.3% and 30.8% of CHD newborns had PFO and PDA, respectively, compared to less than 10% of them having ASD or VSD. However, more than 95% of newborns with PFO or PDA closed spontaneously at 6 months, in contrast to about 30% of newborns with ASD or VSD had persistent existence of the intracardiac defects. Complex CHD significantly linked to persistent PFO or PDA at 6 and 12 months, with an adjusted hazard ratio of 9.03 (95% CI 1.97–41.46) and 12.11 (95% CI 2.11–69.72), respectively.

Conclusions

Chinese newborns with PFO or PDA expressed differences in characteristics and concomitant congenital defects. Additionally, persistent PFO or PDA is strongly associated with complex CHD and requires long-term regular monitoring for future associated complications.

The evolution of fetal echocardiography before and during COVID-19

The World Health Organization declared the novel coronavirus, or COVID-19, a pandemic in March 2020. Given the severity of COVID-19, appropriate use criteria have been implemented for fetal echocardiography. Screening low risk pregnancies for critical congenital heart disease has typically been a shared responsibility by pediatric cardiologists, obstetricians, and maternal fetal medicine (MFM). Currently, many of the fetal echocardiograms for low risk pregnancies for critical congenital heart disease have been deferred or cancelled with the emphasis on suspected abnormalities by MFMs and obstetricians. In this review, we discuss the literature that has been the basis of screening of low risk pregnancies by pediatric cardiologists. A new approach to more widespread usage of fetal tele-echocardiography may play a large part during COVID-19 and may continue after the pandemic.

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Appropriate use criteria for fetal echocardiography have been implemented during the COVID-19 pandemic.

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Pediatric cardiologists have deferred fetal echo for low risk pregnancies, emphasizing those with suspected abnormalities.

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Current fetal echo guidelines highlight maternal, familial, and fetal risk factors, and the associated incidence of CHD.

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Fetal tele-echocardiography and telehealth consultation may enhance the ability to provide care during and beyond COVID-19.

Efficacy of fetal cardiac axis evaluation in the first trimester as a screening tool for congenital heart defect or aneuploidy

Objective

To prove the efficacy of determining the abnormal fetal cardiac axis for screening congenital heart defects (CHDs) and predicting fetal aneuploidy at 11.0 to 13.6 weeks of pregnancy.

Methods

This retrospective study was performed at a single high-risk pregnancy center. The fetal cardiac axis was evaluated between 11.0 and 13.6 weeks of gestation in 142 fetuses. The cardiac axis in a 4-chamber view was measured as the angle between the line tracing the long axis of the heart and the line bisecting the thorax in the anteroposterior direction. A CHD was confirmed based on the second- to third-trimester fetal status or postnatal imaging. Aneuploidy was diagnosed using chorionic villus sampling, amniocentesis, or genetic testing after birth. Fisher's exact test was performed to assess the association between the fetal cardiac axis and the abnormal fetal status. A 2-way contingence table analysis was performed to confirm the efficacy of the fetal cardiac axis as a screening tool.

Results

Among the 142 fetuses, 10 had a CHD while 17 had aneuploidy. The abnormal fetal cardiac axis was significantly associated with CHDs (P=0.013) and aneuploidy (P=0.010). None of the fetuses with CHDs or aneuploidy had an isolated abnormal cardiac axis alone without other sonographic findings. The sensitivity of the fetal cardiac axis was 50.0% for CHDs and 41.2% for aneuploidy.

Conclusion

The fetal cardiac axis can be an additional helpful tool for prenatal screening of CHDs and aneuploidy in the first trimester.

Ultrasound Measurements of Frontal Horns and the Cavum Septi Pellucidi in Healthy Fetuses in the Second and Third Trimesters of Pregnancy

OBJECTIVES

To assess the visualization rate and size of the frontal horns (FHs) and cavum septi pellucidi (CSP) in healthy fetuses throughout pregnancy.

METHODS

After Institutional Review Board approval, 522 consecutive uncomplicated singleton pregnancies between 15 and 39 gestational weeks were enrolled in the study. Ultrasound measurements of the anterior horn width (AHW), center from the horn distance (CFHD), distance from the FHs to the CSP, and CSP width were retrospectively performed using axial transventricular or transcerebellar planes. Available maternal body mass indices were recorded.

RESULTS

At least 1 FH was seen in 78% of the cases. The mean AHW decreased over the second trimester and plateaued in the third trimester. The CFHD plateaued in the second trimester and increased in the third trimester. Downside FHs were generally larger than upside FHs. More FHs were measured in transventricular (69%) than transcerebellar (31%) planes. Frontal horns were seen with high, low, and no confidence in 57%, 21%, and 22% of cases, respectively. No-confidence rates were 17% in the second trimester and 42% in the third trimester. The CSP was not visualized in 4% of cases; 15 of 19 cases of a nonvisualized CSP were scanned between 18 and 37 weeks. Mean body mass indices ± SDs were 27.6 ± 6.7 kg/m² for the patients in cases of a visualized CSP and 32.4 ± 9.1 kg/m² for the patients in cases of a nonvisualized CSP.

CONCLUSIONS

Normative data for the fetal FH and CSP width were established. Frontal horns are more frequently seen on transventricular views and are difficult to confidently assess in the late third trimester. This study challenges previously reported data that the CSP is seen in 100% of cases from 18 to 37 weeks.

