Fetal echocardiography at 11-13 weeks by transabdominal high-frequency ultrasound

Evaluation of first-trimester ultrasound screening strategy for fetal congenital heart disease

OBJECTIVE

To assess the performance of a standardized first-trimester ultrasound screening strategy for fetal congenital heart disease (CHD).

METHODS

This was a large retrospective study involving 74 839 consecutive mixed-risk pregnancies (77 396 fetuses). Routine ultrasound scans at 11 + 0 to 13 + 6 weeks' gestation were performed in a single center from January 2015 to June 2023. All fetuses were examined using a predefined standardized ultrasound scanning strategy with adjustment of imaging parameters, which included assessment of the fetal heart. The ultrasound results (e.g. extracardiac congenital malformations), ultrasound markers (e.g. nuchal translucency thickening, reversed a-wave in the ductus venosus and tricuspid regurgitation), follow-up, genetic tests and diagnostic results were recorded and analyzed.

RESULTS

In total, there were 831 cases of CHD, with an incidence of 1.07% (831/77 396). In the first-trimester scan, 590 fetuses were diagnosed with CHD, but four were confirmed as normal in later examinations. In addition, 245 cases were missed. The detection rate was 70.52%, with a sensitivity, specificity, false-positive rate and false-negative rate of 70.52%, 99.99%, 0.01% and 29.48%, respectively. In fetuses with negative ultrasound markers and no extracardiac malformations, the detection rate of CHD was 45.79% (185/404). There were 281 cases that underwent karyotyping and chromosomal microarray (245 fetuses) or whole-exome sequencing (36 fetuses). In total, 38.79% (109/281) had a positive genetic test result. There were 273/831 CHD cases associated with extracardiac malformations. The abnormal image patterns and abnormal features of each view in the scanning strategy were summarized.

CONCLUSIONS

Ultrasound screening for fetal CHD in the first trimester of pregnancy enables earlier prenatal diagnosis and consultation. The standardized ultrasound screening strategy used in this study had a high detection rate for fetal CHD in the first trimester. Our proposed fetal heart screening strategy shows promising effectiveness for early diagnosis of CHD and we recommend its use. It is important to note, however, that first-trimester ultrasound screening for fetal CHD should not replace fetal echocardiography in the second trimester. © 2025 International Society of Ultrasound in Obstetrics and Gynecology.

Study on ultrasound diagnosis and pathological anatomy of fetal complex congenital heart disease in the first trimester

PURPOSE

To assess the feasibility of using the stereo-microscope to identify the pathological anatomy of the congenital heart diseases in the first trimester.

METHODS

Fifteen fetuses of 8-12 weeks aborted due to prevent miscarriage failure and 42 fetuses of 11-14 weeks with congenital heart diseases were included in the study, we dissected their hearts through a stereo-microscope, then compared with the prenatal ultrasonographic diagnosis.

RESULTS

Using stereomicroscopy, the positive view of the heart and the great arteries, the long axis view of the aortic arch, the inflow tract view of the bottom heart, the semilunar valve view of the bottom heart, and the transverse section of the ventricle were showed contented and obtained satisfactory images, but the structure of atrioventricular valve and venous system had a lower rate of display.

CONCLUSION

The characteristic pathological changes of cardiac inflow and outflow tract can be obtained by dissecting the heart sequential under the stereo-microscopy. However it is often difficult to obtain satisfactory pathological sections for pulmonary venous abnormalities and Ebstein anomaly.

Learning Curve of First-Trimester Detailed Cardiovascular Ultrasound Screening by Moderately Experienced Obstetricians in 3509 Consecutive Unselected Pregnancies with Fetal Follow-Up

Our primary objective was to assess the effectiveness of detailed cardiovascular ultrasound screening during the first trimester, which was performed by obstetricians with intermediate experience. We collected first-trimester fetal cardiac screening data from an unselected pregnant population at RMC-Fetal Medicine Center during a study period spanning from 1 January 2010, to 31 January 2015, in order to analyze our learning curve. A pediatric cardiologist performed a follow-up assessment in cases where the examining obstetrician determined that the fetal cardiac screening results were abnormal or high-risk. Overall, 42 (0.88%) congenital heart abnormalities were discovered prenatally out of 4769 fetuses from 4602 pregnant women who had at least one first-trimester cardiac ultrasonography screening. In total, 89.2% of the major congenital heart abnormalities (27 of 28) in the following fetuses were discovered (or at least highly suspected) at the first-trimester screening and subsequent fetal echocardiography by the pediatric cardiology specialist. Of these, 96.4% were diagnosed prenatally. According to our results, the effectiveness of first-trimester fetal cardiovascular ultrasound screening conducted by moderately experienced obstetricians in an unselected ('routine') pregnant population may reach as high as 90% in terms of major congenital heart defects, provided that equipment, quality assurance, and motivation are appropriate.

