Prenatal detection of critical cardiac outflow tract anomalies remains suboptimal despite revised obstetrical imaging guidelines

Obstetric imaging practice characteristics associated with prenatal detection of critical congenital heart disease in a rural US region over 20 years

OBJECTIVE

To identify clinical practice characteristics associated with the frequency of prenatal critical congenital heart disease (CCHD) detection (i.e., the number of liveborn infants with postnatally confirmed CCHD identified on prenatal sonography) over 20 years in a rural setting comprised of 11 primarily low-volume obstetric hospitals and the single tertiary academic hospital to which they refer.

METHODS

This was a retrospective cohort study of all patients in the referral region with an initial prenatal and/or postnatal diagnosis of CCHD from 01/01/2002 to 12/31/2021. The frequency of prenatal CCHD detection at the time of an obstetric ultrasound was reported, as was the change in detection over time. Critical congenital heart disease detection was assessed as a function of cardiac lesion type, practice setting, and practice characteristics.

RESULTS

There were 271 cases with a confirmed postnatal CCHD diagnosis, of which 49% were identified prenatally. The majority of community practices each averaged <10 CCHD cases in total over the study period. Prenatal detection at the tertiary academic hospital's obstetric ultrasound unit was 64%, compared to 22% at the combined referring community practices (p < 0.001), though CCHD detection improved over time in both settings. Professional accreditation by the American Institute of Ultrasound in Medicine, image interpretation by radiology or Maternal Fetal Medicine, and use of video clips of ventricular outflow tracts were associated with improved prenatal CCHD detection.

CONCLUSIONS

Our data demonstrate the infrequency of CCHD cases at small-volume, rural hospitals and the substantial variation in prenatal CCHD detection across practice settings. Our methods allowed for the identification of practice characteristics associated with prenatal CCHD detection.

Geospatial Distribution of Prenatally and Postnatally Diagnosed Congenital Heart Disease: Implications for Equitable Care from a Fetal Heart Society Research Collaborative Study

OBJECTIVE

To characterize patterns in the geospatial distribution of pre- and postnatally diagnosed congenital heart disease (CHD) across 6 surgical centers.

STUDY DESIGN

A retrospective, multicenter case series from the Fetal Heart Society identified patients at 6 centers from 2012 through 2016 with prenatally (PrND) or postnatally (PoND) diagnosed hypoplastic left heart syndrome (HLHS) or d-transposition of the great arteries (TGA). Geospatial analysis for clustering was done by the average nearest neighbor (ANN) tool or optimized hot spot tool, depending on spatial unit and data type. Both point location and county case rate per 10 000 live births were assessed for geographic clustering or dispersion.

RESULTS

Of the 453 CHD cases, 26% were PoND (n = 117), and 74% were PrND (n = 336). PrND cases, in all but one center, displayed significant geographic clustering by the ANN. Conversely, PoND cases tended toward geographic dispersion. Dispersion of PoND HLHS occurred in 2 centers (ANN = 1.59, P < .001; and 1.47, P = .016), and PoND TGA occurred in 2 centers (ANN = 1.22, P < .05; and ANN = 1.73, P < .001). Hot spot analysis of all CHD cases (TGA and HLHS combined) revealed clustering near areas of high population density and the tertiary surgical center. Hot spot analysis of county-level case rate, accounting for population density, found variable clustering patterns.

CONCLUSION

Geographic dispersion among postnatally detected CHD highlights the need for a wider reach of prenatal cardiac diagnosis tailored to the specific needs of a community. Geospatial analysis can support centers in improving the equitable delivery of prenatal care.

Untangling the Complex Associations between Socioeconomic and Demographic Characteristics and Prenatal Detection and Outcomes in Congenital Heart Disease

Recent literature has established a strong foundation examining the associations between socioeconomic/demographic characteristics and outcomes for congenital heart disease. These associations are found beginning in fetal life and influence rates of prenatal detection, access to timely and appropriate delivery room and neonatal interventions, and surgical and other early childhood outcomes. This review takes a broad look at the existing literature and identifies gaps in the current body of research, particularly as it pertains to disparities in the prenatal detection of congenital heart disease within the United States. It also proposes further research and interventions to address these health disparities.

Truncus arteriosus from prenatal diagnosis to clinical outcome: a single-centre experience

BACKGROUND

The aim of this study was to review our institution's experience with truncus arteriosus from prenatal diagnosis to clinical outcome.

