Factors influencing the prenatal detection of structural congenital heart diseases

High Heterogeneity in Prenatal Detection of Severe Congenital Heart Defects Among Physicians, Hospitals and Regions in Quebec

BACKGROUND

Prenatal detection rates (PDRs) of severe congenital heart defects (SCHDs) are often presented as regional and national aggregates, which might hide significant heterogeneity in PDRs among physicians, hospitals, and regions. The objective was to quantify the variability in the sensitivity of second-trimester ultrasound examination (U/S) to detect SCHDs, and to identify at which level this variability was the greatest.

METHODS

This was a retrospective observational cohort of all pregnancy-child dyads with SCHDs in Quebec between 2007 and 2015. We matched the clinical data from the hospitals with the administrative data from the health care system. The variability at each level was estimated using multilevel models by calculating intraclass correlation coefficients.

RESULTS

Of 1274 SCHD, 697 were diagnosed prenatally following a referral for a suspected cardiac anomaly on U/S, yielding a sensitivity of 54.7% (95% confidence interval [CI], 52.0%-57.4%). Significant heterogeneity was observed among physicians, hospitals, and regions with the greatest heterogeneity among physicians. The U/S sensitivities in the lowest quartile for physicians, hospitals, and regions were 27.4%, 29.0%, and 39.8%, and those in the highest quartile were 87.3%, 70.1%, and 62.9%, respectively. The mean difference of sensitivity between the lowest and highest quartiles was 59.9% (95% CI, 51.7-68.1) for physicians, and 41.1% (95% CI, 30.3-51.9) for hospitals. The intraclass correlation coefficients at the physician level indicated the greatest heterogeneity among physicians (intrahospital).

CONCLUSIONS

There was considerable heterogeneity in PDRs between physicians and hospitals. The driver of the heterogeneity seemed to be at the physician level, with higher interphysician variability. Any measures of improvement should be directed to the physician level.

Feasibility of neurosonography in CHD-fetuses and controls in a clinical tertiary setting

Objective

Ultrasonographic examination is the first-tier test to detect abnormal development of central nervous system (CNS). In optimal conditions, neurosonography can detect all important hallmarks of CNS development. It is, however, not known how the performance of this modality is in a routine setting. We aimed to evaluate the feasibility of neurosonography in a time-limited routine setting.

Study design

We have performed a prospective study in which we have included a group of pregnant women carrying a fetus with an isolated congenital heart defect (CHD), and a control group of fetuses without structural anomalies. We have performed basic neurosonography examination according to the guideline 'how to perform a basic screening examination of the CNS', published by the international society of ultrasound in obstetrics and gynecology in both groups. In all these examinations, 9 brain structures were scored in 3 different planes, by researchers that were blinded for group allocation. A sufficient neurosonogram was performed when 7 or more out of 9 CNS structures were clearly visible during the off-line scoring of the examination.

Results

A total of 574 neurosonographic examinations were performed in 151 fetuses, 90 in the CHD-group and 61 in the control group. A sufficient neurosonogram could be performed in 79% (234/294) of cases in a clinical setting (CHD cases) and in 90% (253/280) of control pregnancies. Higher maternal BMI (>30), maternal age, fetal cephalic position, fetal gender and placental position did not significantly influence neurosonography scores.

Conclusion

In clinical setting, basic fetal neurosonography can be sufficiently performed in the majority of cases. This was not significantly influenced by maternal or fetal factors. The optimal gestational age for neurosonography is between 22 and 34 weeks.

Postnatal diagnosis of congenital anomalies despite active systematic prenatal screening policies: a population-based registry study

BACKGROUND

Prenatal screening for congenital anomalies is an important component of maternity care, with continual advances in screening technology. However, few recent studies have investigated the overall effectiveness of a systematic policy of prenatal screening for congenital anomalies, such as in France where an ultrasound per trimester is recommended for all pregnant individuals.

OBJECTIVE

This study aimed to assess the proportion and the type of congenital anomalies that are not detected during pregnancy.

STUDY DESIGN

The study population included all singleton fetuses and newborns with congenital anomalies from the Paris Registry of Congenital Malformations (remaPAR) from 2001 to 2021. The registry includes all live births and stillbirths at ≥22 weeks of gestation and terminations of pregnancy for fetal anomaly at any gestational age with congenital anomalies diagnosed from the prenatal period until discharge home from hospital after birth. The prevalence of postnatally detected congenital anomalies was estimated overall and for 5-year intervals within the study period. We also reported the proportion of postnatal detection by subgroups of congenital anomalies according to the EUROCAT classification.

RESULTS

Of the 16,602 malformed singleton fetuses and newborns, 32.7% were detected postnatally. Of those with severe anomalies, 11.9% were detected postnatally. The postnatal detection rate decreased from 34.3% from 2001 to 2005, to 27.8% from 2016 to 2021 (P<.001). Anomalies most frequently detected postnatally were genital anomalies (n=969; 87.0%), followed by ear, neck, and face anomalies (n=71; 78.0%), eye anomalies (n=154; 74.0%), and limb anomalies (n=1802; 68.4%). Anomalies of the kidneys and the urinary tract (n=219; 7.1%) and the abdominal wall (n=37; 8.7%) were least likely to be detected after birth. Among the anomalies classified as severe, postnatal detection rates were highest for limb reduction defects (n=142; 40.6%), complete transposition of the great arteries (n=31; 17.6%), and diaphragmatic hernia (n=26; 17.2%).

CONCLUSION

Despite improvement of prenatal screening over a 20-year period, our results show that there is still a margin for improvement in prenatal diagnosis of congenital anomalies.

First-Trimester Ultrasound Imaging for Prenatal Assessment of the Extended Cardiovascular System Using the Cardiovascular System Sonographic Evaluation Algorithm (CASSEAL)

INTRODUCTION AND OBJECTIVES

To compare fetal images obtained at the first- and second-trimester ultrasound scan when applying the Cardiovascular System Sonographic Evaluation Algorithm (CASSEAL).

METHODS

Using the CASSEAL protocol, nine sequential axial views were acquired in B-mode and color Doppler at the first- and second-trimester ultrasound scans, visualizing the main components of the extended fetal cardiovascular system. Images were compared qualitatively between both trimesters.

RESULTS

We obtained comparable images for all the nine axial views described in the CASSEAL protocol, with few differences and limitations.

CONCLUSIONS

The CASSEAL protocol is reproducible in the first trimester, and could help in the early detection of fetal cardiovascular abnormalities. It represents a promising additional tool in order to increase the CHD detection rate.

Gestational age-specific neonatal mortality in Hong Kong: a population-based retrospective study

BACKGROUND

The neonatal period is the most vulnerable period during childhood, with the risk of death being the highest even in developed countries/regions. Hong Kong's neonatal mortality (1‰) is among the world's lowest and has remained similar for 15 years. This study aimed to explore neonatal deaths in Hong Kong in detail and determine whether neonatal mortality is reducible at such a low level.

METHODS

Live births in public hospitals in Hong Kong during 01 Jan 2006-31 Dec 2017 were included. Relevant data were extracted from the electronic medical records. Gestational age-specific mortality was calculated, and the trends were analyzed using the Cochran-Armitage trend test. Causes of death were summarized, and risk factors were identified in multivariate logistic regression analysis.

RESULTS

In 490,034 live births, 755 cases (1.54‰) died during the neonatal period, and 293 (0.6‰) died during the post-neonatal period. The neonatal mortality remained similar overall (P = 0.17) and among infants born at 24-29 weeks' gestation (P = 0.4), while it decreased in those born at 23 (P = 0.04), 30-36 (P < 0.001) and ≥ 37 (P < 0.001) weeks' gestation. Neonates born at < 27 weeks' gestation accounted for a significantly increased proportion among cases who died (27.6% to 51.9%), with hemorrhagic conditions (24%) being the leading cause of death. Congenital anomalies were the leading cause of death in neonates born ≥ 27 weeks' gestation (52%), but its cause-specific mortality decreased (P = 0.002, 0.6‰ to 0.41‰), with most of the decrease attributed to trisomy 13/18 and multiple anomalies.