False-Positive Diagnosis of Congenital Heart Defects at First-Trimester Ultrasound: An Italian Multicentric Study

Objective. Our objective was to assess the proportion of false-positive CHD cases at the first-trimester evaluation of the fetal heart, performed by experienced operators. Methods. This multicenter retrospective study included of pregnant women with suspicion of CHDs during first-trimester screening for aneuploidies. In all cases, the fetal heart assessments were performed by obstetricians with extensive experience in first-trimester scanning, following an extended protocol proposed by SIEOG national guidelines, which included an axial view of the fetal abdomen and chest to assess visceral situs and evaluation of the four-chamber view (4CV) and three-vessel trachea view (3VTV) with color Doppler. In all suspected cases, fetal echocardiography was offered within 16 and/or at 19-22 weeks' gestation. Results. From a population of 4300 fetuses, 46 CHDs were suspected. Twenty-four cases were excluded from this analysis because the parents opted for early termination of the pregnancies due to associated structural and/or genetic anomalies. For the remaining 22, echocardiography was performed by 16 weeks in 14 cases (64%) and after 16 weeks in 8 cases. In 19 cases (86.4%), a fetal cardiologist confirmed the presence of a CHD. In three cases (13%), the cardiac anatomy was found to be normal at the fetal echocardiography and postnatally. Conclusions. This study shows that the proportion of false-positive cases at the first-trimester ultrasound examination of the fetal heart, performed by experienced operators, may carry a higher risk of false-positive diagnosis than expected. Therefore, this issue must be discussed in instances where a CHD is suspected at the first-trimester screening.

Clinical implementation of first trimester screening for congenital heart defects

OBJECTIVE

To examine the feasibility and performance of implementing a standardized fetal cardiac scan at the time of a routine first-trimester ultrasound scan.

METHOD

A retrospective, single-center study in an unselected population between March 2021 and July 2022. A standardized cardiac scan protocol consisting of a four-chamber and 3-vessel trachea view with color Doppler was implemented as part of the routine first-trimester scan. Sonographers were asked to categorize the fetal heart anatomy. Data were stratified into two groups based on the possibility of evaluating the fetal heart. The influence of maternal and fetal characteristics and the detection of major congenital heart disease were investigated.

RESULTS

A total of 5083 fetuses were included. The fetal heart evaluation was completed in 84.9%. The proportion of successful scans increased throughout the study period from 76% in the first month to 92% in the last month. High maternal body mass index and early gestational age at scan significantly decreased the feasibility. The first-trimester detection of major congenital heart defects was 7/16, of which four cases were identified by the cardiac scan protocol with no false-positive cases.

CONCLUSION

First-trimester evaluation of the fetal heart by a standardized scan protocol is feasible to implement in daily practice. It can contribute to the earlier detection of congenital heart defects at a very low false positive rate.

Pregnancy Termination and Postnatal Major Congenital Heart Defect Prevalence After Introduction of Prenatal Cardiac Screening

Importance

Prenatal cardiac screening of the first and second trimesters has had a major impact on postnatal prevalence of congenital heart defects (CHDs), rates of termination of pregnancy (TOP), and outcomes among children born alive with CHDs.

Objective

To examine the prenatal and postnatal incidence of major CHDs (ie, necessitating intervention within the first year of life), detection rate trends, rates of TOP, and the association of cardiac screening with postnatal outcomes.

Design, Settings, and Participants

In this cross-sectional study, 3827 fetuses with antenatally diagnosed major CHDs in the Czech Republic (population 10.7 million) between 1991 and 2021 were prospectively evaluated with known outcomes and associated comorbidities. Prenatal and postnatal prevalence of CHD in an unselected population was assessed by comparison with a retrospective analysis of all children born alive with major CHDs in the same period (5454 children), using national data registry. Data analysis was conducted from January 1991 to December 2021.