METHODS

and results: We conducted a single-centre retrospective cohort study for the years 2005-2020. Truncus arteriosus antenatal echocardiographic diagnostic accuracy within our institution was 92.3%. After antenatal diagnosis, five parents (31%) decided to terminate the pregnancy. After inclusion from referring hospitals, 16 patients were offered surgery and were available for follow-up. Right ventricle-to-pulmonary artery continuity was preferably established without the use of a valve (direct connection), which was possible in 14 patients (88%). There was no early or late mortality. Reinterventions were performed in half of the patients at latest follow-up (median follow-up of 5.4 years). At a median age of 5.5 years, 13 out of 14 patients were still without right ventricle-to-pulmonary artery valve, which was well tolerated without signs of right heart failure. The right ventricle demonstrated preserved systolic function as expressed by tricuspid annular plane systolic excursion z-score (-1.4 ± 1.7) and fractional area change (44 ± 12%). The dimensions and function of the left ventricle were normal at latest follow-up (ejection fraction 64.4 ± 6.2%, fractional shortening 34.3 ± 4.3%).

CONCLUSIONS

This study demonstrates good prenatal diagnostic accuracy of truncus arteriosus. There was no mortality and favourable clinical outcomes at mid-term follow-up, with little interventions on the right ventricle-to-pulmonary artery connection and no right ventricle deterioration. This supports the notion that current perspectives of patients with truncus arteriosus are good, in contrast to the poor historic outcome series. This insight can be used in counselling and surgical decision-making.

Navigating the spectrum of double-outlet right ventricle presentations: Outcomes from a contemporary cohort based on subtypes

PURPOSE

Our aim in this study was to investigate the prenatal and postnatal prognosis of double outlet right ventricle (DORV) cases diagnosed prenatally by analyzing the outcomes based on the subtype.

METHODS

This study is a retrospective chart review. Cases diagnosed with fetal DORV by prenatal ultrasound in the maternal-fetal medicine department of our hospital between 2014 and 2022 were included. Data on maternal characteristics, fetal echocardiographic features (type of DORV), pregnancy and neonatal outcomes (termination of pregnancy [TOP], intrauterine fetal death [IUD], neonatal death [NND], death in infancy (IND), survival) were collected and analyzed.

RESULTS

Ninety-nine cases of prenatally diagnosed cases of DORV were included. The prenatal diagnosis was right in 97% of the liveborn fetuses. The cases were classified into subtypes, including transposition of great arteries (TGA), Fallot, ventricular septal defect (VSD), remote, and heterotaxy types. The cohort consisted of 32.3% TGA type, 19.1% fallot type, 11.1% VSD type, 2% remote type, and 35.3% heterotaxy type of DORV. An additional cardiac anomaly was observed in 87% and an extra-cardiac anomaly was observed in 54% of the cases. When we excluded the cases with heterotaxy type but without any chromosomal abnormality, additional genetic abnormalities were detected in 42% of the remaining cases. Outcome of pregnancy was livebirth in 68/99 (68.7%), IUFD in 5/99 (5.1%), and TOP in 26/99 (26.3%). Postnatal cardiac surgical repair was performed in 48 cases. Survival among livebirths was 39/68 (57.3%). Twenty-nine neonates or infants who had additional cardiac anomalies and/or genetic abnormalities died before any surgical intervention. The postoperative survival rate was 39/48 (81.2%).

CONCLUSION

The prognosis in DORV depends on the anatomical subtype, the presence, and severity of associated anomalies. Survival increases in isolated cases without any additional structural or genetic anomalies.

Patient-reported barriers to prenatal diagnosis of congenital heart defects: A mixed-methods study

OBJECTIVE

To ascertain patient-reported, modifiable barriers to prenatal diagnosis of congenital heart defects (CHDs).

METHODS

This was a mixed-methods study among caretakers of infants who received congenital heart surgery from 2019 to 2020 in the Chicagoland area. Quantitative variables measuring sociodemographic characteristics and prenatal care utilization, and qualitative data pertaining to patient-reported barriers to prenatal diagnosis were collected from electronic health records and semi-structured phone surveys. Thematic analysis was performed using a convergent parallel approach.

RESULTS

In total, 160 caretakers completed the survey, 438 were eligible for survey, and 49 (31%) received prenatal care during the COVID-19 pandemic. When comparing respondents and non-respondents, there was a lower prevalence of maternal Hispanic ethnicity and a higher prevalence of non-English/Spanish-speaking households. Of all respondents, 34% reported an undetected CHD on ultrasound or echocardiogram, while 79% reported at least one barrier to prenatal diagnosis related to social determinants of health. Among those social barriers, the most common were difficulty with appointment scheduling (n = 12, 9.5%), far distance to care/lack of access to transportation (n = 12, 9.5%) and difficulty getting time off work to attend appointments (n = 6, 4.8%). The latter two barriers were correlated.

CONCLUSION

While technical improvements in the detection of CHDs remain an important area of research, it is equally critical to produce evidence for interventions that mitigate barriers to prenatal diagnosis due to social determinants of health.

