Echocardiography in early pregnancy: review of literature

HDlive Flow Silhouette with spatiotemporal image correlation for assessment of fetal cardiac structures at 12 to 14 + 6 weeks of gestation

OBJECTIVES

To assess fetal cardiac structures using HDlive Flow Silhouette with spatiotemporal image correlation (STIC) at 12 to 14 + 6 weeks of gestation, and verify the feasibility of obtaining five cardiac views in the late first and early second trimesters of pregnancy. The fetal cardiac shape and the aspect of the descending aorta were also evaluated.

METHODS

Eighty normal fetuses at 12 to 14 + 6 weeks of gestation were studied using trans-abdominal HDlive Flow Silhouette with STIC to assess the feasibility of five fetal cardiac views (frontal, spatial three-vessel, panoramic, posterior, and right lateral views). Target structures in each cardiac view were evaluated. 'Good' was assigned when all structures were noted, 'Fair' when only one structure was missed, and 'Poor' when two and more structures could not be detected. Frequencies of an elongated heart and those of a tortuous descending aorta were counted.

RESULTS

Forty-nine fetuses were effectively included in the analysis. Success rates of 'Good' and 'Fair' were significantly higher with spatial three-vessel (p<0.01) and panoramic views (p<0.05). Frequencies of "Elongated heart", "Elongated left ventricle", and "Spherical heart" were 12.2, 6.2, and 81.6%, respectively. Frequencies of "Tortuous descending aorta" and "Straight descending aorta" were 12.2 and 87.8%, respectively.

CONCLUSIONS

The feasibility of obtaining fetal five cardiac views using HDlive Flow Silhouette with STIC is good, and this technique provides useful information for evaluating fetal cardiac structures in the late first and early second trimesters of pregnancy.

Fetal development of the human trapezius and sternocleidomastoid muscles

At present, there is no photographic evidence of splitting of the trapezius and sternocleidomastoid muscles (SCMs), which share a common anlage that extends caudally toward the limb bud in the embryo at a length of 9 mm. Therefore, the aim of the present study was to identify which structures divide the caudal end of the common anlage at the first sign of splitting into two muscles. In 11 mm-long specimens, the SCM and trapezius muscles were identified as a single mesenchymal condensation. In 15 and 18 mm-long specimens, the SCM and trapezius muscles were separated and extended posteriorly and lymphatic tissues appeared in a primitive lateral cervical space surrounded by the SCM (anterior). In 21 mm-long specimens, the lymphatic vessels were dilated and the accompanying afferents were forming connections with the subcutaneous tissue through a space between the SCM and trapezius muscles. In 27 mm-long specimens, cutaneous lymphatic vessels were evident and had entered the deep tissue between the SCM and trapezius muscles. Vascular dilation may be viewed as a result of less mechanical stress or pressure after muscle splitting.

ACR Appropriateness Criteria® Nuchal Translucency Evaluation at 11 to 14 Weeks of Gestation

A fetus with an increased nuchal translucency at 11 to 14 weeks gestation is at risk for aneuploidy, genetic syndromes, structural anomalies, and intrauterine fetal demise in both single and twin gestations. In addition to referral to genetics for counseling and consideration of diagnostic genetic testing, a detailed anatomic survey and fetal echocardiogram are indicated in the second trimester to screen for congenital malformations and major heart defects. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

First-Trimester Ultrasound

Since the 1980s, development of high-resolution transvaginal ultrasound transducers has significantly improved ultrasound evaluation at earlier gestational ages. Although many indications exist for first-trimester ultrasound in pregnancy, more emphasis has been placed on assessment of fetal anatomy recently. In turn, congenital diagnoses can also be made earlier in pregnancy, raising the question of whether anatomic assessment in the first trimester is one of choice or obligation. Combining transvaginal and transabdominal approach yields the highest detection rate overall. Some studies have shown that more than half of all anomalies and almost all severe anomalies can be detected on early scans.