Genetic Basis for Congenital Heart Disease: Revisited: A Scientific Statement From the American Heart Association

This review provides an updated summary of the state of our knowledge of the genetic contributions to the pathogenesis of congenital heart disease. Since 2007, when the initial American Heart Association scientific statement on the genetic basis of congenital heart disease was published, new genomic techniques have become widely available that have dramatically changed our understanding of the causes of congenital heart disease and, clinically, have allowed more accurate definition of the pathogeneses of congenital heart disease in patients of all ages and even prenatally. Information is presented on new molecular testing techniques and their application to congenital heart disease, both isolated and associated with other congenital anomalies or syndromes. Recent advances in the understanding of copy number variants, syndromes, RASopathies, and heterotaxy/ciliopathies are provided. Insights into new research with congenital heart disease models, including genetically manipulated animals such as mice, chicks, and zebrafish, as well as human induced pluripotent stem cell-based approaches are provided to allow an understanding of how future research breakthroughs for congenital heart disease are likely to happen. It is anticipated that this review will provide a large range of health care-related personnel, including pediatric cardiologists, pediatricians, adult cardiologists, thoracic surgeons, obstetricians, geneticists, genetic counselors, and other related clinicians, timely information on the genetic aspects of congenital heart disease. The objective is to provide a comprehensive basis for interdisciplinary care for those with congenital heart disease.

Birth Location of Infants with Critical Congenital Heart Disease in California

The American Academy of Pediatrics classifies neonatal intensive care units (NICUs) from level I to IV based on the acuity of care each unit can provide. Birth in a higher level center is associated with lower morbidity and mortality in high-risk populations. Congenital heart disease accounts for 25-50% of infant mortality related to birth defects in the U.S., but recent data are lacking on where infants with critical congenital heart disease (CCHD) are born. We used a linked dataset from the Office of Statewide Health Planning and Development to access ICD-9 diagnosis codes for all infants born in California from 2008 to 2012. We compared infants with CCHD to the general population, identified where infants with CCHD were born based on NICU level of care, and predicted level IV birth among infants with CCHD using logistic regression techniques. From 2008 to 2012, 6325 infants with CCHD were born in California, with 23.7% of infants with CCHD born at a level IV NICU compared to 8.4% of the general population. Level IV birth for infants with CCHD was associated with lower gestational age, higher maternal age and education, the presence of other congenital anomalies, and the diagnosis of a single ventricle lesion. More infants with CCHD are born in a level IV NICU compared to the general population. Future studies are needed to determine if birth in a lower level of care center impacts outcomes for infants with CCHD.

Fetal Macrosomia, Polyhydramnios and Cardiac Anomalies may be Helpful to Predict Poor Outcome in Neonate – Case Report of a Possible Fetal Rasopathy with Sonographic and Neonatal Findings and Genetic Evaluation

This is a case report about very rare findings in 2nd half of pregnancy (after normal 1 trimester scan ) at 18th week of gestation fetal macrosomia was detected unrelated to maternal diabetes, and acceleration fetal growth later on with unusual cardiac abnormalities (fetal cardiomegaly, cardiomyopathy, partial abnormal venous connection ). Progressive features of congestive heart failure with polyhydramnios in a fetus with estimated 5500 g predicted a poor outcome and severe neonatal condition, which was presented and discussed with the parents to be. Casearean section was performed at 33rd weeks of gestation due to maternal dyscomfort, severe legs edema and her tachypnoe. Baby boy was delivered with birth weight of 5050g, Apgar 4 with mutiple tumors. Conservative care was introduced and neonated died on the 3rd day. Differential diagnosis was discussed with special attention to Costello syndrome however without proved by genetic make-up from neonatal blood.

Clinical aspects of prenatally detected congenital heart malformations and the yield of chromosomal microarray analysis

OBJECTIVE

The yield of chromosomal microarray analysis (CMA) for prenatally detected congenital heart defects (CHD) is 6.6% to 19.2%. We evaluated the yield of CMA in cases of prenatally detected CHD in regard to specific clinical characteristics.

METHODS

Data from 192 cases of CHD including type, clinical and familial background, workup performed during the pregnancy, and pregnancy outcomes were collected.

RESULTS

Fetal echocardiography was performed in all cases; 61.4% of CHD were suspected by ultrasound. There was a positive family history (FH) in 15.7%. Abnormal nuchal translucency or umbilical cord anomalies were detected in 1.7% and 5.9%, respectively, and 55.1% were isolated cases. In 11 of 96 cases in which genetic testing was performed, karyotype and CMA were abnormal (11.5%). The detection rate of CMA (performed in 72 cases) was 9.7%. The yield of CMA was similar in simple cases, isolated cases, and cases with a positive FH. CMA was abnormal in 7.3% of ventricular septal defect cases.

CONCLUSION

Most cases of prenatally detected CHD had no additional extra-cardiac, sonographic findings suggesting increased risk for CHD. The yield of CMA testing was significant in all clinical scenarios including simple heart malformations, isolated cases, and cases with a positive FH. © 2016 John Wiley & Sons, Ltd.

A Review of Fetal Circulation and the Segmental Approach in Fetal Echocardiography

The incidence of congenital heart disease is generally estimated at 8 in 1000 live births. Fifty percent of these neonates will have “minor” defects—easily corrected with some intervention. The remainder will account for 30% of perinatal deaths and nearly 50% of lethal malformations in childhood. The purpose of this review is to outline essential guidelines for a thorough fetal echocardiogram and how it differs from the fetal cardiac imaging included as part of an obstetric sonographic examination. Specific values for both the anatomic and blood flow velocity measurements recommended are typically related to gestational age and method of acquisition. Multiple references exist in the literature that define these values.

Identification of fetal cardiac anatomy and hemodynamics: a novel enhanced screening protocol

Background

Prenatal cardiac screening is of great importance as it contributes to appropriate neonatal management and helps parents to make a decision regarding their pregnancy. The aim of our study was to evaluate the efficiency of a newly proposed screening protocol in the detection of fetal congenital heart disease (CHD).