CONCLUSION

Reduction of neonatal mortality in developed regions may heavily rely on improved quality of perinatal and neonatal care among extremely preterm infants.

Is the first-trimester combined screening result associated with the phenotype of Down syndrome? A population-based cohort study

OBJECTIVE

To investigate if the Down syndrome phenotype differs according to the result of first-trimester combined screening (FTS).

METHOD

We included all Down syndrome cases diagnosed by karyotype in pregnancy or after birth in Denmark during 2005-2018. We compared screen positive (odds ≥1:300) and screen negative (odds <1:300) cases as well as screen result subgroups with respect to anthropometrics, congenital malformations, childhood diseases, and hospitalization.

RESULTS

Absolute measures of fetal and birth anthropometrics were comparable between groups. A prenatal malformation diagnosis was more prevalent among screen positive than screen negative cases. Analyses suggested that this could reflect a detection bias. Cases with a screen result of 1:2-1:10 had a higher probability of being diagnosed with a malformation prenatally and with severe congenital heart disease (CHD) postnatally compared with a result of 1:11-1:300. Screen positive cases more often had non-severe CHD but less often a non-heart malformation compared with screen negative cases, while proportions of severe CHD were similar in these groups. Data on hospitalizations showed inconsistent results.

CONCLUSION

The 1:300 screening threshold had limited or no value in predicting Down syndrome phenotype severity. In contrast, cases with a screen result between 1:2 and 1:10 may represent a more severe phenotype.

Artificial intelligence in perinatal diagnosis and management of congenital heart disease

Prenatal diagnosis and management of congenital heart disease (CHD) has progressed substantially in the past few decades. Fetal echocardiography can accurately detect and diagnose approximately 85% of cardiac anomalies. The prenatal diagnosis of CHD results in improved care, with improved risk stratification, perioperative status and survival. However, there is much work to be done. A minority of CHD is actually identified prenatally. This seemingly incongruous gap is due, in part, to diminished recognition of an anomaly even when present in the images and the need for increased training to obtain specialized cardiac views. Artificial intelligence (AI) is a field within computer science that focuses on the development of algorithms that "learn, reason, and self-correct" in a human-like fashion. When applied to fetal echocardiography, AI has the potential to improve image acquisition, image optimization, automated measurements, identification of outliers, classification of diagnoses, and prediction of outcomes. Adoption of AI in the field has been thus far limited by a paucity of data, limited resources to implement new technologies, and legal and ethical concerns. Despite these barriers, recognition of the potential benefits will push us to a future in which AI will become a routine part of clinical practice.

First-trimester ultrasound detection of fetal heart anomalies: systematic review and meta-analysis

OBJECTIVES

To determine the diagnostic accuracy of ultrasound at 11-14 weeks' gestation in the detection of fetal cardiac abnormalities and to evaluate factors that impact the detection rate.

METHODS

This was a systematic review of studies evaluating the diagnostic accuracy of ultrasound in the detection of fetal cardiac anomalies at 11-14 weeks' gestation, performed by two independent reviewers. An electronic search of four databases (MEDLINE, EMBASE, Web of Science Core Collection and The Cochrane Library) was conducted for studies published between January 1998 and July 2020. Prospective and retrospective studies evaluating pregnancies at any prior level of risk and in any healthcare setting were eligible for inclusion. The reference standard used was the detection of a cardiac abnormality on postnatal or postmortem examination. Data were extracted from the included studies to populate 2 × 2 tables. Meta-analysis was performed using a random-effects model in order to determine the performance of first-trimester ultrasound in the detection of major cardiac abnormalities overall and of individual types of cardiac abnormality. Data were analyzed separately for high-risk and non-high-risk populations. Preplanned secondary analyses were conducted in order to assess factors that may impact screening performance, including the imaging protocol used for cardiac assessment (including the use of color-flow Doppler), ultrasound modality, year of publication and the index of sonographer suspicion at the time of the scan. Risk of bias and quality assessment were undertaken for all included studies using the Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) tool.

RESULTS

The electronic search yielded 4108 citations. Following review of titles and abstracts, 223 publications underwent full-text review, of which 63 studies, reporting on 328 262 fetuses, were selected for inclusion in the meta-analysis. In the non-high-risk population (45 studies, 306 872 fetuses), 1445 major cardiac anomalies were identified (prevalence, 0.41% (95% CI, 0.39-0.43%)). Of these, 767 were detected on first-trimester ultrasound examination of the heart and 678 were not detected. First-trimester ultrasound had a pooled sensitivity of 55.80% (95% CI, 45.87-65.50%), specificity of 99.98% (95% CI, 99.97-99.99%) and positive predictive value of 94.85% (95% CI, 91.63-97.32%) in the non-high-risk population. The cases diagnosed in the first trimester represented 63.67% (95% CI, 54.35-72.49%) of all antenatally diagnosed major cardiac abnormalities in the non-high-risk population. In the high-risk population (18 studies, 21 390 fetuses), 480 major cardiac anomalies were identified (prevalence, 1.36% (95% CI, 1.20-1.52%)). Of these, 338 were detected on first-trimester ultrasound examination and 142 were not detected. First-trimester ultrasound had a pooled sensitivity of 67.74% (95% CI, 55.25-79.06%), specificity of 99.75% (95% CI, 99.47-99.92%) and positive predictive value of 94.22% (95% CI, 90.22-97.22%) in the high-risk population. The cases diagnosed in the first trimester represented 79.86% (95% CI, 69.89-88.25%) of all antenatally diagnosed major cardiac abnormalities in the high-risk population. The imaging protocol used for examination was found to have an important impact on screening performance in both populations (P < 0.0001), with a significantly higher detection rate observed in studies using at least one outflow-tract view or color-flow Doppler imaging (both P < 0.0001). Different types of cardiac anomaly were not equally amenable to detection on first-trimester ultrasound.

CONCLUSIONS

First-trimester ultrasound examination of the fetal heart allows identification of over half of fetuses affected by major cardiac pathology. Future first-trimester screening programs should follow structured anatomical assessment protocols and consider the introduction of outflow-tract views and color-flow Doppler imaging, as this would improve detection rates of fetal cardiac pathology. © 2021 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Concordance Between Obstetric Anatomic Ultrasound and Fetal Echocardiography in Detecting Congenital Heart Disease in High-risk Pregnancies

OBJECTIVES

To evaluate the concordance between second-trimester anatomic ultrasound and fetal echocardiography in detecting minor and critical congenital heart disease in pregnancies meeting American Heart Association criteria.

METHODS

We conducted a retrospective cohort study of pregnancies in which a second-trimester fetal anatomic ultrasound examination (18-26 weeks) and fetal echocardiography were performed between 2012 and 2018 at our institution based on American Heart Association recommendations. Anatomic ultrasound studies were interpreted by maternal-fetal medicine specialists and fetal echocardiographic studies by pediatric cardiologists. Our primary outcome was the proportion of critical congenital heart disease (CCHD) cases not detected by anatomic ultrasound but detected by fetal echocardiography. The secondary outcome was the proportion of total congenital heart disease cases missed by anatomic ultrasound but detected by fetal echocardiography. Neonatal medical records were reviewed for all pregnancies when obtained and available.

RESULTS

Overall, 722 studies met inclusion criteria. Anatomic ultrasound and fetal echocardiography were in agreement in detecting cardiac abnormalities in 681(96.1%) studies (κ = 0.803; P < .001). The most common diagnosis not identified by anatomic ultrasound was a ventricular septal defect, accounting for 9 of 12 (75%) missed congenital heart defects. Of 664 studies with normal cardiac findings on the anatomic ultrasound examinations, no additional instances of CCHD were detected by fetal echocardiography. No unanticipated instances of CCHD were diagnosed postnatally.