Importance of Follow-Up and Early Detailed Evaluation in Early Onset Growth Restricted Fetuses

Early onset fetal growth restriction (EO-FGR) is associated with significant feto-maternal complications, therefore efforts should be made to identify the causes and the potential outcome of the pregnancy. Some of the pitfalls in first-trimester imaging of the fetal anomalies are related to the inadequacy of the examination, because of the fetal position and limited clarity in relation to the size of the structures being examined. In this paper we present a case where careful ultrasound scan follow-up and the use of both approaches transabdominal and transvaginal were useful to complete a detailed structural evaluation as part of the diagnosis, management and prognosis of a fetuses diagnosed with EO-FGR in the first trimester and a triploidy with atypical ultrasound features.

Prenatal and postnatal echocardiography in NT fetuses with normal karyotype

INTRODUCTION

Targeted fetus echocardiography at midpregnancy can detect major defects in major cardiovascular organs. The present study aimed to evaluate prenatal and postnatal echocardiography in fetuses with increased nuchal translucency (NT) with normal karyotype.

METHODS

In this retrospective study, data on the screening of fetuses in pregnant women between 2014 and 2015 were evaluated. The fetuses at the gestational age were 14-11 weeks, and NT ≥ 95 percentile (or 3 mm). For all fetuses with increased NT, follow-up anomaly scan was performed at 18-22 weeks of pregnancy, while fetal echocardiography was performed at weeks 16-19 of pregnancy. The results were analyzed by Statistical Package for the Social Sciences (version 22) and the level of significance was less than 0.05.

RESULTS

A total of 26.27% of the fetuses were diagnosed with prenatal heart defects and confirmed after birth. The strongest relationship was observed between increased NT and the diagnosis of prenatal heart defects at 2.5-5.3 mm. The increased NT was higher in younger mothers. Moreover, increased NT was higher in mothers with less body mass index.

CONCLUSION

By measuring NT in the 11-13 weeks of pregnancy and considering the risk factors, it is possible to evaluate the probability of cardiac abnormalities in the fetus and perform the necessary diagnostic evaluations for high-risk cases.

Advances in ultrasound imaging for congenital malformations during early gestation

BACKGROUND

With refinement in ultrasound technology, detection of fetal structural abnormalities has improved and there have been detailed reports of the natural history and expected outcomes for many anomalies. The ability to either reassure a high-risk woman with normal intrauterine images or offer comprehensive counseling and offer options in cases of strongly suspected lethal or major malformations has shifted prenatal diagnoses to the earliest possible gestational age.

METHODS

When indicated, scans in early gestation are valuable in accurate gestational dating. Stricter sonographic criteria for early nonviability guard against unnecessary intervention. Most birth defects are without known risk factors, and detection of certain malformations is possible in the late first trimester.

RESULTS

The best time for a standard complete fetal and placental scan is 18 to 20 weeks. In addition, certain soft anatomic markers provide clues to chromosomal aneuploidy risk. Maternal obesity and multifetal pregnancies are now more common and further limit early gestation visibility.

CONCLUSION

Other advanced imaging techniques during early gestation in select cases of suspected malformations include fetal echocardiography and magnetic resonance imaging.

Imaging the first trimester heart: ultrasound correlation with morphology

First trimester sonography is a widely used technique to examine the foetus early in pregnancy. The desire to recognise complex anatomy already in early developmental stages stresses the need for a thorough knowledge of basic developmental processes as well as recognition of cardiac compartments based on their morphology. In this paper, we describe the possibilities and limitations of sonographic assessment of the foetal heart between 10 and 14 weeks of gestation and correlate this to morphology. Examples of the most commonly detected congenital anomalies are atrioventricular septal defects, transposition of the great arteries, and hypoplastic left heart, which are shown in this paper.

Should the first trimester ultrasound include anatomy survey?