The Left Outflow Tract in Fetal Cardiac Screening Examination: Introduction of Quality Criteria Is Not Always Associated With an Improvement of Practice When Supervised by Humans

OBJECTIVES

Since 2016, the French CNEOF included the left ventricular outflow tract (LVOT) in the second and third trimester of pregnancy in addition to the four-chamber view and the parasagittal view of the right outflow tract. The objective of this study was to define quality criteria for fetal LVOT assessment and to perform a human audit of past and current practices, before and after the implementation of those quality criteria at a large scale.

METHODS

Seven quality criteria were investigated and rated from 0 to 1 during three periods of interest. Files were randomly selected from three centers, and average total and specific scores were calculated.

RESULTS

LVOT pictures were present in more than 94.3% of reports. The average quality score was 5.49/7 (95% confidence interval [CI]: 5.36-5.62), 5.91/7 (95% CI: 5.80-6.03), and 5.70/7 (95% CI: 5.58-5.82) for the three centers in the three periods of interest. There was no significant difference following the introduction of the quality criteria, 2017 versus 2020, P = .054.

CONCLUSION

Fetal LVOT images were present in most of ultrasound reports but the introduction of the proposed quality criteria under human supervision seems not associated with a significant change in practice.

Prenatal Diagnosis Rate of Critical Congenital Heart Disease Remains Inadequate with Significant Racial/Ethnic and Socioeconomic Disparities and Technical Barriers

Prenatal diagnosis (preDx) of critical congenital heart disease (CCHD) decreases neonatal morbidity and mortality. Obstetrical fetal cardiac imaging guidelines in 2013 aimed to increase preDx. The objectives of this study were to determine the contemporary preDx rate of CCHD and identify maternal-fetal factors and variations in prenatal care that may be potential barriers. This retrospective single center study evaluated maternal demographics and characteristics of infants with CCHD (requiring cardiac catheterization or surgical intervention before 6 months-old) between 2016 and 2019. 58% of the 339 infants with CCHD had preDx. Infants with preDx were more likely to have mothers ≥ 35 years-old (p = 0.028), family history of CHD (p = 0.017), health insurance (p = 0.002), or anatomic scan with perinatology (p < 0.001). Hispanic infants were less likely to have preDx (45.6%, p = 0.005). PreDx rates were higher in infants with extracardiac/genetic anomalies (p < 0.001) and significantly different between CCHD subtypes (76% for single ventricle, 51% for biventricular/four-chamber view, 59% for proximal outflow tract anomalies, and 48% for distal great artery anomalies; p = 0.024). In infants without preDx, 25% of their mothers had indication for, but did not undergo, fetal echocardiography. PreDx rates of CCHD remains inadequate across subtypes detectable by standard fetal cardiac screening views, particularly in uninsured and Hispanic communities.

Prenatal detection of congenital heart disease: Recent experience across the state of Arizona

OBJECTIVE

To determine the prenatal detection rate (PDR) of congenital heart disease (CHD) in Arizona as well as describe various factors that may influence detection rates.

METHODS

This was a retrospective chart review using the Society of Thoracic Surgeons and Phoenix Children's Fetal Cardiology databases. We included all cases of CHD requiring surgery <1 year of age between 2013 and 2018. A total of 1137 patients met the criteria, and various demographic, socioeconomic, and patient outcome data were collected.

RESULTS

The overall PDR was 58% with an improving detection rate over the course of our study, with the final year having a PDR of 67%. Over time, PDR improved in urban communities, but this was not seen in rural communities. Rural address, public insurance, and Native American ethnicity were associated with lower PDR. Postnatal outcomes, including Apgars, initial pH, and lactate, did not differ with the presence of a prenatal diagnosis. Diagnoses typically identified with the outflow tract and 3-vessel views on the fetal echocardiogram were less likely to be detected prenatally.

CONCLUSIONS

The PDR of CHD continues to improve with evolving technologies and guidelines. We highlight a discrepancy between urban, rural, and Native American populations. Additionally, by supplying descriptors of missed diagnosis and associated echocardiography views, we hope to provide data for future interventions.

Artificial intelligence in cardiovascular diseases: diagnostic and therapeutic perspectives

Artificial intelligence (AI), the technique of extracting information from complex database using sophisticated computer algorithms, has incorporated itself in medical field. AI techniques have shown the potential to accelerate the progression of diagnosis and treatment of cardiovascular diseases (CVDs), including heart failure, atrial fibrillation, valvular heart disease, hypertrophic cardiomyopathy, congenital heart disease and so on. In clinical scenario, AI have been proved to apply well in CVD diagnosis, enhance effectiveness of auxiliary tools, disease stratification and typing, and outcome prediction. Deeply developed to capture subtle connections from massive amounts of healthcare data, recent AI algorithms are expected to handle even more complex tasks than traditional methods. The aim of this review is to introduce current applications of AI in CVDs, which may allow clinicians who have limited expertise of computer science to better understand the frontier of the subject and put AI algorithms into clinical practice.