CONCLUSIONS

With current American Heart Association screening guidelines, automatic fetal echocardiography in the setting of normal detailed anatomic ultrasound findings provided limited benefit in detecting congenital heart defects that would warrant immediate postnatal interventions. More selective use of automatic fetal echocardiography in at-risk pregnancies should be explored.

Prenatal detection of congenital heart disease - results of a Swedish screening program 2013-2017

Background

This report evaluates results of a screening program on prenatal detection of congenital heart defects in a geographical cohort of western Sweden between January 1st, 2013 and June 31st, 2017. During the study period 88,230 children were born in VGR.

Methods

Retrospective data on pregnant women from the Västra Götaland region that were referred to fetal cardiologists in Gothenburg were retrieved. To determine prenatal detection rate, all neonates who underwent surgery or catheter intervention for a critical congenital heart defect born between January 1st, 2014 and December 31st, 2016 were included. The four-chamber view was implemented into the routine scan in 2009 and implementation of the ISUOG guidelines, including the outflow tracts, started in the region in 2015.

Results

113 fetuses received a prenatal diagnosis of a major congenital heart defect. 89% of these were referred because of a suspected cardiac malformation and 88% were diagnosed before 22 completed weeks. 59% of the patients diagnosed before 22 completed weeks opted for termination of pregnancy. During 2014–2016, 61 fetuses had a prenatal diagnosis of a critical congenital heart defect and a further 47 were diagnosed after birth, hence 56% were diagnosed prenatally, 82% for those which had a combination with an extracardiac abnormality and/or chromosomal aberration compared to 50% if an isolated critical congenital heart defect was diagnosed. For single ventricle cardiac defects such as hypoplastic left heart syndrome, double inlet left ventricle and tricuspid atresia, the detection rate was 100%. The detection rate for transposition of the great arteries and coarctation of the aorta was 9 and 18% respectively.

Conclusions

56% of all fetuses with a critical congenital heart defect were diagnosed prenatally during 2014–2016 and approximately 53% of all major congenital heart defects 2013–2017 as compared to 13.8% in 2009 in the same region. An increased focus towards the fetal heart in the routine scan improved the prenatal detection rate of major congenital heart defects. The detection of congenital heart defects affecting the four-chamber view seems sufficient, but more training is needed to improve the quality of the examination of the outflow tracts.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12884-021-04028-5.

The current state of prenatal detection of genetic conditions in congenital heart defects

The incidence of congenital heart defect (CHD) has increased over the past fifty years, partly attributed to routine fetal anatomical examination by sonography during obstetric care and improvements in ultrasound technology and technique. Fetal findings on ultrasound in addition to maternal biomarkers are the backbone of first- and second-trimester screening for common genetic conditions, namely aneuploidy. Since the introduction of non-invasive prenatal testing (NIPT) using next-generation sequencing to sequence cell-free fetal DNA, the detection rate of common trisomies as well as sex chromosomal aneuploidies have markedly increased. As the use of NIPT continues to broaden, the best means of incorporating NIPT into prenatal care is less clear and complicated by misunderstanding of the limitations and non-diagnostic role of NIPT by clinicians and families. In other advancements in prenatal genetic testing, recommendations on the role of chromosomal microarray (CMA) for prenatal diagnosis has led to its increasing use to identify genetic conditions in fetuses diagnosed with CHD. Lastly, as whole exome sequencing (WES) becomes more available and affordable, the next clinical application of next-generation sequencing in prenatal diagnostic testing is on the horizon. While newer genetic tests may provide answers in terms of genetic diagnosis, even more questions will likely ensue for clinicians, researchers, and parents. The objective of this review is to provide the perspective of the evolution of maternal and fetal obstetric care against the backdrop of advancing genetic technology and its impact on families and clinicians.

Effectiveness of fetal ultrasound diagnostics in cardiac malformations and association with polyhydramnios and oligohydramnios

BACKGROUND

Examine the effectiveness of prenatal ultrasound diagnostics in the detection of cardiovascular malformations, and their association with polyhydramnios and oligohydramnios.

METHODS

We examined the fetal ultrasonography and postnatal clinical/fetopathological data of 372 newborns/fetuses over a 7-year period in a tertiary centre. Fetal echocardiography was performed in cases of suspected US findings between 18-32 weeks. During the ultrasound the amniotic fluid amount was measured and the amniotic fluid index (AFI) or largest amniotic fluid pocket was determined.

RESULTS

Prenatal ultrasonographic results and postnatal/fetopathological diagnosis were fully congruent in 236/372 cases (63.4%), and in 66/372 cases of cardiovascular anomalies (17.7%) the discovery was partial, while in 70/372 cases no fetal cardiovascular anomalies were diagnosed during pregnancy (18.8%) (false negative). Cardiovascular malformations were isolated in 255 cases, in 172 of which (67.5%) the results of prenatal ultrasonography and postnatal diagnostics were fully congruent. In 43 cases (16.9%) the prenatal discovery was partial, and in 40 cases (15.7%) there was no prenatal recognition of the malformation. Cardiovascular abnormalities were found as a part of multiple malformations in 76 cases. In 41 fetuses the cardiovascular malformation was associated with chromosomal abnormalities. Cardiovascular malformations were significantly associated with polyhydramnios. Although in some of the cardiovascular malformations the association rate with polyhydramnios was high (AVSD, double outlet right ventricle, tetralogy of Fallot), we found a moderate association rate (19.7%). The association with oligohydramnios was 8.57%.

CONCLUSIONS

Echocardiography plays an important role in the prenatal diagnostics. In cases of polyhydramnios and oligohydramnios, fetal echocardiography should be performed.

Examining ultrasound diagnostic performance improvement with utilization of maternal-fetal medicine tele-interpretation

BACKGROUND

Telemedicine can extend essential health services to under-resourced settings and improve the quality of obstetrical care. Specifically, the evaluation and management of fetal anomalies require perinatal subspecialists, rendering prenatal diagnosis essential, and may benefit from telemedicine platforms to improve access to care.

OBJECTIVE

This study aimed to evaluate the impact of a maternal-fetal medicine telemedicine ultrasound program on the diagnostic accuracy of fetal anomalies when used within practices where ultrasounds are interpreted by general obstetricians or family medicine physicians.

STUDY DESIGN

This was a cross-sectional study of all patients receiving care at 11 private obstetrical practices and imaging centers who had obstetrical ultrasounds performed from January 1, 2020, to July 6, 2020. All ultrasounds were performed by sonographers remotely trained under a standardized protocol and interpreted by maternal-fetal medicine physicians via telemedicine. Ultrasound characteristics and interpretation were extracted from ultrasound reports. Before the introduction of maternal-fetal medicine telemedicine, all ultrasound interpretations were reviewed by general obstetricians and family medicine physicians with reliance predominantly on the sonographer's impression. The primary outcome was potential missed diagnosis of a fetal anomaly, defined as an ultrasound designated as normal by a sonographer but diagnosed with an anomaly by a maternal-fetal medicine physician via telemedicine. This outcome serves as a proxy measure for anomaly diagnoses that would likely be missed without the supervision of a maternal-fetal medicine physician. The characteristics of the potential missed diagnoses were compared by type of scan and fetal organ system in univariable analysis. Moreover, a survey was conducted for sonographers and obstetrical providers to assess their perceptions of ultrasound interpretation via telemedicine.

RESULTS

Overall, 6403 ultrasound examinations were evaluated, 310 of which had a diagnosis of fetal anomaly by a maternal-fetal medicine physician (4.8%). Of the fetal anomalies, 43 were diagnosed on an anatomic survey (13.9%), and 89 were diagnosed as cardiac anomalies (28.7%). The overall rate of the potential missed diagnoses was 34.5% and varied significantly by type of ultrasound (anatomy scans vs other first-, second-, and third-trimester ultrasounds) (P<.01). Moreover, there were significant differences in the rate of the potential missed diagnoses by organ system, with the highest rate for cardiac anomalies (P<.01).