Main Outcomes and Measures

Prenatal detection and postnatal prevalence of major CHDs and rate of TOPs in a setting with a centralized health care system over 31 years.

Results

A total of 3 300 068 children were born alive during the study period. Major CHD was diagnosed in 3827 fetuses, of whom 1646 (43.0%) were born, 2069 (54.1%) resulted in TOP, and 112 (2.9%) died prenatally. The prenatal detection rate increased from 6.2% in 1991 to 82.8% in 2021 (P < .001). Termination of pregnancy decreased from 70% in 1991 to 43% (P < .001) in 2021. Of 627 fetuses diagnosed in the first trimester (introduced in 2007), 460 were terminated (73.3%). Since 2007, of 2066 fetuses diagnosed in the second trimester, 880 (42.6%) were terminated, resulting in an odds ratio of 3.6 (95% CI, 2.8-4.6; P < .001) for TOP in the first trimester compared with the second trimester. Postnatal prevalence of major CHDs declined from 0.21% to 0.14% (P < .001). The total incidence (combining prenatal detection of terminated fetuses with postnatal prevalence) of major CHD remained at 0.23% during the study period.

Conclusions and Relevance

In this cross-sectional study, the total incidence of major CHD did not change significantly during the 31-year study period. The prenatal detection of major CHD approached 83% in the current era. Postnatal prevalence of major CHD decreased significantly due to early TOPs and intrauterine deaths. The introduction of first trimester screening resulted in a higher termination rate in the first trimester but did not revert the overall decreasing trend of termination for CHDs in general.

Four-section approach of fetal congenital heart disease at 11-13+6 weeks

Objective

The objective of the study is to explore the value of the four-section approach in detecting fetal heart defects in the first trimester (11-13+6 weeks), analyze the reasons for the inconsistency between the results of ultrasound examination in the first trimester and subsequent verification, and describe the most common abnormal flow patterns of four sections.

Materials and methods

Between June 2019 and June 2021, a prenatal four-section approach (upper abdominal transverse section, four-chamber section, three vessel-trachea section, and bilateral subclavian artery section) with verification results in early pregnancy was analyzed.

Results

In total, 9,533 fetuses were included. Finally, 176 fetuses with congenital heart disease (CHD), containing 34 types, were identified. The total detection rate of cardiac abnormalities was 1.85%. 102 cases were accurately diagnosed by ultrasonography during early pregnancy. A total of 74 fetuses who had inconsistent results between fetal cardiac ultrasound and verification in early pregnancy were reported, of which the cases of 22 fetuses were inconsistent due to disease evolution and progression and the cases of 52 fetuses were inconsistent due to missed diagnosis and misdiagnosis. The sensitivity, specificity, positive predictive value, and negative predictive value of the four-section approach were 67.05%, 99.96%, 96.58%, and 99.33%, respectively. In this study, a total of 30 abnormal ultrasonic imaging patterns in four sections were summarized.

Conclusion

We confirmed that the four-section approach in early pregnancy has a good diagnostic efficacy for fetal CHD. Intrauterine evolution of the fetal heart, missed diagnosis, and misdiagnosis are the reasons for the inconsistency between the results of early pregnancy ultrasound and subsequent verification. This study also presents the abnormal imaging patterns of four scan sections of CHD in early pregnancy, which are instructive for the rapid identification and diagnosis of CHD in the first trimester.

Evaluation fetal heart in the first and second trimester: Results and limitations

Background

Cardiac heart defects affect nearly 6-12 per 1000 live births in the general population and are more frequent than common trisomies.

Aim

To assess the efficacy and technical limitations of first-trimester fetal heart evaluation in the 11-14^th-weeks' scan and comparison with the second-trimester anatomical exam by ultrasound.

Material and Method

Between April 2015 and July 2020, medical records and ultrasound data of 3295 pregnancies who underwent first-trimester fetal anatomy exams by ultrasound were reviewed retrospectively. All ultrasound exams were performed by the same two operators (TUKD, OP) with transabdominal transducers. Fetal situs, four-chamber view, outflow tracts, and three-vessel trachea view are the cornerstones of first-trimester fetal heart examination. Conventional grayscale mode and high-definition power Doppler mode were utilized. The same operators re-examined all cases between the 18 and 23 weeks of gestation by ISUOG guidelines.