How Automated Techniques Ease Functional Assessment of the Fetal Heart: Applicability of MPI+™ for Direct Quantification of the Modified Myocardial Performance Index

(1) Objectives: In utero functional cardiac assessments using echocardiography have become increasingly important. The myocardial performance index (MPI, Tei index) is currently used to evaluate fetal cardiac anatomy, hemodynamics and function. An ultrasound examination is highly examiner-dependent, and training is of enormous significance in terms of proper application and subsequent interpretation. Future experts will progressively be guided by applications of artificial intelligence, on whose algorithms prenatal diagnostics will rely on increasingly. The objective of this study was to demonstrate the feasibility of whether less experienced operators might benefit from an automated tool of MPI quantification in the clinical routine. (2) Methods: In this study, a total of 85 unselected, normal, singleton, second- and third-trimester fetuses with normofrequent heart rates were examined by a targeted ultrasound. The modified right ventricular MPI (RV-Mod-MPI) was measured, both by a beginner and an expert. A calculation was performed semiautomatically using a Samsung Hera W10 ultrasound system (MPI+™, Samsung Healthcare, Gangwon-do, South Korea) by taking separate recordings of the right ventricle's in- and outflow using a conventional pulsed-wave Doppler. The measured RV-Mod-MPI values were assigned to gestational age. The data were compared between the beginner and the expert using a Bland-Altman plot to test the agreement between both operators, and the intraclass correlation was calculated. (3) Results: The mean maternal age was 32 years (19 to 42 years), and the mean maternal pre-pregnancy body mass index was 24.85 kg/m² (ranging from 17.11 to 44.08 kg/m²). The mean gestational age was 24.44 weeks (ranging from 19.29 to 36.43 weeks). The averaged RV-Mod-MPI value of the beginner was 0.513 ± 0.09, and that of the expert was 0.501 ± 0.08. Between the beginner and the expert, the measured RV-Mod-MPI values indicated a similar distribution. The statistical analysis showed a Bland-Altman bias of 0.01136 (95% limits of agreement from -0.1674 to 0.1902). The intraclass correlation coefficient was 0.624 (95% confidence interval from 0.423 to 0.755). (4) Conclusions: For experts as well as for beginners, the RV-Mod-MPI is an excellent diagnostic tool for the assessment of fetal cardiac function. It is a time-saving procedure, offers an intuitive user interface and is easy to learn. There is no additional effort required to measure the RV-Mod-MPI. In times of reduced resources, such assisted systems of fast value acquisition represent clear added value. The establishment of the automated measurement of the RV-Mod-MPI in clinical routine should be the next level in cardiac function assessment.

Trends in Delayed Diagnosis of Critical Congenital Heart Defects in an Era of Enhanced Screening, 2004-2018

OBJECTIVE

To describe trends in delayed diagnosis of critical congenital heart defects (CCHDs) with prenatal and postnatal screening advances.

STUDY DESIGN

We evaluated a retrospective cohort of live births with CCHD delivered between 2004 and 2018 from a statewide, population-based birth defects surveillance system in Massachusetts. Demographic information were obtained from vital records. We estimated timely (prenatal or birth/transfer hospital) and delayed diagnosis (after discharge) proportions by year and time periods coinciding with the transition to mandatory pulse oximetry in 2015.

RESULTS

We identified 1524 eligible CCHD cases among 1 087 027 live births. By 2018, 92% of cases received a timely diagnosis, most prenatally. From 2004 to 2018, prenatal diagnosis increased from 46% to 76% of cases, while hospital diagnosis decreased from 38% to 17%, and delayed diagnosis declined from 16% to 7%. These trends were consistent across all characteristics evaluated. Among cases without a prenatal diagnosis, the proportion with delayed diagnosis did not change over time, even after implementation of mandatory pulse oximetry screening. Prenatal detection increased the most among severe cases (treated or died in first month of life). Well-appearing newborns without prenatal diagnosis made up 79% of delayed diagnosis cases by 2015-2018. Delayed diagnosis was most common for coarctation.

CONCLUSIONS

While prenatal diagnosis of CCHD increased dramatically, there was no reduction in delayed diagnosis among postnatally diagnosed infants, even after pulse oximetry screening became mandatory. Pulse oximetry may not reduce delayed diagnosis in settings with high prenatal detection, and other strategies are needed to ensure timely diagnosis of well-appearing newborns.