CONCLUSION

Expertise in maternal-fetal medicine telemedicine improves the diagnostic performance of antenatal ultrasound throughout pregnancy. However, there are implications for improving the quality of antenatal care, such as ensuring appropriate referrals and site of delivery, particularly for cardiac anomalies.

Impact of maternal obesity on fetal cardiac screening: which follow-up strategy is cost-effective?

OBJECTIVE

To perform a cost-effectiveness analysis of different follow-up strategies for non-obese and obese women who had incomplete fetal cardiac screening for major congenital heart disease (CHD).

METHODS

Three decision-analytic models, one each for non-obese, obese and Class-III-obese women, were developed to compare five follow-up strategies for initial suboptimal fetal cardiac screening. The five strategies were: (1) no follow-up ultrasound (US) examination but direct referral to fetal echocardiography (FE); (2) one follow-up US, then FE if fetal cardiac views were still suboptimal; (3) up to two follow-up US, then FE if fetal cardiac views were still suboptimal; (4) one follow-up US and no FE; and (5) up to two follow-up US and no FE. The models were designed to identify fetuses with major CHD in a theoretical cohort of 4 000 000 births in the USA. Outcomes related to neonatal mortality and neurodevelopmental disability were evaluated. A cost-effectiveness willingness-to-pay threshold was set at US$100 000 per quality-adjusted life year (QALY). Base-case and sensitivity analysis and Monte-Carlo simulation were performed.

RESULTS

In our base-case models for all body mass index (BMI) groups, no follow-up US, but direct referral to FE led to the best outcomes, detecting 7%, 25% and 82% more fetuses with CHD in non-obese, obese and Class-III-obese women, respectively, compared with the baseline strategy of one follow-up US and no FE. However, no follow-up US, but direct referral to FE was above the US$100 000/QALY threshold and therefore not cost-effective. The cost-effective strategy for all BMI groups was one follow-up US and no FE. Both up to two follow-up US with no FE and up to two follow-up US with FE were dominated (being more costly and less effective), while one follow-up US with FE was over the cost-effectiveness threshold. One follow-up US and no FE was the optimal strategy in 97%, 93% and 86% of trials in Monte-Carlo simulation for non-obese, obese and Class-III-obese models, respectively.

CONCLUSION

For both non-obese and obese women with incomplete fetal cardiac screening, the optimal CHD follow-up screening strategy is no further US and immediate referral to FE; however, this strategy is not cost-effective. Considering costs, one follow-up US and no FE is the preferred strategy. For both obese and non-obese women, Monte-Carlo simulations showed clearly that one follow-up US and no FE was the optimal strategy. Both non-obese and obese women with initial incomplete cardiac screening examination should therefore be offered one follow-up US. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.

Detection of fetal cardiac anomalies: cost-effectiveness of increased number of cardiac views

OBJECTIVE

To compare the recommended three-view fetal heart screening method to detect major congenital heart disease (CHD) with more elaborate screening strategies to determine the cost-effective strategy in unselected (low-risk) pregnancies.

METHODS

A decision-analytic model was designed to compare four screening strategies to identify fetuses with major CHD in a theoretical cohort of 4 000 000 births in the USA. The four strategies were: (1) three views: four-chamber view (4CV) and views of the left (LVOT) and right (RVOT) ventricular outflow tracts; (2) five views: 4CV, LVOT, RVOT and longitudinal views of the ductal arch and aortic arch; (3) five axial views: 4CV, LVOT, RVOT, three-vessel (3V) view and three-vessels-and-trachea view; and (4) six views: 4CV, LVOT, RVOT and 3V views and longitudinal views of the ductal arch and aortic arch. Outcomes related to neonatal mortality and neurodevelopmental disability were evaluated. The analysis was performed from a healthcare-system perspective, with a cost-effectiveness willingness-to-pay threshold set at $100 000 per quality-adjusted life year (QALY). Baseline analysis, one-way sensitivity analysis and Monte-Carlo simulation were performed.

RESULTS

In our baseline model, screening with five axial views was the optimal strategy, detecting 3520 more CHDs, and resulting in 259 fewer children with neurodevelopmental disability, 40 fewer neonatal deaths and only slightly higher costs, compared with screening with the currently recommended three views. Screening with six views was more effective, but also cost considerably more, compared with screening with five axial views, and had an incremental cost of $490 023/QALY, which was over the willingness-to-pay threshold. The five-view strategy was dominated by the other three strategies, i.e. it was more costly and less effective in comparison. The data were robust when tested with Monte-Carlo and one-way sensitivity analysis.

CONCLUSION

Although current guidelines recommend a minimum of three views for detecting CHD during the mid-trimester anatomy scan, screening with five axial views is a cost-effective strategy that may lead to improved outcome compared with three-view screening. Copyright © 2020 ISUOG. Published by John Wiley & Sons Ltd.

Physician Barriers and Facilitators for Screening for Congenital Heart Disease With Routine Obstetric Ultrasound: A National United States Survey

OBJECTIVES

Prenatal detection of congenital heart disease with obstetric screening remains at less than 50% in most population studies, far from what is thought to be achievable. We sought to identify barriers/facilitators for screening from the perspective of interpreting physicians and to understand how these barriers/facilitators may be associated with interpretation of screening images.

METHODS

Our mixed-methods studies included 4 focus groups in centers across the United States with obstetric, maternal-fetal medicine, and radiology providers who interpreted obstetric ultrasound studies. Themes around barriers/facilitators for fetal heart screening were coded from transcripts. A national Web-based survey was then conducted, which quantitatively measured reported barriers/facilitators and measured physicians' ability to interpret fetal heart-screening images. Multivariable generalized linear random-effect models assessed the association between barriers/facilitators and the accuracy of image interpretation at the image level.

RESULTS

Three main themes were identified in the focus groups: intrinsic barriers (ie, comfort with screening), external barriers (ie, lack of feedback), and organizational barriers (ie, study volumes). Among 190 physician respondents, 104 interpreted ultrasound studies. Perceptions of barriers varied by practice setting, with nontertiary providers having lower self-efficacy and perceived usefulness of cardiac screening. Facilitators associated with the odds of accurate interpretation of screening images were knowledge (odds ratio, 2.54; P = .002) and the volume of scans per week (odds ratio, 1.01 for every additional scan; P = .04).

CONCLUSIONS

Some of the main barriers to cardiac screening identified and prioritized by physicians across the United States were knowledge of screening and minimal volumes of scans. Targeting these barriers will aid in improving prenatal detection of congenital heart disease.

Why are congenital heart defects being missed?

OBJECTIVE

Congenital heart defects (CHD) are still missed frequently in prenatal screening programs, which can result in severe morbidity or even death. The aim of this study was to evaluate the quality of fetal heart images, obtained during the second-trimester standard anomaly scan (SAS) in cases of CHD, to explore factors associated with a missed prenatal diagnosis.

METHODS

In this case-control study, all cases of a fetus born with isolated severe CHD in the Northwestern region of The Netherlands, between 2015 and 2016, were extracted from the PRECOR registry. Severe CHD was defined as need for surgical repair in the first year postpartum. Each cardiac view (four-chamber view (4CV), three-vessel (3V) view and left and right ventricular outflow tract (LVOT, RVOT) views) obtained during the SAS was scored for technical correctness on a scale of 0 to 5 by two fetal echocardiography experts, blinded to the diagnosis of CHD and whether it was detected prenatally. Quality parameters of the cardiac examination were compared between cases in which CHD was detected and those in which it was missed on the SAS. Regression analysis was used to assess the association of sonographer experience and of screening-center experience with the cardiac examination quality score.