First trimester scanning has become routine since the introduction of nuchal translucency screening. While most scans have included dating and gross anatomical structures, recent reports have shown that with improvement of ultrasound technology, especially high-frequency transvaginal transducers, detailed analysis of the early fetal anatomy is now possible. Studies included in this manuscript demonstrate the ability to now being able to identify many fetal malformations including some very subtle ones. The literature presented has carefully conducted many prospective studies presenting timelines that show optimal periods to review the anatomical structures by a given gestational age especially noting when these anatomical structures are not optimally seen.

Echocardiography in Early Pregnancy

Within the last decade, two significant events have contributed to the increasing interest in early fetal echocardiography. First, the introduction of high frequency vaginal ultrasound probes allows detailed visualization of cardiac structures at early stage of gestation, making early detection of fetal malformations possible. Second, the close relationship observed between some first trimester sonographic and Doppler markers and congenital heart defects allows an early identification of a high-risk group at 11 to 14 weeks of gestation. In this context, from the early 1990s, many authors have examined the potential role of the transvaginal approach to obtain earlier diagnosis of fetal cardiac malformations. Further studies have appeared in the literature showing that early transvaginal echocardiography in experienced hand is a fairly sensitive investigative tool. Although some malformations are detected as early as 11 weeks’ gestation, the optimal gestational age to perform the early scan is at least 13 weeks’ gestation. Transvaginal ultrasound is the preferred approach, although most of the authors agree that results can be improved if transabdominal ultrasound is also incorporated. The further application of color Doppler enhances visualization. The sensitivity and specificity of early fetal echocardiography for the detection of heart anomalies is acceptable compared to the ones obtained by mid-gestational echocardiography, showing a slight reduction in detection rates and an increase in false positive and negative rates. The cardiac anomalies detected at this early stage of pregnancy are mainly defects involving the four-chamber view, indicating that defects solely affecting the outflow tracts are difficult to diagnose in the first trimester of pregnancy. Heart defects diagnosed early in pregnancy tend to be more complex than those detected later, with a higher incidence of associated structural malformations, chromosomal abnormalities and spontaneous abortions. The neonate follow-up or postmortem examination in case of termination of pregnancy (TOP) is essential to assess the actual role of early fetal echocardiography. At present, early fetal echocardiography is a promising technique, which can be of considerable value for patients at high-risk. This technique is, however, currently limited to a few specialized centers.

The aim of this review is to explore the possibilities of examining the fetal heart at this early stage of pregnancy. This article also present our experience in the first multicenter trial in early fetal echocardiography performed in Spain. In accordance with other studies, this experience stresses the usefulness of early echocardiography when performed by expert operators on fetus specifically at risk for cardiac defects. Our review of these additional 48 cases contributes to the expanding literature on the ability of transvaginal ultrasonography to detect fetal heart defects in early pregnancy.

How to cite this article

Gabriel CC, Rodriguez PP. Echocardiography in Early Pregnancy. Donald School J Ultrasound Obstet Gynecol 2013;7(2):168-181.

Diagnosis of tetralogy of Fallot and its variants in the late first and early second trimester: details of initial assessment and comparison with later fetal diagnosis

OBJECTIVE

We sought to evaluate the completeness of echocardiographic diagnosis of fetal tetralogy of Fallot (fTOF) at 12-17 weeks gestation, and compare assessment and clinical outcomes to diagnoses made at >17 weeks gestation.

METHODS

We identified all fTOF diagnoses made in our experience from 2003 to 2008. Referral indication, anatomic detail by echocardiography and pregnancy outcomes were compared between fetuses diagnosed at ≤ 17 weeks (Group I) and >17 weeks gestation (Group II). A 10-point scoring tool was applied retrospectively to the echocardiograms at initial diagnosis (1 point each was ascribed to visualization of right ventricular outflow obstruction, pulmonary valve, pulmonary arteries including dimensions, pulmonary arterial flow, systemic and pulmonary venous anatomy, atrioventricular valves, ductus arteriosus, ductus flow, aortic arch morphology, sidedness and flow).