Coarctation of the aorta: Prenatal assessment, postnatal management and neonatal outcomes

Coarctation of the aorta (Coa) is a potentially life threatening diagnosis. It occurs in 0.3 per 1000 live births and accounts for 6-8% of all infants with congenital heart defects. Neonates with severe Coa may be completely asymptomatic at birth, as the ductus arteriosus can provide flow to the lower body. Those who are not diagnosed prenatally may be diagnosed only after constriction of the ductus arteriosus, when they present in cardiogenic shock. This group has a higher risk for mortality and morbidity relative to those diagnosed prenatally. Despite the increasing practice of universal pulse oximetry screening, many cases with significant coarctation of the aorta still go undiagnosed in the newborn period. In this article, we present the pathophysiology, diagnosis, presentation, treatment and outcomes of Coa.

Cyanosis in a Newborn Immediately after Birth

Cyanosis in a Newborn Immediately after BirthA male neonate, weighing 3.9 kg, was delivered via Cesarean section at 39 weeks of gestation. He cried immediately after birth, but his whole body appeared blue and he had low muscle tone that did not improve with suctioning and stimulation. Blow-by with 100% oxygen was initiated, and pulse oximetry on his left hand measured 40%. What is the diagnosis?

Geographic Distribution of Congenital Heart Disease: A Single Surgical Center Experience

OBJECTIVE

To determine presence of spatial clustering or dispersion of pre and postnatally detected hypoplastic left heart syndrome (HLHS) and d-transposition of the great arteries (TGA) cases.

STUDY DESIGN

This retrospective study examined all patients with a prenatal or postnatal diagnosis of HLHS or TGA who had an initial visit or hospitalization at our tertiary care center over a 5-year period from 2012 to 2016 (n = 105). Using geographic information systems software, the nearest neighbor ratio (NNR) tool was used to determine whether statistically significant clustering or dispersion occurred.

RESULTS

Geographic clustering was observed among prenatally diagnosed pooled cases of HLHS and TGA and all total cases (NNR = 0.73 and 0.66, respectively), but not postnatally detected cases (NNR = 1.08). Notably, there was significant dispersion of postnatally detected TGA cases (NNR = 1.22) There was no pattern for prenatally detected TGA or HLHS when analyzed individually.

CONCLUSIONS

The spatial distribution of HLHS and TGA is not random; these conditions occur in geographic clusters. Clustering of all patients in the study population and dispersion of postnatal diagnosis of TGA represent opportunities for improved delivery of fetal cardiac care.

The Mathematical Limitations of Fetal Echocardiography as a Screening Tool in the Setting of a Normal Second-Trimester Ultrasound

Background

The effectiveness of screening strategies targeting pregnancies at higher risk of congenital heart disease (CHD) is reduced by the low prevalence of severe CHD, the increase in CHD detection rates by second-trimester ultrasound (U/S), and the high proportion of severe CHD in low-risk pregnancies. We aimed to determine situations in which additional screening by fetal echocardiography (FE) would result in a significant increase in sensitivity and a sizable decrease in the false-negative rate of detection of severe CHD.

Methods

We simulated the change in the numbers of detected severe CHD cases when FE is offered to women with a normal second-trimester U/S who have a higher risk of bearing a child with CHD, compared to U/S alone. The primary outcome was the increase in sensitivity. Secondary outcomes were the number needed to screen and the reduction in the rate of missed cases.

Results

For an U/S sensitivity of 60%, the addition of FE in pregnancies at high risk of CHD (risk ratio 3.5; range: 2 to 5) increased sensitivity by 2.4 percentage points (1.1 to 7.9). The number needed to screen to detect one additional case of severe CHD was 436 (156 to 952). The rate of additional severe CHD cases detected by FE was 4 per 100,000 pregnancies (2 to 32).

Conclusions

The addition of FE to U/S for severe CHD prenatal screening in pregnancies at high risk of CHD yielded marginal benefits in terms of increased sensitivity and decreased rates of false negatives, at the expense of significant resource utilization.

Initial national investigation of the prenatal diagnosis of congenital heart malformations in Japan-Regional Detection Rate and Emergency Transfer from 2013 to 2017

BACKGROUND

Investigation into the detection rate (DR) of congenital heart diseases (CHDs) in fetuses is important for the assessment of fetal cardiac screening systems.

OBJECTIVES

We highlight issues of fetal cardiac screening in Japan.

METHODS

We performed an initial national survey of fetal diagnosis of CHDs from the data of the national registry for congenital heart surgery from 2013 to 2017. Subjects were neonates and infants with moderate or severe CHDs. We investigated DR in each prefecture in Japan and emergency transfer (ET) for neonates by analyzing distance and admission day of ET with or without fetal diagnoses.