RESULTS

A total of 114 cases of isolated severe CHD at birth were analyzed, of which 58 (50.9%) were missed and 56 (49.1%) were detected on the SAS. The defects comprised transposition of the great arteries (17%), aortic coarctation (16%), tetralogy of Fallot (10%), atrioventricular septal defect (6%), aortic valve stenosis (5%), ventricular septal defect (18%) and other defects (28%). No differences were found in fetal position, obstetric history, maternal age or body mass index (BMI) or gestational age at examination between missed and detected cases. Ninety-two cases had available cardiac images from the SAS. Compared with the detected group, the missed group had significantly lower cardiac examination quality scores (adequate score (≥ 12) in 32% vs 64%; P = 0.002), rate of proper use of magnification (58% vs 84%; P = 0.01) and quality scores for each individual cardiac plane (4CV (2.7 vs 3.9; P < 0.001), 3V view (3.0 vs 3.8; P = 0.02), LVOT view (1.9 vs 3.3; P < 0.001) and RVOT view (1.9 vs 3.3; P < 0.001)). In 49% of missed cases, the lack of detection was due to poor adaptational skills resulting in inadequate images in which the CHD was not clearly visible; in 31%, the images showed an abnormality (mainly septal defects and aortic arch anomalies) which had not been recognized at the time of the scan; and, in 20%, the cardiac planes had been obtained properly but showed normal anatomy. Multivariate regression analysis showed that the volume of SAS performed per year by each sonographer was associated significantly with quality score of the cardiac examination.

CONCLUSIONS

A lack of adaptational skills when performing the SAS, as opposed to circumstantial factors such as BMI or fetal position, appears to play an important role in failure to detect CHD prenatally. The quality of the cardiac views was inadequate significantly more often in undetected compared with detected cases. Despite adequate quality of the images, CHD was not recognized in 31% of cases. A high volume of SAS performed by each sonographer in a large ultrasound center contributes significantly to prenatal detection. In 20% of undetected cases, CHD was not visible even though the quality of the images was good. © 2019 Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Barriers to Sonographer Screening for Fetal Heart Defects: A U.S. National Survey

OBJECTIVE

We surveyed obstetric sonographers, who are at the forefront of the screening process to determine how barriers to prenatal cardiac screening impacted screening abilities.

METHODS

We performed a cross-sectional national survey of obstetric sonographers in the United States using a sampling frame from American Registry of Diagnostic Medical Sonography mailing lists. The web survey measured the ability to obtain and interpret fetal heart images. Several cognitive, sociodemographic, and system-level factors were measured, including intention to perform cardiac imaging. Regression and mediation analyses determined factors associated with intention to perform and ability to obtain and interpret cardiac images. Subgroup analyses of sonographers in tertiary versus nontertiary centers were also performed.

RESULTS

Survey response rate either due to noncontact or nonresponse was 40%. Of 480 eligible sonographers, ~30% practiced in tertiary settings. Sonographers had lower intention to perform outflow views compared to 4 chambers. Higher self-efficacy and professional expectations predicted higher odds of intention to perform outflow views (OR 2.8, 95% CI 1.9-4.2 and 1.9, 95% CI 1.1-3.0, respectively). Overall accuracy of image interpretation was 65% (±14%). For the overall cohort and nontertiary subgroup, higher intention to perform outflows was associated with increased accuracy in overall image interpretation. For the tertiary subgroup, self-efficacy and feedback were strongly associated with accuracy.

CONCLUSIONS

We identified several modifiable (some heretofore unrecognized) targets to improve prenatal cardiac screening. Priorities identified by sonographers that are associated with screening success should guide future interventions.

Prenatal diagnosis and prevalence of critical congenital heart defects: an international retrospective cohort study

OBJECTIVES

To assess international trends and patterns of prenatal diagnosis of critical congenital heart defects (CCHDs) and their relation to total and live birth CCHD prevalence and mortality.

SETTING

Fifteen birth defect surveillance programmes that participate in the International Clearinghouse for Birth Defects Surveillance and Research from 12 countries in Europe, North and South America and Asia.

PARTICIPANTS

Live births, stillbirths and elective terminations of pregnancy for fetal anomaly diagnosed with 1 of 12 selected CCHD, ascertained by the 15 programmes for delivery years 2000 to 2014.

RESULTS

18 243 CCHD cases were reported among 8 847 081 births. The median total prevalence was 19.1 per 10 000 births but varied threefold between programmes from 10.1 to 31.0 per 10 000. CCHD were prenatally detected for at least 50% of the cases in one-third of the programmes. However, prenatal detection varied from 13% in Slovak Republic to 87% in some areas in France. Prenatal detection was consistently high for hypoplastic left heart syndrome (64% overall) and was lowest for total anomalous pulmonary venous return (28% overall). Surveillance programmes in countries that do not legally permit terminations of pregnancy tended to have higher live birth prevalence of CCHD. Most programmes showed an increasing trend in prenatally diagnosed CCHD cases.

DISCUSSION AND CONCLUSIONS

Prenatal detection already accounts for 50% or more of CCHD detected in many programmes and is increasing. Local policies and access likely account for the wide variability of reported occurrence and prenatal diagnosis. Detection rates are high especially for CCHD that are more easily diagnosed on a standard obstetric four-chamber ultrasound or for fetuses that have extracardiac anomalies. These ongoing trends in prenatal diagnosis, potentially in combination with newborn pulse oximetry, are likely to modify the epidemiology and clinical outcomes of CCHD in the near future.

The Combined Use of Ultrasound and Fetal Magnetic Resonance Imaging for a Comprehensive Fetal Neurological Assessment in Fetal Congenital Cardiac Defects: Scientific Impact Paper No. 60

Heart problems are common in newborn babies, affecting approximately 5-10 in 1000 babies. Some are more serious than others, but most babies born with heart problems do not have other health issues. Of those babies who have a serious heart problem, almost 1 in 4 will have heart surgery in their first year. In the UK, pregnant women are offered a scan at around 20 weeks to try and spot any heart problems. In most cases there is not a clear reason for the problem, but sometimes other issues, such as genetic conditions, are discovered. In recent years the care given to these babies after they are born has improved their chances of surviving. However, it is recognised that babies born with heart problems have a risk of delays in their learning and development. This may be due to their medical condition, or as a result of surgery and complications after birth. In babies with heart problems, there is a need for more research on ultrasound and magnetic resonance imaging (MRI) to understand how the brain develops and why these babies are more likely to have delays in learning and development. This paper discusses the way ultrasound and MRI are used in assessing the baby's brain. Ultrasound is often used to spot any problems, looking at how the baby's brain develops in pregnancy. Advances in ultrasound technologies have made this easier. MRI is well-established and safe in pregnancy, and if problems in the brain have been seen on ultrasound, MRI may be used to look at these problems in more detail. While it is not always clear what unusual MRI findings can mean for the baby in the long term, increased understanding may mean parents can be given more information about possible outcomes for the baby and may help to improve the counselling they are offered before their baby's birth.

Fetal Intelligent Navigation Echocardiography (FINE) Detects 98% of Congenital Heart Disease

OBJECTIVE

Fetal intelligent navigation echocardiography (FINE) is a novel method that automatically generates and displays 9 standard fetal echocardiographic views in normal hearts by applying intelligent navigation technology to spatiotemporal image correlation (STIC) volume data sets. The main objective was to determine the sensitivity and specificity of FINE in the prenatal detection of congenital heart disease (CHD).

METHODS

A case-control study was conducted in 50 fetuses with a broad spectrum of CHD (cases) and 100 fetuses with normal hearts (controls) in the second and third trimesters. Using 4-dimensional ultrasound with STIC technology, volume data sets were acquired. After all identifying information was removed, the data sets were randomly distributed to a different investigator for analysis using FINE. The sensitivity and specificity for the prenatal detection of CHD, as well as positive and negative likelihood ratios were determined.

RESULTS

The diagnostic performance of FINE for the prenatal detection of CHD was: sensitivity of 98% (49 of 50), specificity of 93% (93 of 100), positive likelihood ratio of 14, and negative likelihood ratio of 0.02. Among cases with confirmed CHD, the diagnosis with use of FINE completely matched the final diagnosis in 74% (37 of 50); minor discrepancies were seen in 12% (6 of 50), and major discrepancies were seen in 14% (7 of 50).