Results

We performed a combined transvaginal and transabdominal approach for only 101 cases (3.06%). The mean maternal age was 31.28 ± 4.43, the median gestational age at the first-trimester ultrasound exam was 12.4 weeks, and the median CRL was 61.87 mm (range was 45.1-84 mm). Even combined approach situs, cardiac axis, and four-chamber view could not be visualized optimally in 28 cases (0.7%). Outflow tracts were visualized separately in 80% (2636 in 3295) cases. Three vessel-trachea views were obtained in 85.4% (2814 in 3295) cases by high-definition Doppler mode. There were 47 fetuses with cardiac defects in 3295 pregnancies with the known pregnancy outcome. Ten cases had abnormal karyotype results. Thirty-two fetuses with cardiac anomalies (9.7 in 1000 pregnancies) were detected in the first-trimester examination, and the remaining 15 (4.55 in 1000 pregnancies) cases were diagnosed in the second-trimester examination. The prevalence of congenital cardiac anomalies was 14.25 in 1000 pregnancies. Fifteen cases were missed in the first-trimester exam. Also, ten fetuses which had abnormal cardiac findings in the first-trimester exam were not confirmed in the second-trimester exam. Sensitivity, specificity, positive, and negative predictive values were calculated as 65.3%, 99.7%, 66.8%, and 99.67%, respectively.

Conclusion

Late first-trimester examination of the fetus is feasible and allows earlier detection of many structural abnormalities of the fetus, including congenital heart defects. Suspicious and isolated cardiac abnormal findings should be re-examined and confirmed in the second-trimester exam. Previous abdominal surgery, high BMI, and subtle cardiac defects can cause missed cardiac abnormalities.

Learning deep architectures for the interpretation of first-trimester fetal echocardiography (LIFE) - a study protocol for developing an automated intelligent decision support system for early fetal echocardiography

BACKGROUND

Congenital Heart Disease represents the most frequent fetal malformation. The lack of prenatal identification of congenital heart defects can have adverse consequences for the neonate, while a correct prenatal diagnosis of specific cardiac anomalies improves neonatal care neurologic and surgery outcomes. Sonographers perform prenatal diagnosis manually during the first or second-trimester scan, but the reported detection rates are low. This project's primary objective is to develop an Intelligent Decision Support System that uses two-dimensional video files of cardiac sweeps obtained during the standard first-trimester fetal echocardiography (FE) to signal the presence/absence of previously learned key features.

METHODS

The cross-sectional study will be divided into a training part of the machine learning approaches and the testing phase on previously unseen frames and eventually on actual video scans. Pregnant women in their 12-13 + 6 weeks of gestation admitted for routine first-trimester anomaly scan will be consecutively included in a two-year study, depending on the availability of the experienced sonographers in early fetal cardiac imaging involved in this research. The Data Science / IT department (DSIT) will process the key planes identified by the sonographers in the two- dimensional heart cine loop sweeps: four-chamber view, left and right ventricular outflow tracts, three vessels, and trachea view. The frames will be grouped into the classes representing the plane views, and then different state-of-the- art deep-learning (DL) pre-trained algorithms will be tested on the data set. The sonographers will validate all the intermediary findings at the frame level and the meaningfulness of the video labeling.

DISCUSSION

FE is feasible and efficient during the first trimester. Still, the continuous training process is impaired by the lack of specialists or their limited availability. Therefore, in our study design, the sonographer benefits from a second opinion provided by the developed software, which may be very helpful, especially if a more experienced colleague is unavailable. In addition, the software may be implemented on the ultrasound device so that the process could take place during the live examination.

TRIAL REGISTRATION

The study is registered under the name "Learning deep architectures for the Interpretation of Fetal Echocardiography (LIFE)", project number 408PED/2020, project code PN-III-P2-2.1-PED-2019.

TRIAL REGISTRATION

ClinicalTrials.gov , unique identifying number NCT05090306, date of registration 30.10.2020.

First Trimester Tricuspid Regurgitation: Clinical Significance

Tricuspid regurgitation is a cardiac valvular anomaly that consists of the return of blood to the right atrium during systole due to incomplete valve closure. This structure can be visualized on ultrasound between 11 and 14 weeks of gestation in most cases. Despite being a common finding, even in healthy fetuses, the presence of tricuspid regurgitation may be associated with chromosomal and structural abnormalities. The evaluation of tricuspid flow and the presence of regurgitation on first-trimester ultrasound has shown promising results regarding its role in the early detection of aneuploidies, congenital heart defects, and other adverse perinatal outcomes. This review article aims to demonstrate the importance of tricuspid regurgitation as a secondary marker, and consequently, significant benefits of its early detection when added to the combined first-trimester screening. Its value will be discussed, namely its sensitivity and specificity, alone and together with other current markers in the fetal assessment performed in the first-trimester ultrasound.