Methods

This was a prospective study. A total of 52 cases of confirmed CHD fetuses and 248 cases of randomly selected normal fetuses were included in the study. Two sonographers with similar experience performed the cardiac screenings under two different protocols independently. The conventional protocol (Protocol A) paid greater attention to the four-chamber view and the outflow tract views. A 6-month training program was provided to sonographers performing scans under the new protocol (Protocol B), which emphasized systematically evaluating fetal cardiac anatomy and hemodynamics. Color Doppler was mandatory and some ultrasonic signs for special cardiac anomalies were also introduced into this protocol.

Results

Protocol B detected more cardiac anomalies than did Protocol A (96.2 % vs. 61.5 %, P < 0.01). Specifically, Protocol B was superior to Protocol A in detecting cardiac malpositions, abnormal systemic and pulmonary venous connection, right aortic arch, transposition of the great arteries, and congenital corrected transposition of the great arteries. By visualizing flow disturbance and retrograde flow with color Doppler, Protocol B was better than Protocol A in screening valvular associated malformations, such as pulmonary atresia, pulmonary stenosis, tricuspid dysplasia, etc. For the normal fetuses, Protocol B was better than Protocol A in reducing the false-positive detection of septal defects.

Conclusions

The current study introduces an enhanced protocol for fetal cardiac screening, under which the obstetric screening sonographers systematically identify fetal cardiac anatomy and hemodynamics. A short-term training program makes it possible for the screening sonographers to become familiar with the new protocol, and its value has been confirmed due to improvements made in screening efficiency.

Electronic supplementary material

The online version of this article (doi:10.1186/s12884-016-0933-9) contains supplementary material, which is available to authorized users.

Extracardiac malformations: associations and importance: consequences for perinatal management of foetal cardiac patients

Foetal echocardiography has become an established subspecialty in paediatric cardiology. The skills to perform detailed assessment of foetal cardiac anomalies in a tiny, moving foetus surrounded by sometimes challenging layers of maternal tissue are not easy to obtain, and require prolonged periods of specific training and supervised scanning in expert centres. The goal of this overview is to discuss the importance of the awareness of the fact that expert examination of the foetal heart and in-depth knowledge of newborn surgical interventions are only a part of the picture; many cardiac abnormal foetuses do not just have an isolated cardiac defect. The extracardiac malformations, when present, play a major role in determining the treatment and prognosis. The challenge of providing optimal prenatal care to the pregnant woman, who remains the primary patient at least until the umbilical cord is cut, carrying a foetus with a cardiac malformation is to organise rapid, effective, and complete evaluation of all possible foetal anomalies in a multidisciplinary team approach, followed by clear and honest non-directive counselling on all possible options. Only then, with the maximum involvement of the parents, decisions on perinatal management can be taken by the team. Controversies do exist in view of various obstetric, paediatric, and other specialists on how to best organise this multidisciplinary care programme. In this paper, we provide a practical, logical, and efficient path of care for the pregnant woman suspected to carry a foetus with a heart defect.

Diagnosis and treatment of fetal cardiac disease: a scientific statement from the American Heart Association

BACKGROUND

The goal of this statement is to review available literature and to put forth a scientific statement on the current practice of fetal cardiac medicine, including the diagnosis and management of fetal cardiovascular disease.

METHODS AND RESULTS

A writing group appointed by the American Heart Association reviewed the available literature pertaining to topics relevant to fetal cardiac medicine, including the diagnosis of congenital heart disease and arrhythmias, assessment of cardiac function and the cardiovascular system, and available treatment options. The American College of Cardiology/American Heart Association classification of recommendations and level of evidence for practice guidelines were applied to the current practice of fetal cardiac medicine. Recommendations relating to the specifics of fetal diagnosis, including the timing of referral for study, indications for referral, and experience suggested for performance and interpretation of studies, are presented. The components of a fetal echocardiogram are described in detail, including descriptions of the assessment of cardiac anatomy, cardiac function, and rhythm. Complementary modalities for fetal cardiac assessment are reviewed, including the use of advanced ultrasound techniques, fetal magnetic resonance imaging, and fetal magnetocardiography and electrocardiography for rhythm assessment. Models for parental counseling and a discussion of parental stress and depression assessments are reviewed. Available fetal therapies, including medical management for arrhythmias or heart failure and closed or open intervention for diseases affecting the cardiovascular system such as twin-twin transfusion syndrome, lung masses, and vascular tumors, are highlighted. Catheter-based intervention strategies to prevent the progression of disease in utero are also discussed. Recommendations for delivery planning strategies for fetuses with congenital heart disease including models based on classification of disease severity and delivery room treatment will be highlighted. Outcome assessment is reviewed to show the benefit of prenatal diagnosis and management as they affect outcome for babies with congenital heart disease.

CONCLUSIONS

Fetal cardiac medicine has evolved considerably over the past 2 decades, predominantly in response to advances in imaging technology and innovations in therapies. The diagnosis of cardiac disease in the fetus is mostly made with ultrasound; however, new technologies, including 3- and 4-dimensional echocardiography, magnetic resonance imaging, and fetal electrocardiography and magnetocardiography, are available. Medical and interventional treatments for select diseases and strategies for delivery room care enable stabilization of high-risk fetuses and contribute to improved outcomes. This statement highlights what is currently known and recommended on the basis of evidence and experience in the rapidly advancing and highly specialized field of fetal cardiac care.