CONCLUSIONS

This is the first time the sensitivity and specificity of the FINE method in fetuses with normal hearts and CHD in the second and third trimesters has been reported. Because FINE identifies a broad spectrum of CHD with 98% sensitivity, this method could be used prenatally to screen for and diagnose CHD.

Sonographer-Identified Barriers and Facilitators to Prenatal Screening for Congenital Heart Disease

Background: Fetal ultrasound screening for congenital heart disease has high detection rates in efficacy studies but not in practice. We investigated sonographers’ perspectives on barriers to screening and their association with intermediate measures of cardiac imaging. Methods: Barriers to fetal heart screening were identified in focus groups with obstetric sonographers. A web-based survey measured reported barriers and sonographers’ ability to interpret fetal heart screening images. Generalized linear random effect models assessed associations between barriers and image interpretation. Results: Four themes were identified: intrinsic barriers (self-efficacy), external barriers (time), informational needs, and provider and patient expectations. Among 224 sonographers surveyed, an average of 77.6% of fetal heart images were interpreted correctly. Perceptions about self-efficacy ( P = .03) and ease of performing imaging ( P = .01) were associated with accuracy of image interpretation. Conclusions: Several sonographer-identified barriers associated with image interpretation may be novel targets for improving prenatal detection of congenital heart disease.

Screening for Congenital Heart Disease

Compared with the assessment of most fetal anatomic structures, the assessment of the fetal heart during routine obstetric screening represents a diagnostic challenge for sonographers and interpreting physicians. This is due to a number of factors: the structural complexity of the heart, the rate at which it moves, the position of the fetus relative to the transducer, and variations in assessment protocols used by sonographers and physicians. The fetal heart is a relatively small and complex structure, as seen in an early second-trimester sonogram. In some forms of congenital heart disease, the abnormality may be detectable within only a relatively small fraction of the heart volume. Congenital heart disease represents a range of structural defects, a number of which have specific sonographic features that can be identified during routine assessment. Many approaches have been proposed to improve the assessment of the fetal heart, including specific still images, color Doppler, 3D imaging techniques, and cineloops.

How to Acquire Cardiac Volumes for Sonographic Examination of the Fetal Heart: Part 2

The effective performance of fetal cardiac examination using spatiotemporal image correlation (STIC) technology requires 2 essential steps: volume acquisition and postprocessing. An important prerequisite is training sonologists to acquire high-quality volume data sets so that when analyzed, such volumes are informative. This article is part 2 of a series on 4-dimensional sonography with STIC. Part 1 focused on STIC technology and its features, the importance of operator training/experience and acquisition of high-quality STIC volumes, factors that affect STIC volume acquisition rates, and general recommendations on performing 4D sonography with STIC. In part 2, we discuss a detailed and practical stepwise approach for STIC volume acquisition, along with methods to determine whether such volumes are appropriate for analysis.

How to Acquire Cardiac Volumes for Sonographic Examination of the Fetal Heart: Part 1

Four-dimensional sonography with spatiotemporal image correlation (STIC) technology allows acquisition of a fetal cardiac volume data set and displays a cine loop of a complete single cardiac cycle in motion. Part 1 of this 2-part article reviews STIC technology and its features, the importance of operator training/experience, and acquisition of high-quality STIC volumes, as well as factors that affect STIC volume acquisition rates. We also propose a detailed and practical stepwise approach to performing 4-dimensional sonography with STIC and begin herein by providing general recommendations. Part 2 will discuss specifics of the approach, along with how to determine whether such volumes are appropriate for analysis.

Prenatal Counseling and Care for Single-Ventricle Heart Disease: One Center’s Model for Care

Advances in prenatal imaging allow early detection of single-ventricle congenital heart disease, which may enhance prenatal care and maximize care options and decision making. Boston Children’s Hospital’s Advanced Fetal Care Center and fetal cardiology program provide prenatal counseling and care for single-ventricle congenital heart disease. Key points for optimal prenatal counseling and education include explanation of the diagnosis, delivery, the first surgery, cardiac neurodevelopmental issues, feeding and growth issues, quality of life and long-term care, family stressors, and fetal cardiac intervention. Such counseling and education help families make the difficult decisions required in this situation.

Pediatric prenatal diagnosis of congenital heart disease

PURPOSE OF REVIEW

Fetal cardiology is a rapidly evolving field. Imaging technology continues to advance as do approaches to in-utero interventions and care of the critically ill neonate, with even greater demand for improvement in prenatal diagnosis of congenital heart disease (CHD) and arrhythmias.

RECENT FINDINGS

Reviewing the advances in prenatal diagnosis of CHD in such a rapidly developing field is a broad topic. Therefore, we have chosen to focus this review of recent literature on challenges in prenatal detection of CHD, challenges in prenatal counseling, advances in fetal arrhythmia diagnosis, and potential benefits to patients with CHD who are identified prenatally.

SUMMARY

As methods and tools to diagnose and manage CHD and arrhythmias in utero continue to improve, future generations will hopefully see a reduction in both prenatal and neonatal morbidity and mortality. Prenatal diagnosis can and should be used to optimize location and timing of delivery and postnatal interventions.

Psychosocial risk in families of infants undergoing surgery for a serious congenital heart disease

OBJECTIVE

The aim of this study was to explore the acute psychosocial risk in families with infants undergoing surgery for a congenital heart disease and, secondarily, to explore the psychosocial impact of antenatal versus post-natal diagnoses.

METHOD

The study sample comprised 39 caregivers (28 mothers) of 29 children diagnosed with a congenital heart disease and requiring surgery within the first 4 weeks of life. Psychosocial risk was measured using the Psychosocial Assessment Tool, which was adapted to include four novel items examining infant risk factors, namely, sleeping, feeding, crying, and bonding difficulties. Parents' psychosocial risk was measured within 4 weeks after their child's surgery and stratified into a three-tiered framework: Universal, Targeted, and Clinical risk.

RESULTS

Of the total sample, 61.5% of parents were classified as Universal, that is, at lowest risk; 35.9% as Targeted, and 2.6% as Clinical. The within-family parent total Psychosocial Assessment Tool score correlations were non-significant, and there were no differences between families of infants who received post-natal versus antenatal diagnosis or single ventricle versus biventricular repair. Linear regression found that a higher parent education significantly predicted a lower total Psychosocial Assessment Tool score.

CONCLUSIONS

Findings indicate that, although the majority of parents adapt to the acute stress of surgery for a serious cardiac illness in their infant, the remaining 38.5% report an increased psychosocial risk associated with higher rates of emotional distress, which may impact on the parental quality of life and capacity for optimal parenting. The distribution of psychosocial risk in parents of children undergoing surgery for a congenital heart disease is consistent with that described for parents of children with other serious paediatric diagnoses.

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.

Evaluation of the fetal heart at 14 to 18 weeks' gestation in fetuses with a screening nuchal translucency greater than or equal to the 95th percentile

OBJECTIVES

The purpose of this study was to determine whether normal fetal cardiac anatomy could be successfully demonstrated and congenital heart disease detected transabdominally at 14 to 18 weeks' gestation in fetuses with a nuchal translucency greater than or equal to the 95th percentile.

METHODS

In this retrospective chart review, grayscale images, Z scores, and Doppler evaluations, including pulsed, color, and spectral Doppler imaging, were reviewed to determine whether fetal heart evaluation findings at 14 to 18 weeks' gestation were normal or abnormal.

RESULTS

Normal cardiac anatomy was successfully evaluated in 32 of 33 normal cases; only an aortic arch and a ductal arch were not successfully visualized in 1 case. Major congenital heart disease was detected prenatally in 4 abnormal cases.

CONCLUSIONS

The fetal heart can be successfully evaluated at an earlier gestational age but may be dependent on the skill of the sonographer and reading physician. Maternal decisions can be made earlier in gestation, before the pregnancy is obvious, and can allow planning for a pregnancy that will need to be delivered at a medical center that has a level 3 nursery.