RESULTS

The overall average DR in Japan was 0.41 (0.02 increase every year). No regional significant relationship was found between DR and population in each prefecture. ET was performed in 12% of neonates with prenatal diagnosis and in 63% of neonates without resulting in significant risk for ET in fetuses without a fetal diagnosis [OR 13.3 (11.6-15.3), p<0.001]. The distance of ET was shorter and admission was earlier in the neonates with a prenatal diagnosis than in those without [median 6.6 km (IQR: 4.1-25.7) vs 17.0 km (IQR: 7.4-35.3), median 0.0 day (IQR: 0.0-0.0) vs 0.0 day (IQR: 0.0-1.0), p<0.001, p<0.001, respectively] CONCLUSIONS: Prenatal cardiac diagnosis reduces geographic and chronological risks of ET for moderate to severe CHDs. DR is still developing and periodic official surveillance is required for improving prenatal cardiac diagnosis in Japan.

Prenatal diagnosis of congenital heart defects: echocardiography

Congenital heart defects (CHD) are the most common congenital anomaly, and the majority can be diagnosed during prenatal life. Prenatal detection rates remain highly variable, as most CHD occur in low risk pregnancies and therefore depend on the maternal obstetric provider to recognize fetal cardiac abnormality on obstetric screening anatomic ultrasound. Fetuses with abnormal findings on obstetric screening anatomic ultrasound and/or risk factors for cardiac disease should be referred for evaluation with fetal echocardiography. Fetal echocardiography should be performed by specialized sonographers and interpreted by physicians with knowledge of evolving fetal cardiac anatomy and physiology throughout gestation. A fetal echocardiography examination, which can be done from the late first trimester onward, utilizes a standardized and systemic approach to diagnose fetuses with CHD or other forms of primary or secondary cardiac disease. The field of fetal cardiology has advanced past the accurate prenatal diagnosis of simple and complex CHD, as fetal echocardiography enables understanding of dynamic fetal cardiac physiology and consideration of potential fetal/neonatal treatment. The greatest impact of fetal echocardiography remains identification of critical CHD before birth to allow immediate cardiac management after delivery to decrease neonatal morbidity and mortality. Analyzing the severity of abnormal cardiac physiology in various forms of CHD before birth allows the fetal cardiologist to prognosticate effects on the developing fetus, predict risk of postnatal hemodynamic instability, guide delivery planning through multidisciplinary collaboration, and anticipate how the disease will impact the neonate after delivery.

A 'holistic' sonographic view on congenital heart disease - How automatic reconstruction using fetal intelligent navigation echocardiography (FINE) eases the unveiling of abnormal cardiac anatomy part I: Right heart anomalies

Attempting a comprehensive examination of the fetal heart remains challenging for unexperienced operators as it emphasizes the acquisition and documentation of sequential cross-sectional and sagittal views and inevitably results in diminished detection rates of fetuses affected by congenital heart disease. The introduction of four-dimensional spatio-temporal image correlation (4D STIC) technology facilitated a volumetric approach for thorough cardiac anatomic evaluation by the acquisition of cardiac 4D datasets. By analyzing and re-arranging of numerous frames according to their temporal event within the heart cycle, STIC allows visualization of cardiac structures as an endless cine loop sequence of a complete single cardiac cycle in motion. However, post-analysis with manipulation and repeated slicing of the volume usually requires experience and in-depth anatomic knowledge, which limits the widespread application of this advanced technique in clinical care and unfortunately leads to the underestimation of its diagnostic value to date. Fetal intelligent navigation echocardiography (FINE), a novel method that automatically generates and displays nine standard fetal echocardiographic views in normal hearts, has shown to be able to overcome these limitations. Very recent data on the detection of congenital heart defects (CHDs) using the FINE method revealed a high sensitivity and specificity of 98% and 93%, respectively. In this two-part manuscript, we focused on the performance of FINE in delineating abnormal anatomy of typical right and left heart lesions and thereby emphasized the educational potential of this technology for more than just teaching purposes. We further discussed recent findings in a pathophysiological and/or functional context.

Impact of Socioeconomic Status, Race and Ethnicity, and Geography on Prenatal Detection of Hypoplastic Left Heart Syndrome and Transposition of the Great Arteries

BACKGROUND

Prenatal detection (PND) has benefits for infants with hypoplastic left heart syndrome (HLHS) and transposition of the great arteries (TGA), but associations between sociodemographic and geographic factors with PND have not been sufficiently explored. This study evaluated whether socioeconomic quartile (SEQ), public insurance, race and ethnicity, rural residence, and distance of residence (distance and driving time from a cardiac surgical center) are associated with the PND or timing of PND, with a secondary aim to analyze differences between the United States and Canada.

METHODS

In this retrospective cohort study, fetuses and infants <2 months of age with HLHS or TGA admitted between 2012 and 2016 to participating Fetal Heart Society Research Collaborative institutions in the United States and Canada were included. SEQ, rural residence, and distance of residence were derived using maternal census tract from the maternal address at first visit. Subjects were assigned a SEQ z score using the neighborhood summary score or Canadian Chan index and separated into quartiles. Insurance type and self-reported race and ethnicity were obtained from medical charts. We evaluated associations among SEQ, insurance type, race and ethnicity, rural residence, and distance of residence with PND of HLHS and TGA (aggregate and individually) using bivariate analysis with adjusted associations for confounding variables and cluster analysis for centers.