Utility of fetal echocardiography after normal cardiac imaging findings on detailed fetal anatomic ultrasonography

OBJECTIVE

The purpose of this study was to assess the utility of fetal echocardiography (FE) after normal fetal cardiac imaging findings during detailed fetal anatomic ultrasonography (FAU).

METHODS

We conducted a retrospective cohort review of obstetric ultrasonographic studies from November 2001 through July 2005. We identified women with a singleton gestation with increased risk for congenital heart disease who received FAU performed by a maternal-fetal medicine specialist at 16 to 20 weeks' gestation with subsequent FE. These records were compared with newborn outcomes.

RESULTS

Of 789 pregnancies that had FAU and FE, 481 had satisfactory cardiac imaging. Of those, only 1 fetus had abnormal FE findings. After delivery, 4 of the 480 neonates with normal FAU and FE findings had a diagnosis of a heart defect.

CONCLUSIONS

Fetal echocardiography does not substantially increase the detection rate of major cardiac anomalies after normal findings on detailed FAU performed by a maternal-fetal medicine specialist.

Pregnancy: Maternal and Fetal Heart Disease

Cardiac disorders complicate less than 1% of all pregnancies. Physiologic changes in pregnancy may mimic heart disease. In order to differentiate these adaptations from pathologic conditions, an in-depth knowledge of cardiovascular physiology is mandatory. A comprehensive history, physical examination, electrocardiogram, chest radiograph, and echocardiogram are sufficient in most cases to confirm the diagnosis. Care of women with cardiac disease begins with preconception counseling. Severe lesions should be taken care of prior to contemplating pregnancy. Management principles for pregnant women are similar to those for the non-pregnant state. A team approach comprised of a maternal fetal medicine specialist, cardiologist, neonatologist, and anesthesiologist is essential to assure optimal outcome for both the mother and the fetus. Although fetal heart disease complicates only a small percentage of pregnancies, congenital heart disease causes more neonatal morbidity and mortality than any other congenital malformation. Unfortunately, screening approaches for fetal heart disease continue to miss a large percentage of cases. This weakness in fetal screening has important clinical implications, because the prenatal detection and diagnosis of congenital heart disease may improve the outcome for many of these fetal patients. In fact, simply the detection of major heart disease prenatally can improve neonatal outcome by avoiding discharge to home of neonates with ductal-dependent congenital heart disease. Fortunately, recent advances in screening techniques, an increased ability to change the prenatal natural history of many forms of fetal heart disease, and an increasing recognition of the importance of a multidisciplinary, team approach to the management of pregnancies complicated with fetal heart disease, together promise to improve the outcome of the fetus with congenital heart disease.

The influence of prenatal diagnosis on postnatal outcome in patients with structural congenital heart disease

Examination of the fetal heart has become an established part of mid-trimester anomaly scanning. Along side this has emerged the ability to diagnose congenital heart disease in the fetus with accuracy. Despite this, the development of screening programmes to look for fetal cardiac disease has only been partially successful. Furthermore, when detected, there seems to be little survival advantage associated with prenatal diagnosis. Demonstrating such an advantage is complicated by the nature of fetal cardiac disease, which tends to be severe and is often associated with extra-cardiac abnormalities. More selective studies, mostly involving small numbers of cases, are now beginning to demonstrate both improved survival and reduced morbidity in prenatally diagnosed infants presenting to cardiac intensive care units compared to those with a postnatal diagnosis.

Should all pregnant diabetic women undergo a fetal echocardiography? A cost-effectiveness analysis comparing four screening strategies

OBJECTIVE

To determine if a policy of universal fetal echocardiography for all pregnant diabetic women is cost-effective as a screening tool for congenital heart defects.

STUDY DESIGN

Using a decision-analysis model, we compared the cost-effectiveness of four screening strategies: (1) none--no ultrasound is performed; (2) selective fetal echocardiography after abnormal detailed anatomic survey; (3) fetal echocardiography for only high hemoglobin A1C, and (4) universal fetal echocardiography for all diabetics. The sensitivity and specificity for each strategy were derived by literature search. The analysis was from a societal perspective using a willingness-to-pay threshold (50,000 dollars) and a theoretic cohort of 40,000 pregnant diabetics. Costs included costs of tests and the costs of complications and of raising a child with a cardiac defect. Outcomes were reported as cost per quality-adjusted life years (QALY) gained for each congenital heart defect prevented by each strategy and the number of congenital heart defects detected. One-way, multiway and probabilistic sensitivity analyses were performed.

RESULTS

Compared with the other strategies, selective fetal echocardiography after abnormal detailed anatomic survey costs less per QALY gained for cardiac defect screening. Although universal fetal echocardiography was associated with a higher detection rate for cardiac defects, it was more costly. The sensitivity analyses revealed a robust model over a wide range of values.

CONCLUSION

Under the baseline assumptions, selective fetal echocardiography after an abnormal detailed anatomic survey is more cost-effective compared with universal fetal echocardiography as a screening strategy for cardiac defects in pregnant diabetics.

Postmortem findings and clinicopathological correlation in congenital diaphragmatic hernia

Congenital diaphragmatic hernia (CDH) is a severe life-threatening disease, with an incidence of 3 per 10,000 births, that can occur as an isolated defect or in combination with other congenital anomalies. We reviewed the clinical and autopsy reports of 39 subjects with CDH that were autopsied between 1988 and 2001 to determine whether autopsy had an additional value in the detection of malformations in patients with CDH. We compared the clinical data (including echographic results in some patients) concerning congenital anomalies with the autopsy results. Before autopsy, 6 structural cardiac defects, 3 anomalies of the urogenital system, and 3 anomalies of the digestive tract were observed in 10 patients (clinical and echographic results). However, with postmortem examination, only 4 structural cardiac defects were confirmed, 2 cases showed another cardiac anomaly, and 7 new cardiac defects were found. In the urogenital system, 1 anomaly was confirmed, 1 was not confirmed, and 1 showed another malformation. In addition, in 7 patients new urogenital malformations were found after autopsy. In the digestive tract, all 3 malformations were confirmed, but we found 3 new malformations after postmortem examination. All clinically established dysmorphic features and anomalies of the skeletal system and central nervous system were confirmed by autopsy, and no additional malformations were found. We concluded that postmortem examination has an important additional role in the detection of structural cardiac defects and malformations of the urogenital system and digestive tract in children with CDH.