Timing of ultrasound in pregnancy--how often? At what intervals?

The second trimester fetal anatomic survey has continued to evolve over the past 27 years. This review will summarize the changes in the anatomic survey that have occurred and provide recommendations that serve to improve compliance with the components of the survey. In order to provide clarity and direction, the goals and limitations of the second trimester fetal anatomic survey should be defined. The visualization rate of specific fetal anatomic structures can be increased by specifying acceptable, alternative views. A single follow-up examination within 2-4 weeks of a fetal anatomic survey or before 22 weeks' gestation should be offered when specific components of the fetal anatomic survey cannot be visualized. The fetal anomalies that the anatomic survey seeks to identify should be defined along with an acceptable detection rate.

[Contribution of volume ultrasound in the evaluation and prenatal care of fetal cardiovascular anomalies]

OBJECTIVES

To highlight the value of 3D ultrasound in the prenatal assessment of fetal cardiovascular abnormalities.

PATIENTS AND METHODS

A retrospective offline analysis of volume datasets of fetuses diagnosed with cardiovascular anomalies by 2D ultrasound was performed.

RESULTS

Thirty-four fetuses with 38 cardiac malformations were evaluated. Mean gestational age at diagnosis was 26 weeks. Isolated cardiovascular malformations were detected in 23 fetuses. Extracardiac abnormalities were identified in eight fetuses. Ten terminations of pregnancy were performed.

CONCLUSION

Offline analysis of cardiovascular anomalies conferred significant diagnostic advantages over 2D ultrasound. 3D ultrasound is a valuable tool for the prenatal diagnosis and the management of congenital heart diseases.

Performance of different scan protocols of fetal echocardiography in the diagnosis of fetal congenital heart disease: a systematic review and meta-analysis

OBJECTIVE

The rapid progress in fetal echocardiography has lead to early detection of congenital heart diseases. Increasing evidences have shown that prenatal diagnosis could be life saving in certain cases. However, there is no agreement on which protocol is most adaptive diagnostic one. Thus, we use meta-analysis to conduct a pooled performance test on 5 diagnostic protocols.

METHODS

We searched PUBMED, EMBASE, the Cochrane Central Register of Controlled Trials and WHO clinical trails registry center to identify relevant studies up to August, 2012. We performed meta-analysis in a fixed/random-effect model using Meta-disc 1.4. We used STATA 11.0 to estimate the publication bias and SPSS 17.0 to evaluate variance.

RESULTS

We use results from 81 studies in 63 articles to analyze the pooled accuracy. The overall performance of pooled sensitivities of spatiotemporal image correlation (STIC), extend cardiac echography examination (ECEE) and 4 chambers view + outflow tract view + 3 vessels and trachea view (4 CV+OTV+3 VTV) were around 0.90, which was significant higher than that of 4 chambers view + outflow tract view or 3 vessels and trachea view (4 CV+OTV/3 VTV) and 4 chambers view (4 CV). Unfortunately the pooled specificity of STIC was 0.92, which was significant lower than that of other 4 protocols which reached at 1.00. The area under the summary receiver operating characteristic curves value of STIC, ECEE, 4 CV+OTV+3 VTV, 4 CV+OTV/3 VTV and 4 CV were 0.9700, 0.9971, 0.9983, 0.9929 and 0.9928 respectively.

CONCLUSION

These results suggest a great diagnostic potential for fetal echocardiography detection as a reliable method of fetal congenital heart disease. But at least 3 sections view (4 CV, OTV and 3 VTV) should be included in scan protocol, while the STIC can be used to provide more information for local details of defects, and can not be used to make a definite diagnosis alone with its low specificity.

Education in obstetrical ultrasound--an important factor for increasing the prenatal detection of congenital heart disease

OBJECTIVE

To evaluate the effects of postgraduate education in obstetrical ultrasound on the prenatal detection rate of congenital heart disease.

SETTING

Tertiary care center.

POPULATION

Experienced and less experienced midwives performing ultrasound scans.

METHODS

Number of fetuses and live-born children with severe congenital heart malformations were extracted from patient records. The detection rates of experienced and less experienced midwives were compared following a postgraduate training program in obstetrical ultrasound.

MAIN OUTCOME MEASURES

The prenatal detection rate of complex congenital heart malformations.

RESULTS

The prenatal detection rate for the entire unit increased significantly during the study period (32 vs. 69%, p < 0.05). Following education, we observed a significant increase in detection rates (21 vs. 67%, p < 0.01) among experienced midwives. In the group of less experienced midwives, we found a positive effect of training with considerably higher detection rates compared with results achieved by their more experienced colleagues before the program (40 vs. 21%).

CONCLUSION

There is a clear improvement in the prenatal detection rates of complex heart malformations following a postgraduate education in obstetrical ultrasound. Similar training should be offered to both midwives and doctors performing routine scans to increase the standards of antenatal screening for congenital heart disease.

Barriers to prenatal detection of congenital heart disease: a population-based study

OBJECTIVE

To evaluate the extent and determinants of missed prenatal detection of congenital heart disease (CHD) in a population-based setting.

METHODS

This was a retrospective cohort study of cases with CHD, excluding minor defects, identified between 1997 and 2007 by a statewide surveillance program. We examined a comprehensive list of potential risk factors for which data were available in the surveillance database from abstracted medical charts. We analyzed the association of fetal, maternal and encounter factors with 1) whether a prenatal ultrasound was performed and 2) prenatal detection of CHD.

RESULTS

CHD was detected prenatally in only 39% of 1474 cases, with no improvement in detection rate over the 10-year period. Among the 97% (n = 1431) of mothers who underwent one or more ultrasound examinations, 35% were interpreted as abnormal; fetal echocardiography was performed in 27% of the entire cohort. Maternal and encounter factors increasing the adjusted odds of prenatal detection included: family history of CHD (OR, 4.3 (95% CI, 1.9-9.9)), presence of extracardiac defects (OR, 2.7 (95% CI, 1.9-3.9)) and ultrasound location i.e. high risk clinic vs clinic (OR, 2.1 (95% CI, 1.3-3.1)). Defects that would be expected to have an abnormal outflow-tract view were missed more often (64%) than were those that would be expected to have an abnormal four-chamber view (42%).

CONCLUSION

The majority of CHD cases over the 10-year study period were missed prenatally and detection rates did not increase materially during that time. The failure to detect CHD prenatally was related to encounter characteristics, specifically involving screening ultrasound examinations, which may be targeted for improvement.

Congenital cardiac anomalies: prenatal readings versus neonatal outcomes

OBJECTIVE

The purpose of this study was to determine the variation between prenatal and postnatal diagnosis of congenital cardiac lesions diagnosed by both fetal center primary physicians and fetal pediatric cardiologists at a single tertiary referral center in the United States and evaluate why cases were misdiagnosed.

METHODS

A retrospective review of all cardiac abnormalities identified prenatally by level II sonography at a tertiary referral fetal center between January 2006 and December 2008 was performed to include any patient with a fetal cardiac abnormality and with a documented autopsy or neonatal follow-up. Congenital heart disease diagnoses were classified as correct, incorrect, or incorrect but within the same spectrum of disease. Cases of correct diagnosis by primary physicians and pediatric cardiologists were compared.

RESULTS

Sixty patients with fetal heart abnormalities were identified among 8894 patients who had level II sonography. The combined detection rate for fetal heart abnormalities for both primary physicians and pediatric cardiologists together was 81.7%. The detection rates of congenital heart disease were not statistically different between primary physicians and pediatric cardiologists: 77.9% (46 of 59) versus 85.0% (34 of 40; P = .3). The most common cardiac abnormalities misdiagnosed in our study population included pulmonic stenosis, ventricular septal defect, myxoma, truncus arteriosus, and coarctation of the aorta.