RESULTS

Data on 1862 subjects (HLHS: n=1171, 92% PND; TGA: n=691, 58% PND) were submitted by 21 centers (19 in the United States). In the United States, lower SEQ was associated with lower PND in HLHS and TGA, with the strongest association in the lower SEQ of pregnancies with fetal TGA (quartile 1, 0.78 [95% CI, 0.64-0.85], quartile 2, 0.77 [95% CI, 0.64-0.93], quartile 3, 0.83 [95% CI, 0.69-1.00], quartile 4, reference). Hispanic ethnicity (relative risk, 0.85 [95% CI, 0.72-0.99]) and rural residence (relative risk, 0.78 [95% CI, 0.64-0.95]) were also associated with lower PND in TGA. Lower SEQ was associated with later PND overall; in the United States, rural residence and public insurance were also associated with later PND.

CONCLUSIONS

We demonstrate that lower SEQ, Hispanic ethnicity, and rural residence are associated with decreased PND for TGA, with lower SEQ also being associated with decreased PND for HLHS. Future work to increase PND should be considered in these specific populations.

An ensemble of neural networks provides expert-level prenatal detection of complex congenital heart disease

Congenital heart disease (CHD) is the most common birth defect. Fetal screening ultrasound provides five views of the heart that together can detect 90% of complex CHD, but in practice, sensitivity is as low as 30%. Here, using 107,823 images from 1,326 retrospective echocardiograms and screening ultrasounds from 18- to 24-week fetuses, we trained an ensemble of neural networks to identify recommended cardiac views and distinguish between normal hearts and complex CHD. We also used segmentation models to calculate standard fetal cardiothoracic measurements. In an internal test set of 4,108 fetal surveys (0.9% CHD, >4.4 million images), the model achieved an area under the curve (AUC) of 0.99, 95% sensitivity (95% confidence interval (CI), 84-99%), 96% specificity (95% CI, 95-97%) and 100% negative predictive value in distinguishing normal from abnormal hearts. Model sensitivity was comparable to that of clinicians and remained robust on outside-hospital and lower-quality images. The model's decisions were based on clinically relevant features. Cardiac measurements correlated with reported measures for normal and abnormal hearts. Applied to guideline-recommended imaging, ensemble learning models could significantly improve detection of fetal CHD, a critical and global diagnostic challenge.

Fetal Echocardiography for the General Pediatrician

Fetal echocardiography is now commonly used to assess fetuses for congenital heart disease. To care for their patients, it is important for the pediatrician to understand the utility of the test, the benefits, and the limitations of the results. This review outlines the indications, components, and limitations of fetal echocardiography with a focus on the care that the pediatrician provides to newborns and their families. An understanding of the fetal cardiac examination can assist the pediatrician in caring for patients with either normal or abnormal test results. The need for and timing of postnatal cardiology follow-up, and guidance on referral for fetal echocardiogram for future pregnancies are all critical roles that the pediatrician can play. Most importantly, an understanding of the limitations, including difficult-to-diagnose lesions, allows the pediatrician to maintain a high level of suspicion for cardiac defects regardless of fetal echocardiography findings. [Pediatr Ann. 2021;50(3):e121-e127.].

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.

Low prenatal detection rate of valvar pulmonary stenosis: What are we missing?

OBJECTIVES

Critical pulmonary stenosis (PS) and pulmonary atresia with intact ventricular septum (PAIVS) require urgent neonatal intervention. Since PS may be more insidious than PAIVS during gestation, we hypothesized that neonates with PS would have lower rates of prenatal detection than PAIVS.

METHODS

We performed a retrospective chart review of all neonates who underwent diagnostic or interventional cardiac catheterization between 2000 and 2014 for critical PS or PAIVS. The rates of prenatal diagnosis were calculated for PS and PAIVS. Prenatal and postnatal echocardiographic data were reviewed.

RESULTS

178 patients met inclusion criteria: 91 with critical PS and 87 with PAIVS. The prenatal diagnosis rate for critical PS was lower than for PAIVS at 37% (34/91) vs 60% (52/87) (P = .003). At the time of diagnosis at a median gestational age of 25 weeks, the median TV z-score for patients with critical PS was larger than in PAIVS (-0.15 vs -3.0 P = .004).

CONCLUSION

Critical PS had a lower prenatal detection rate than PAIVS, likely due to a relatively normal 4-chamber view at the time of routine second trimester screening in patients with PS. Color flow Doppler of the outflow tracts may improve detection, since outflow tracts may appear normal by 2D imaging.