Screening for congenital heart disease

Congenital heart disease has the characteristics of a disease that is suited to screening, and the four-chamber view is an effective screening tool with a sensitivity of 40% to 50%. The use of multiple cardiac views can increase the pre-natal detection to 60% to 80%. Given that most infants with congenital heart disease are born to low-risk women, routine screening is warranted. Early pre-natal diagnosis provides an opportunity to exclude associated extracardiac and chromosomal abnormalities, discuss pregnancy options, adjust obstetric management, prepare parents for delivery of an affected baby, and plan delivery in a tertiary care center. Despite the widespread use of ultrasonography, only 15% to 30% of infants with congenital heart disease are identified prenatally. There is a need to do better.

Routine fetal cardiac screening: what are we doing and what should we do?

In many countries, ultrasound examination is used in the second trimester to look for congenital malformations as part of routine prenatal care. While tertiary centres scanning high-risk pregnancies have reported a high degree of accuracy in the detection of congenital heart disease, many studies have shown that cardiac abnormalities are commonly overlooked during routine obstetric evaluation and there still remains a huge variation between centres. The majority of babies with congenital heart disease are born to mothers with no identifiable high-risk factors and so will not be detected unless there is widespread screening of the low-risk population. It is feasible to achieve widespread screening for fetal congenital heart disease in low-risk groups, but this does need commitment and effort from those performing the scans and those teaching them how to examine the heart. Staff performing routine obstetric ultrasound scans should learn a simple technique for examining the fetal heart and to use this in all patients. Links to a tertiary centre can provide support for checking scans of concern as well as for providing training and for obtaining feedback. In addition, an audit system needs to be established in each centre to trace false-positive and false-negative cases as well as to confirm true positives and true negatives.

Prenatal diagnosis of congenital heart disease: the beginning

Congenital heart disease (CHD) is the most common life-threatening defect in the first month of life. Its incidence is 8 per 1000 live newborns. Fetal echocardiography is used to screen, diagnose, monitor, and treat congenital heart defects and rhythm abnormalities. Early and improved diagnosis can hopefully impact morbidity, mortality, and emotional well-being of the family. Over the past three decades, fetal echocardiography has evolved into a discipline whereby the diagnosis of congenital heart disease has improved survival and in utero interventions. Continued research, improved technology, and broadened expertise will hopefully allow the health care team to provide better outcomes.

Maternal psychological impact of fetal echocardiography

The maternal psychological impact of fetal echocardiography may be deleterious in the face of newly diagnosed congenital heart disease. This questionnaire-based study prospectively examined the psychological impact of both normal and abnormal fetal echocardiography. Normal fetal echocardiography decreased maternal anxiety, increased happiness, and increased the closeness women felt toward their unborn children. In contrast, when fetal echocardiography detected congenital heart disease, maternal anxiety typically increased, and mothers commonly felt less happy about being pregnant. However, among women who had recently delivered infants with congenital heart disease, those who had had fetal echocardiography during the pregnancy felt less responsible for their infants' defects and tended to have improved their relationships with the infants' fathers after the prenatal diagnosis of congenital heart disease. Further study of the psychological and medical impact of fetal echocardiography will be necessary to define and optimize the clinical value of this powerful diagnostic tool.

Correlation between fetal cardiac diagnosis by obstetric and pediatric cardiologist sonographers and comparison with postnatal findings

OBJECTIVE

To assess the level of agreement between obstetric and pediatric cardiologist sonographers' diagnosis of fetuses with suspected congenital heart disease and to compare this with the final postnatal diagnosis.

DESIGN

We retrospectively reviewed the notes of 1037 patients undergoing fetal echocardiography over a 5-year period (1995-99) at the principal tertiary referral center for fetal cardiology in New South Wales, Australia. The median gestational age at presentation was 21 weeks (range 17-38) with 49% of the scans performed at < 21 weeks and a further 17% performed at 21-24 weeks. The accuracy of the fetal cardiac diagnosis was validated by neonatal cardiac investigation or autopsy.

RESULTS

A total of 249 cases of congenital heart disease were identified antenatally during this 5-year period with the majority (84%) referred because of suspicion of a cardiac malformation during an obstetric scan. Of the 268 fetuses with congenital heart disease suspected by obstetric sonographers, 209 had confirmed cardiac defects. Complete correlation between obstetric sonographers' and pediatric cardiologists' prenatal cardiac findings was achieved in 62% of cases. There were major differences involving the atrioventricular morphology in 18% of cases and the outflow tract anatomy in 20%. Complete agreement between prenatal and postnatal diagnosis in fetuses with complex congenital heart disease was achieved in 59% of cases for obstetric sonography (17% false positive; 41% false negative) and 95% for fetal echocardiography by pediatric cardiologists (2% false positive; 5% false negative).

CONCLUSIONS

Improved accuracy in diagnosis can be achieved through a pediatric cardiologist with special skills in fetal echocardiography working collaboratively with obstetric sonographers to optimize the details of diagnosis. This may influence management and counseling.