CONCLUSIONS

Congenital heart disease is misdiagnosed in tertiary care centers by both pediatric cardiologists and fetal imaging specialists. We believe that this occurrence is related to multiple factors, including evolution of congenital heart disease, maternal body habitus, associated congenital anomalies, decreased amniotic fluid volume, gestational age at evaluation, imaging techniques, and, most importantly, the experience of the sonographer.

Scan the fetal heart by real-time three-dimensional echocardiography with live xPlane imaging

OBJECTIVE

To describe the methodology of live xPlane imaging in the visualization of the fetal heart in detail.

METHODS

Fifty-one consecutive pregnant women with singleton pregnancies were imaged to display four screening sections of the fetal heart, the four-chamber view, the left outflow tract view (LVOT), the right outflow tract view (RVOT), and the three-vessel and trachea view (3VT), using live xPlane imaging. The methodology of how to visualize the screening planes was described in detail. We used two methods to image the fetal heart with live xPlane imaging: one uses the four-chamber view as the starting plane and the other uses the longitudinal view of fetal upper thorax as the starting plane.

RESULTS

When using the four-chamber view as the starting plane, the visualization rate of LVOT, RVOT, and 3VT was 94.1% (48/51), 100% (51/51), and 98.0% (50/51), respectively. When using the longitudinal view as the starting plane, the visualization rate of four-chamber view, LVOT, RVOT, and 3VT was 100% (51/51), 100% (51/51), 41.2% (21/51), and 100% (51/51), respectively.

CONCLUSIONS

Live xPlane imaging can be used to visualize the screening views of the fetal heart, and potentially may be a useful tool for the assessment and diagnosis of fetal congenital heart diseases.

Obstetrical sonography in obese women: a review

Obstetric sonographic imaging in pregnant women is adversely affected by obesity with a negative impact on the detection rate of congenital anomalies. This review aims to analyze relevant data regarding this issue and to discuss clinical and technical problems associated with sonographic examination of obese pregnant women.

Real-time three-dimensional echocardiography using a matrix probe with live xPlane imaging of the interventricular septum

OBJECTIVE

To describe a technique to rapidly visualize the in-plane view of the fetal interventricular septum (IVS) to enable the identification of a ventricular septal defect (VSD).

METHODS

One hundred and fifty-one women were invited to participate after their routine fetal morphology scan, including four suspected to have congenital cardiac defects which were confirmed postnatally. A standard examination protocol using real-time three-dimensional (3D) echocardiography with live xPlane imaging was developed. The ability of this new technology to examine the ventricular septum was investigated.

RESULTS

The in-plane view of the fetal IVS was visualized successfully in 150 (99.3%) cases by real-time 3D echocardiography with live xPlane imaging, including 82 (54.3%) cases with the spine posterior and 68 (45.7%) cases with the spine anterior. The in-plane view of the IVS successfully visualized the VSDs in three fetuses with VSD and displayed the intact IVS in one fetus with transposition of the great arteries without VSD.

CONCLUSION

We describe live xPlane imaging, a simple method for the real-time assessment of the in-plane view of the IVS that has the potential to enhance the diagnostic accuracy of fetal cardiac examination.

Application of the 3-vessel view in routine prenatal sonographic screening for congenital heart disease

OBJECTIVES

The purpose of this study was to evaluate the diagnostic accuracy of prenatal screening for congenital heart disease (CHD) based on a combination of the 4-chamber view and 3-vessel view in an unselected population.

METHODS

A prospective study on 8025 scanned fetuses was performed. All singleton pregnancies scheduled for routine prenatal sonographic screening at 20 to 24 weeks' gestation and subsequently delivered in our unit were included. Data were recorded regarding visualization of the 4-chamber view, outflow tracts, and 3-vessel view. Suspected CHD was confirmed by postmortem or postnatal echocardiography. We obtained follow-up data for the neonates and calculated the diagnostic accuracy of the examinations.

RESULTS

Major CHD was identified in 32 cases (4.0%), of which 26 (81.3%) were diagnosed antenatally and 6 (18.7%) postnatally. Four cases (0.5%) had false-positive findings. Twenty-one cases were identified by the 4-chamber view and 5 by an abnormal 3-vessel view. The sensitivity of the 4-chamber view alone was 65.6%, and the specificity was 99.9%. The sensitivity of the combination of the 4-chamber view and 3-vessel view was 81.3%, and the specificity was 99.9%.

CONCLUSIONS

The 3-vessel view is a reliable and easy method to be used in a routine antenatal clinic along with the 4-chamber view.

Four-dimensional fetal echocardiography with spatiotemporal image correlation (STIC): A systematic study of standard cardiac views assessed by different observers

OBJECTIVE

To test the agreement between observers and reproducibility of a technique to display standard cardiac views of the left and right ventricular outflow tracts from four-dimensional volume datasets acquired with Spatiotemporal Image Correlation (STIC).

METHODS

A technique was developed to obtain dynamic multiplanar images of the left ventricular outflow tract (LVOT) and right ventricular outflow tract (RVOT) from volume datasets acquired with STIC. Volume datasets were acquired from fetuses with normal cardiac anatomy. Twenty volume datasets of satisfactory quality were pre-selected by one investigator. The data was randomly assigned for a blinded review by two independent observers with previous experience in fetal echocardiography. Only one volume dataset was used for each fetus. After a training session, the observers obtained standardized cardiac views of the LVOT and RVOT, which were scored on a scale of 1 to 5, based on diagnostic value and image quality (1=unacceptable, 2=marginal, 3=acceptable, 4=good, and 5=excellent). Median scores and interquartile range, as well as inter- and intraobserver agreement were calculated for each view.

RESULTS

The mean menstrual age at the time of volume acquisition was 25.5+/-4.5 weeks. Median scores (interquartile range) for LVOT images, obtained by the first and second observers, were 3.5 (2.25-5.00) and 4 (3.00-5.00), respectively. The median scores (interquartile range) for RVOT images obtained by the first and second observers were 3 (3.00-5.00) and 3 (2.00-4.00), respectively. The interobserver intraclass correlation coefficient for the LVOT was 0.693 (95% CI 0.380-0.822), and 0.696 (95% CI 0.382-0.866) for the RVOT. For the intraobserver agreement analysis, observer 1 gave higher scores to the LVOT the second time the volumes were analyzed [LVOT: 3.50 (2.25-5.00) vs. 5.00 (4.00-5.00, p=0.008)].

CONCLUSION

STIC can be reproducibly used to evaluate fetal cardiac outflow tracts by independent examiners. Slightly better image quality rating scores during the intraobserver variability trial suggests the presence of a learning curve for the manipulation and analysis of volume data obtained by STIC.

Prenatal detection of congenital heart disease

OBJECTIVES

To define current frequency of prenatal detection of congenital heart disease (CHD), factors affecting prenatal detection, and its influence on postnatal course.

STUDY DESIGN

We prospectively identified all fetuses and infants < or =6 months of age with major CHD at 3 referral centers in Northern California over 1 year; we obtained prenatal and demographic data, reviewed prenatal ultrasound (US) and postnatal records, and used logistic regression to analyze maternal, fetal, and prenatal-care provider risk factors for prenatal diagnosis.

RESULTS

Ninety-eight of 309 infants with major CHD had prenatal diagnosis (36% accounting for 27 pregnancy terminations); 185 infant-families participated in the postnatal survey, and although 99% had prenatal US, only 28% were prenatally diagnosed. Anomalous pulmonary venous return (0%), transposition of the great arteries (19%), and left obstructive lesions (23%) had the lowest prenatal detection. Heterotaxy (82%), single ventricle (64%), and HLHS (61%) had the highest. Prenatal diagnosis was higher at university versus community practices (P = .001). Sociodemographics were not associated with prenatal diagnosis. Infants diagnosed prenatally were less frequently ventilated (P < .01) or treated with prostaglandin (P < .05).

CONCLUSIONS

Prenatal detection of major CHD significantly alters postnatal course but remains low despite nearly universal US. CHD type and US practice type are important determinants of prenatal detection.