RESULTS

There were 10 pregnancies in Group I (12-17 weeks) and 25 in Group II (mean gestation at diagnosis 23.5 ± 5.7). The most common reason for referral was extracardiac pathology in Group I (80%) and suspected fetal heart disease on obstetric ultrasound in Group II (64%). Transabdominal imaging was adequate in about half of Group I studies. Mean anatomic diagnosis score in Group I was 6.1(range 2.5-9) and Group II was 8.4 (range 6.5-10). Elective pregnancy termination occurred in 80% in Group I and 33% in Group II.

CONCLUSIONS

fTOF can be diagnosed in first and early second trimesters with detailed anatomic assessment possible in most. Referral indication and pregnancy outcome differ considerably between early and later prenatal diagnosis of fTOF.

Early fetal echocardiography and anomaly scan in fetuses with increased nuchal translucency

Nuchal translucency (NT) identified at the time of the 11-14 week scan has been established as one of the best tools for screening for Down syndrome. It has also proven to be of value in screening for other conditions such as cardiac defects and extra-cardiac structural abnormalities. In this article, we present data from our fetal medicine unit that highlight the importance of using NT measurement as a stratifying tool when referring for early scans. We propose that, whenever possible, in selected cases with increased NT, provision should be made for additional early scans at 14-18 weeks of gestation with a view to providing information on fetal structural integrity well ahead of the routine scheduled appointments. Early scans should incorporate detailed assessment of the fetal cardiac as well as extra-cardiac anatomy to diagnose or rule out major structural defects. This strategy will provide reassurance to a large number of prospective parents.

Defining the fetal cardiac axis between 11 + 0 and 14 + 6 weeks of gestation: experience with 100 consecutive pregnancies

OBJECTIVE

The purpose of this study was to establish normal fetal cardiac axis values during the first and early second trimesters of pregnancy.

METHODS

This was a prospective observational cohort study in which the fetal cardiac axis was assessed during ultrasound examinations in 100 consecutive fetuses between 11 + 0 and 14 + 6 weeks of gestation. Transabdominal, and, when indicated, transvaginal, approaches were used. Intraobserver and interobserver reproducibility were calculated.

RESULTS

The cardiac axis ranged from 34.5 to 56.8° (mean (SD) 47.6 ± 5.6°) in 94 fetuses with normal cardiac anatomy. The fetal cardiac axis tended to be significantly higher in fetuses at 11 + 0 to 11 + 6 weeks of gestation than in fetuses at 12 + 0 to 14 + 6 weeks of gestation. Congenital heart defects were found in six out of 100 fetuses, four of which had abnormal cardiac axis values at 11 + 0 to 14 + 6 weeks of gestation.

CONCLUSION

Cardiac axis measurement is possible in the first and early second trimesters of pregnancy. The assessment of cardiac axis at an early gestational age may help to identify pregnancies at high risk for congenital heart defects. Copyright

Implications of bidirectional flow in the great arteries at the 11-14-week scan

OBJECTIVE

To determine the implications of a bidirectional Doppler flow pattern detected in one or both of the fetal great arteries in the first trimester.

METHODS

Database records were reviewed for cases of bidirectional flow found on fetal echocardiography performed at less than 15 weeks of gestation between January 1999 and October 2006 inclusive. Bidirectional flow consisted of antegrade flow in systole and retrograde flow in diastole. Data including indication for fetal echocardiography, gestational age at diagnosis, the anatomical features, karyotype, nuchal translucency measurement and outcome were collected.

RESULTS

From almost 2500 scans, bidirectional flow was detected in a total of 15 fetuses. The abnormal flow pattern was confined to the aorta in four, to the pulmonary artery in four, and was present in both great arteries in a further seven fetuses. Eight of the 15 fetuses had regurgitation at one or both atrioventricular valves. Additional cardiac abnormalities were detected by ultrasound in eight cases. Of the 13 cases for which the karyotype was known, 12 were abnormal and five of these had trisomy 18. None of the fetuses survived. There were two intrauterine deaths and 13 terminations of pregnancy.