Fetal cardiology

A systematic approach to examination of the fetal heart will enhance the detection of structural cardiac abnormalities and will enable an accurate diagnosis of congenital heart disease to be made. Once an abnormality has been detected appropriate counselling must be provided and adequate support given to the parents. Associated extracardiac abnormalities should be sought for, and plans for the remainder of pregnancy, delivery and postnatal management should be made using a team approach. In cases resulting in termination of pregnancy, permission for autopsy should be sought to confirm the ultrasound diagnosis. Although in-utero therapy is available for some forms of fetal arrhythmia and a few limited cases of structural heart disease, this should be conducted in tertiary centres.

Three-dimensional (3-D) ultrasonography for obtaining the four and five-chamber view: comparison with cross-sectional (2-D) fetal sonographic screening

OBJECTIVES

To assess the ability of Doppler-gated 3-D fetal echocardiography to reconstruct and display specific cardiac structures routinely visualized during antenatal ultrasound in a population at low risk for cardiac anomalies. To determine whether any advantage is offered by 3-D sonographic cardiac examination over conventional sonographic fetal screening techniques.

DESIGN

After routine two-dimensional sonographic examination, 3-D cardiac data were collected prospectively in 30 fetuses with gestational ages between 19 and 23 weeks from a low risk patient population. Basic echocardiographic key views were derived from 3-D data and selected for reconstruction and analysis. Four- and five-chamber views were rated and only those views judged to be well visualized were considered as positive results.

RESULTS

The four- and five-chamber views were well visualized in all but one fetus using conventional 2-D imaging. Gated 3-D volume data sets enabled visualization of these structures in only 19 of 30 fetuses but provided additional structural depth and allowed a dynamic 3-D perspective of valvar morphology and ventricular wall motion. The right ventricular outflow tract was available from the 3-D volumes in 16 subjects.

CONCLUSIONS

Considering the versatility of gated 3-D fetal cardiac imaging we believe that it may soon become an important component of fetal screening thus helping to retrieve standard cardiac cross sections when 2-D imaging is limited by lack of sonographer experience or sonographic windows. Diagnostically acceptable echocardiographic views were obtained more consistently with 2-D ultrasound than with 3-D volume data.

Spectrum of congenital heart defects and extracardiac malformations associated with chromosomal abnormalities: results of a seven year necropsy study

OBJECTIVE

To analyse the spectrum of congenital heart malformations, the frequency of extracardiac malformations, and the proportion of chromosome aberrations among fetuses sent for necropsy.

MATERIAL

Necropsies were performed on 815 fetuses-448 induced abortions (55%), 220 spontaneous abortions (27%), and 147 stillbirths (18%)-during a seven year period (1991-97) in the department of pathology of the Charité Medical Centre in Berlin. A congenital heart defect was identified in 129 cases (16%). For all 129 fetuses, karyotyping and an ultrasound examination had been performed.

RESULTS

Congenital heart defects were present in 22% of induced abortions (99 cases), 9% of spontaneous abortions (20 cases), and 7% of stillbirths (10 cases). The heart malformations were classified into 13 categories. A fetus with more than one defect was included only in the category of the most serious defect. The malformations in order of frequency were: ventricular septal defect (VSD) (28%), atrioventricular septal defect (AVSD) (16%), hypoplastic left heart (HLH) (16%), double outlet right ventricle (DORV) (12%), coarctation of the aorta (CoA) (6%), transposition of the great arteries (TGA) (4%), aortic valve stenosis (AoVS) (4%), tetralogy of Fallot (TOF) (3%), truncus arteriosus communis (TAC) (3%), pulmonary valve stenosis/pulmonary valve atresia (PaVS/PaVA) (3%), tricuspid atresia (TA) (3%), single ventricle (SV) (1.5%), and atrial septal defect (ASD) (0.5%). The most common congenital heart defects were VSD, AVSD, HLH, and DORV, which made up 72% of all the cases. In 11 cases the heart defect was isolated (no other cardiovascular or extracardiac malformations present), 85 cases (66%) were associated with additional cardiac malformations, 85 cases (66%) were associated with extracardiac malformations, and chromosome anomalies were detected in 43 cases (33%).

CONCLUSIONS

Fetal congenital heart malformations are common. These defects are often associated with other cardiovascular and extracardiac malformations, as well as with chromosome anomalies. Complex heart defects such as AVSD, HLH, and DORV are frequent in fetuses, as they often lead to spontaneous abortion or stillbirth or, after prenatal diagnosis, to deliberate termination of pregnancy.

Advances in echocardiographic diagnostic modalities for the pediatrician

Two-dimensional Doppler echocardiography has become the primary diagnostic tool in the assessment of infants and children with congenital and acquired heart disease. Over the past 10 years, specialized echocardiographic techniques have also become critical components in the evaluation and treatment of these patients. Using fetal echocardiography enables us to image the heart early in gestation and have begun to understand those lesions that can develop and progress in utero. Transesophageal echocardiography has allowed you to image the patient with congenital heart disease during repair in the operating room and in the cardiac catheterization laboratory so that adequacy of the repair can be assess and any residual lesions addressed immediately. Both of these specialized techniques are discussed in detail, with a brief overview at the three-dimensional future of echocardiography in the pediatric patient.

Ultrasound evaluation of the fetal heart: is it possible?

Ultrasound evaluation of the fetal heart can be performed. Knowledge of the embryology, anatomy, and function of the heart have led us to understand the pathophysiology of congenital heart disease. In this review we discuss the indications as well as some basic principles of fetal echocardiography.