The Use of Sonography in a Mother and Fetus With Concordant Truncus Arteriosus

Reported pregnancies in women with repaired truncus arteriosus are rare. As a result of improved surgical techniques, more women with conotruncal defects are now reaching reproductive age. Multifactorial inheritance rather than single gene mutation is the causative agent of most congenital heart disease. The environment can play an important and varied role in direct transmission, particularly in incidences where genes predispose a defect. This may be one of the first reported cases discussing a pregnant mother with repaired truncus arteriosus and her fetus, prenatally diagnosed with a concordant truncal defect.

Integrative Perinatal Management Enhanced the Advantage of Prenatal Diagnosis on Critical Pulmonary Valve Stenosis: An Observational Preliminary Study

Background: Percutaneous balloon valvuloplasty (PBPV) is recommended as a first-choice treatment for critical pulmonary stenosis (CPS). A concept of perinatal integrative management has been developed. Unfortunately, the evidence on the advantage of integrative management for CPS during the perinatal period is absent. Methods: Single-center, observational, preliminary research has been developed, and three groups have been enrolled. There were 42 children with CPS enrolled for this study between January 2014 and December 2017 in our center, and their follow-up duration is at least 1 year. Three groups were set up: the integrative perinatal management group (group I), who received prenatal diagnosis with perinatal management to maintain circulation and an optimized PBPV procedure; the prenatal diagnosis group (group PR), who received a diagnosis of pulmonary stenosis before birth without any monitoring and perinatal management; and the postnatal diagnosis group (group PO), who received the CPS diagnosis after birth. Result: There were 13 patients enrolled in group I, 11 babies enrolled in group PR, and 18 cases included in group PO. Integrative management helped to put the timing of PBPV in advance. The age for PBPV in group I was 9.38 ± 5.58 days, and groups PR and PO were 24.54 ± 4.87 and 49.11 ± 9.50 days, respectively. The average peak transvalvular gradient (PGs) of the perinatal management group (group I) and prenatal diagnosis group (group PR) remained at a stable level. However, the average PGs of group PO were progressively elevated during follow-up. Moreover, the follow-up data from group I revealed an advantage in RV development and functional restoration. There was no difference among the three groups in the ratio of reintervention and postoperative moderate pulmonary regurgitation during 1-year follow-up (p >0.05). Conclusion: Prenatal diagnosis helps to improve the outcomes of PBPV. Moreover, perinatal integrative medical management enhances the advantage of prenatal diagnosis. However, this research is still a small-size cohort study, and the limited population number and follow-up duration were the major limitations to expand the conclusions.

Prenatal diagnosis of congenital heart defects: experience of the first Fetal Cardiology Unit in Mexico

OBJECTIVE

The purpose of this article was to describe our experience with the prenatal diagnosis of CHD in patients referred to our Fetal Cardiology Unit.

METHODS

Prospective cohort study of consecutive fetuses referred for advanced fetal echocardiography to our Fetal Cardiology Unit during a 3-year period (September 2015-September 2018).

RESULTS

Totally 809 fetuses were evaluated, with 1263 fetal advanced echocardiographies performed. Suspected cardiac abnormality was the most common indication for referral (62.2%). Only 7.3% of patients had known morbidities or risk factors for CHD. Mean gestational age at first examination was 25.6 ± 6.4 weeks. A total of 528 (65.3%) fetuses were found to have a cardiac defect: 40.7% had isolated CHD while 24.6% had associated anomalies. The most common defects found were ventricular septal defects (20.3%), followed by conotruncal defects (9.7%), hypoplastic left heart syndrome (9.3%), fetal arrhythmias (8.9%), and venous anomalies (8.7%). 31.6% presented abnormal genetic studies, the most frequent being Down syndrome (23/212, 10.8%), followed by DiGeorge syndrome (11/212, 5.2%).

CONCLUSIONS

Prenatal screening and diagnosis of CHD in Mexico are feasible, with suspected cardiac abnormality being the main reason for referral to a specialized Fetal Cardiology Unit. Efforts must be made to make screening available to the general population in the first and second trimesters of pregnancy by fetal medicine or trained specialists, in order to identify fetal CHD and offer advanced echocardiography, genetic studies, timely fetal cardiac intervention in selected cases, and delivery in tertiary centers, to improve overall survival.

[The left outflow tract: Normal features]

Congenital heart disease remains an important cause of perinatal morbidity and mortality. Screening for these is based on a good knowledge of normal fetal heart anatomy and ultrasound views to be performed. After recommending the use of the four chambers and the right outflow tract views in 2005, CNEOF proposes recently adding the left outflow tract assessment. The use of this one should sensitize the operator to the notion of sweeping essential to obtain all these views and make it possible to improve the detection of the conal VSD and conotruncal pathologies.