CONCLUSION

Bidirectional flow in one or both great arteries is an unusual finding at the first-trimester scan and must be distinguished from the retrograde flow occurring only in systole in duct-dependent heart defects. It carries a poor prognosis, which is a consequence of both the high chance of underlying chromosomal abnormality and the hemodynamic compromise associated with severe arterial valve regurgitation.

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.

Fetal echocardiography during routine first-trimester screening: a feasibility study in an unselected population

OBJECTIVE

To evaluate the feasibility of obtaining standard echocardiographic views of the fetal heart during routine first-trimester screening and construct reference ranges for cardiac biometry at 11 + 0 to 13 + 6 weeks of gestation.

METHODS

A cross-sectional study of 584 fetuses in an unselected population. Viable pregnancies with a crown-rump length (CRL) of 41-78 mm were included. Echocardiography was performed by a single obstetrician using a 5 to 7.5 MHz vaginal transducer. The course and outcome of pregnancies were recorded and information on the babies was obtained in all cases.

RESULTS

A completely satisfactory visualization of the fetal heart structures was possible in 58% (43%, 56% and 62% at 11, 12 and 13 weeks, respectively). Reference ranges were constructed from the measurements of cardiac ventricles, their outflow tracts, and cardiothoracic circumference ratio in relation to CRL.

CONCLUSION

Standard echocardiograhic views of the fetal heart can be obtained at 11 + 0 to 13 + 6 weeks of gestation using the transvaginal approach. New reference ranges were established for fetal cardiac biometry at 11 + 0 to 13 + 6 weeks of gestation.

Likelihood ratio for trisomy 21 in fetuses with tricuspid regurgitation at the 11 to 13 + 6-week scan

OBJECTIVE

To determine the likelihood ratio for trisomy 21 in fetuses with tricuspid regurgitation at the 11 to 13 + 6-week scan.

METHODS

Fetal echocardiography was carried out by specialist pediatric cardiologists in 742 singleton pregnancies at 11 to 13 + 6 weeks' gestation and pulsed wave Doppler was used to ascertain the presence or absence of tricuspid regurgitation. To avoid confusion with other adjacent signals, a strict definition of tricuspid regurgitation was used, in that it had to occupy at least half of systole and reach a velocity of over 80 cm/s. The fetal crown-rump length (CRL) and the nuchal translucency (NT) thickness were measured and the presence of any congenital heart abnormality noted. Follow-up of the pregnancy was carried out to determine the presence of chromosomal abnormalities. The likelihood ratio for trisomy 21 in fetuses with and without tricuspid regurgitation was determined.

RESULTS

The tricuspid valve was successfully examined in 718 (96.8%) cases. Tricuspid regurgitation was present in 39 (8.5%) of the 458 chromosomally normal fetuses, in 82 (65.1%) of the 126 with trisomy 21, in 44 (53.0%) of the 83 with trisomy 18 or 13, and in 11 (21.6%) of the 51 with other chromosomal defects. The prevalence of tricuspid regurgitation was also associated with fetal CRL, delta NT and the presence of cardiac defects. Logistic regression analysis, irrespective of cardiac defects, demonstrated that in the chromosomally normal fetuses significant independent prediction of the likelihood of tricuspid regurgitation was provided by fetal delta NT (odds ratio (OR), 1.26; 95% CI, 1.34-1.41; P < 0.0001), while in trisomy 21 fetuses prediction was provided by CRL (OR, 0.94; 95% CI, 0.89-0.99; P = 0.021). The likelihood ratio for trisomy 21 for tricuspid regurgitation was derived by dividing the likelihood in trisomy 21 by that in normal fetuses. In the chromosomally normal fetuses, the prevalence of tricuspid regurgitation in those with cardiac defects was 46.9% and 5.6% in those without cardiac defects, and the likelihood ratio of tricuspid regurgitation for cardiac defects was 8.4.