Obtaining the four-chamber view to diagnose fetal cardiac anomalies

Four-chamber view screening of the fetal heart was greeted with significant optimism in the mid-1980s. This screening technique was initially expected to detect most congenital heart disease in utero; however, recent studies demonstrate a 4% to 40% sensitivity of four-chamber view screening. It is therefore probable that the dream of antepartum diagnosis of most congenital heart disease in utero will remain unfulfilled. This is particularly true with increasing funding constraints for health care provision imposed by both the federal government and third-party payors.

Prognosis following prenatal diagnosis of heart malformations

Our objective was to document the prognosis of cases with fetal heart malformations (FHM). Forty-two fetuses assessed both in a regional fetal medicine and paediatric cardiology unit were classified prenatally into isolated FHM or those associated with extra-cardiac structural or karyotypic anomalies (ECA) and this classification was not changed subsequently (analogous to an intention to treat analysis). The end points studied included chromosomal abnormality, pregnancy outcome and follow-up at one year of age. FHM were isolated in 16 (38%) and associated with ECA in 26 (62%) of cases. The karyotypic abnormality rate was 8/42 (19%) overall and 8/26 (31%) in ECA cases. The pregnancy outcome included termination of pregnancy in 19 (45%), intrauterine death of two (5%) and live birth in 21 (50%). 12/16 (75%) of isolated FHM cases were live born compared with 9/26 (35%) of ECA cases (P < 0.03). Of the isolated FHM live born babies, 8/12 (67%) were alive at the end of the first year and seven of these were growing normally and did not require cardiac medication. However, a considerable proportion of their first year was spent in hospital (median 8%, interquartile range 5-10). Only one of nine ECA live born cases was alive but with poor growth and dependence on cardiac drugs at one year. These data confirm previous findings in prenatal diagnosis series that the prognosis for FHM is worse than that reported in studies of congenital heart disease at birth and is strongly dependent upon the presence of ECA. In their absence, outcome is better than previously published. Counselling must take place only after full fetal medicine assessment and should be based upon prenatal data.

Prenatal diagnosis of congenital heart disease

Owing to the widely different levels of experience of examiners, there is a large discrepancy in study results of second trimester ultrasound screening for fetal malformations, which is a result of varying levels of obstetric scanning expertise prevalent at the reporting centre. This holds particularly true for the prenatal diagnosis of congenital heart disease where detection rates ranging from 0 per cent to 60 per cent are being reported. On the other hand, congenital heart disease affects about 4-8 per 1000 live births and is a leading cause of infant mortality, whereas prenatal diagnosis could possibly prevent death and long-term morbidity in some of these neonates. Various screening concepts for more effective detection of congenital heart diseases are analysed in this article, including the more recent technique of early echocardiography between 13 and 15 weeks of gestation. High-risk groups are defined and the group of fetuses with increased thickness of nuchal translucency seems to be of particular interest.

Transabdominal chorionic villus sampling in the second and third trimesters of high-risk pregnancies

Late chorionic villus sampling (placental biopsy) under ultrasound guidance was carried out in 800 (80 per cent) cases in the second trimester and 200 (20 per cent) cases in the third trimester of pregnancy. Out of 1000 placental biopsies, 250 (25 per cent) were performed because of suspicious ultrasonographic findings. Colour Doppler was used to investigate the uteroplacental and fetal vessels in 300 (30 per cent) pregnancies before and after late chorionic villus sampling (CVS). In the same group, mean serum alpha-fetoprotein (AFP) levels increased after sampling in 20 (6.7 per cent) patients. In 20 patients (2 per cent), complications between sampling and delivery were found. A placental haematoma measuring 0.5-1 ml was seen at the sampling site in 4 (0.4 per cent) patients in the second trimester of pregnancy and in 3 (0.3 per cent) in the third trimester. Two (0.2 per cent) demonstrated fever, but there were no instances of chorioamnionitis. There were only three (0.3 per cent) spontaneous abortions 4-6 weeks after late CVS. However, there was no correlation between AFP elevation, placental haematoma, Doppler measurements, and spontaneous abortion. Cytogenetic findings were obtained in 990 (99 per cent) of 1000 placental samplings. We found 60 (6.0 per cent) chromosomal abnormalities. In the group with suspicious ultrasonic findings (250 cases), we found significant oligohydramnios in 125 (50 per cent) and significant polyhydramnios in 60 (24 per cent), and 45 (18 per cent) had chromosomal abnormalities. Among the 60 patients with chromosomal abnormalities, ultrasonographic findings in 10 (16.7 per cent) were detected after the 20th week of pregnancy. There were no significant differences in mean pulsatility index (PI) in the uteroplacental and fetal vessels before and after late CVS. Preliminary data from five trisomic fetuses (three trisomy 21 and two trisomy 18) showed abnormally increased umbilical PI and abnormally decreased middle cerebral artery PI.

Prenatal diagnosis of congenital heart disease; prospects and problems

Routine fetal echocardiography has been submitted as an antenatal screening test for congenital heart disease despite a wide range of efficacy reported. Hence, evaluation of the variable results of prenatal ultrasound screening programs was pursued. As the studies appeared to have a heterogeneous design, the originally reported figures have been corrected for one plausible prevalence of cardiovascular anomalies. Clinical setting (general hospitals vs. teaching hospitals), case ascertainment (retrospective vs. prospective; follow-up on (suspected) cases only vs. routine follow-up) and length of follow-up (< 1 year vs. a longer period) all have similar effects on the reported yield of cases and sensitivity of the proposed screening test. Notably, a relatively low yield of cases causes a seemingly high sensitivity, whereas a higher yield of cases causes a seemingly low sensitivity. Additional factors of study design, e.g. case definition, diagnostic procedures and appliances used, were usually not described in detail, yet may also have affected the results. Evaluating diagnostic tests apparently demands a rigorous study design to overcome biased results. Furthermore, no sufficient evidence could be found meriting current routine prenatal screening for congenital heart disease.

Combining humerus and femur length for improved ultrasonographic identification of pregnancies at increased risk for trisomy 21

OBJECTIVE

Our purpose was to evaluate the value of the combination of femur and humerus length measurements in ultrasonographic screening for trisomy 21.

STUDY DESIGN

Direct necropsy measurements were analyzed on 703 midgestational fetuses (641 normal, 62 with trisomy 21). The (leg+arm length)/foot length ratio was found to be significantly shortened for fetuses with trisomy 21. On the basis of necropsy data 576 midgestational pregnancies were evaluated ultrasonographically for (femur+humerus length)/foot length ratio to identify fetuses at increased risk for trisomy 21.

RESULTS

An ultrasonographic (femur+humerus length)/foot length ratio < or = 1.75 gave a 15.3 odds ratio risk for trisomy 21 in our high-risk population and correctly identified 53% of fetuses with trisomy 21, with a false-positive rate of 7%. In addition, the use of this ratio eliminates the need for gestational age-corrected nomograms and complicated calculations in ultrasonographic screening.

CONCLUSION

The (femur+humerus length)/foot length ratio may be an additional effective ultrasonographic marker for identification of fetuses at increased risk for trisomy 21.

In utero pulmonary artery and aortic growth and potential for progression of pulmonary outflow tract obstruction in tetralogy of Fallot

OBJECTIVES

This study was designed to define patterns of pulmonary artery and aortic growth in fetuses with tetralogy of Fallot and to determine the potential for in utero progression of right ventricular outflow tract obstruction.

BACKGROUND

Despite an abundance of reports documenting the prenatal diagnosis of tetralogy of Fallot, there is little information about its course in utero.

METHODS

Pulmonary artery and ascending aortic diameters were measured from prenatal and postnatal echocardiograms of 16 fetuses with tetralogy of Fallot, initially studied at 23.6 +/- 6.0 (mean +/- SD) weeks of gestation. Fetuses were classified retrospectively as having mild and severe tetralogy of Fallot according to whether the pulmonary artery circulation was (severe, n = 5) or was not (mild, n = 11) ductus arteriosus dependent at birth.

RESULTS

Initial main pulmonary artery diameter was small for gestational age in 9 fetuses, large in 2 and normal in 5 compared with data from 57 gestational age-adjusted normal fetal studies; it was significantly smaller in the group with severe tetralogy of Fallot (p = 0.05). The initial main pulmonary artery/aortic diameter ratio was also smaller for the group with severe tetralogy of Fallot (0.50 +/- 0.15 vs. 0.73 +/- 0.14 in the group with mild tetralogy of Fallot, p = 0.01). Initial aortic and branch pulmonary artery diameters tended to be normal or near normal for age. In eight fetuses serially studied, main and branch pulmonary artery growth was normal or reduced during prenatal follow-up. Pulmonary artery growth was most reduced in two fetuses in the group with severe tetralogy of Fallot, resulting in pulmonary artery hypoplasia at birth. Two fetuses with valvular pulmonary atresia at birth had previously shown anterograde pulmonary outflow in midgestation, suggesting progression of pulmonary outflow obstruction.

CONCLUSIONS

The postnatal spectrum of pulmonary artery size in tetralogy of Fallot can be attributed to variable patterns of growth in utero. Main pulmonary artery size, main pulmonary artery/aortic diameter ratio and pattern of pulmonary artery growth may be predictive of the severity of postnatal pulmonary outflow obstruction. Pulmonary atresia can develop in utero in some fetuses with tetralogy of Fallot.

Basic technique of fetal echocardiography

The fetal heart is the organ system most commonly affected with congenital disease. Though risk factors exist for congenital heart disease (eg, family history, toxin exposure, maternal illness, abnormal karyotype, and other fetal anomalies), the fetal heart is most often examined as part of a routine evaluation of the fetal anatomy in the fetus with no identifiable risk factors. The importance of a systematic, complete assessment of the cardiac axis cannot be overemphasized. All aspects of sonography (ie, real time, M-mode, pulsed, and color Doppler) can provide unique and integral information in evaluating the fetal heart and thorax.

Prenatal diagnosis of recurrent Meckel syndrome

We report a rare case of Meckel-Gruber syndrome in a woman who had three affected offsprings in the past with similar condition. Ante-natal ultrasonographic diagnosis and management are presented.

Outcome of prenatally detected cardiac malformations

Reliable, prenatal detection of congenital heart disease has become possible over the past decade with the evolution of fetal echocardiography. We have documented the outcome of 170 cardiac defects diagnosed prenatally since 1984. Of 170 cases, 55 (32%) had major extracardiac malformations and 45 (28%) chromosomal abnormalities (16 had both). Elective termination was chosen in 77 (45%) pregnancies. Of 93 continuing pregnancies 15 were stillborn and 43 died postnatally (48% of these fetuses and infants had extracardiac or chromosomal anomalies, or both). Thirty-five patients survive at 1 to 80 months (mean 36). Aneuploidy or extracardiac defects are present in 20% of survivors. Nonimmune hydrops secondary to cardiac failure was present in 7 continuing pregnancies and none of these patients survived. The prognosis of prenatally diagnosed cardiac lesions is negatively influenced by the presence of cardiac failure, aneuploidy or extracardiac malformations, or a combination of these. Optimal counseling and management requires the identification of these conditions when present.