CONCLUSION

At 11 to 13 + 6 weeks' gestation, there is a high association between tricuspid regurgitation and trisomy 21, as well as other chromosomal defects. The prevalence of tricuspid regurgitation increases with fetal NT thickness and is substantially higher in those with, than those without, a cardiac defect.

First-trimester fetal heart block and increased nuchal translucency: an indication for early fetal echocardiography

Prevalence of congenital heart disease increases with nuchal translucency (NT) thickness. First-trimester fetal bradycardia may result from heart block associated with complex congenital heart disease. We report two cases detected in the first trimester of pregnancy, in which both fetuses showed an increased nuchal translucency and bradycardia. Fetal karyotype was normal in both fetuses. First-trimester fetal echocardiography was performed and, in both cases, complex congenital heart disease was diagnosed. We discuss the added role of fetal heart rate in first-trimester ultrasound screening, in fetuses with increased nuchal translucency and normal karyotype. We stress, as well, the importance of echocardiography performed in the first trimester as a potential tool for early diagnosis in selected cases.

Latest advances and topics in fetal echocardiography

PURPOSE OF REVIEW

Fetal diagnosis and the supporting specialties of perinatology, neonatology, and surgery have made rapid strides in the last decade. Numerous centers are focusing on this multifaceted niche area as the medical field realizes its vast promise and potential. The authors review some of the major advancements in thought and practice in the field of fetal echocardiography while attempting to give a less detailed overview for the less involved perinatologist.

RECENT FINDINGS

First trimester fetal echocardiography has been an area of recent interest as transducer technology improves. As a result, optimum timing of first and subsequent scans and the population profile they are to be applied to have become an issue that begs consensus. Three-dimensional and four-dimensional fetal echocardiography have also received a boost for the same reasons, and both are being studied for feasibility and accuracy. Fetal tissue Doppler and spectral Doppler imaging are potential areas for exploration; the early steps have been taken. Awareness of associated ultrasound markers, such as exaggerated nuchal translucency, as clues to the presence of congenital heart disease is important, even if controversial.

SUMMARY

The issue of missed prenatal diagnosis is disturbing, especially when it arises against a background of tremendous skill and technologic support. Strategies to minimize mistakes in this critical aspect need to be agreed on by the involved teams and put in place in a multidisciplinary manner if they are to have an important impact.

Genetic counseling throughout the life cycle

As the definition of genetic counseling continues to evolve, so does the application of genetic counseling services in all areas of medicine and throughout the human life cycle. While governmental policy, economics, ethics, and religion continue to influence society's views regarding the necessity of testing germ cells for mutations to prevent the birth of an affected child or predicting whether healthy adults will develop future life-threatening illness, patient autonomy in the choice of whether to know, or not know, one's genetic make-up remains a core principle of genetic counseling.

New dimensions and directions in fetal cardiology

PURPOSE OF REVIEW

The purpose of this review is to describe several of the most relevant and exciting recent advances in the field of fetal cardiology.

RECENT FINDINGS

First, the prenatal detection of congenital heart disease has improved, and continues to improve, with the increasingly widespread incorporation of the four-chamber view and outflow tracts into the routine screening fetal ultrasound evaluation. Second, increasingly sophisticated computer processing systems and improvements in imaging technology have enabled the development of automated three-dimensional ultrasound imaging systems that promise to revolutionize both the prenatal detection and diagnosis of congenital heart disease. Conventional two-dimensional imaging approaches may soon become obsolete. Third, there has been an increasing ability to intervene successfully prenatally not only for fetal arrhythmias and heart failure, but also for some forms of structural heart disease. In some cases of left or right ventricular outflow tract obstruction, early intervention during the second trimester may prevent the development of ventricular hypoplasia. Finally, several recent studies suggest that prenatal diagnosis may improve neonatal outcome for fetuses with congenital heart disease. The growing ability to intervene prenatally has the potential to improve neonatal outcome still further.

SUMMARY

These critical and exciting developments in fetal cardiology promise to increase fetal echocardiography's clinical impact dramatically during the years to come.