The impact of high-frequency linear transducer on the accuracy of pelvic ultrasound in early pregnancy pelvic pain and bleeding

INTRODUCTION

The primary concern of emergency physicians (EPs) in symptomatic patients in their early pregnancy is to rule out ectopic pregnancy by identifying a definite intrauterine pregnancy (IUP). Then an assessment of viability is required for the IUPs. Although transvaginal ultrasound (TVUS) stands as the best modality for these patients, it is not available in most emergency settings. This study aimed to investigate the effects of high-frequency linear transducers (HFLT) on the accuracy of point-of-care ultrasound (POCUS) for detection of IUP and the agreement between EPs and obstetricians for patients' diagnosis.

METHOD

A convenience sample of pregnant patients who presented to the emergency department (ED) with vaginal bleeding and abdominopelvic pain was included. The characteristics of diagnostic tests of transabdominal POCUS performed by EPs were compared to TVUS.

RESULTS

The study population was finalized as 143 patients. For the definite IUP, the diagnostic accuracy of POCUS was 93.0%, with a sensitivity of 89.0%, a specificity of 100%, compared to an accuracy of 97.9% for POCUS plus HFLT with a sensitivity of 96.7%, a specificity of 100%. For the identification of fetal cardiac activity (FCA), utilizing HFLT improved the diagnostic accuracy to 97.9% (from 94.4%) and sensitivity to 95.5% (from 88.1%). In addition, the agreement between the EPs and obstetricians concerning the classification of ED diagnosis was excellent (agreement: 96.5%, kappa: 0.943, p < 0.0001).

CONCLUSION

POCUS plus HFLT performed by EPs in evaluating symptomatic patients in their first-trimester pregnancy improves the accuracy to a non-inferior level compared to TVUS performed by obstetricians. Hence, EPs can securely rely on POCUS to confirm IUP and FCA. However, they should be cautious about using it as a rule-out tool. Moreover, HFLT use could enhance the accuracy of POCUS in viability assessment as an alternative to TVUS.

A Deep Learning Approach for the Assessment of Signal Quality of Non-Invasive Foetal Electrocardiography

Non-invasive foetal electrocardiography (NI-FECG) has become an important prenatal monitoring method in the hospital. However, due to its susceptibility to non-stationary noise sources and lack of robust extraction methods, the capture of high-quality NI-FECG remains a challenge. Recording waveforms of sufficient quality for clinical use typically requires human visual inspection of each recording. A Signal Quality Index (SQI) can help to automate this task but, contrary to adult ECG, work on SQIs for NI-FECG is sparse. In this paper, a multi-channel signal quality classifier for NI-FECG waveforms is presented. The model can be used during the capture of NI-FECG to assist technicians to record high-quality waveforms, which is currently a labour-intensive task. A Convolutional Neural Network (CNN) is trained to distinguish between NI-FECG segments of high and low quality. NI-FECG recordings with one maternal channel and three abdominal channels were collected from 100 subjects during a routine hospital screening (102.6 min of data). The model achieves an average 10-fold cross-validated AUC of 0.95 ± 0.02. The results show that the model can reliably assess the FECG signal quality on our dataset. The proposed model can improve the automated capture and analysis of NI-FECG as well as reduce technician labour time.

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.

Non-linear Methods Predominant in Fetal Heart Rate Analysis: A Systematic Review

The analysis of fetal heart rate variability has served as a scientific and diagnostic tool to quantify cardiac activity fluctuations, being good indicators of fetal well-being. Many mathematical analyses were proposed to evaluate fetal heart rate variability. We focused on non-linear analysis based on concepts of chaos, fractality, and complexity: entropies, compression, fractal analysis, and wavelets. These methods have been successfully applied in the signal processing phase and increase knowledge about cardiovascular dynamics in healthy and pathological fetuses. This review summarizes those methods and investigates how non-linear measures are related to each paper's research objectives. Of the 388 articles obtained in the PubMed/Medline database and of the 421 articles in the Web of Science database, 270 articles were included in the review after all exclusion criteria were applied. While approximate entropy is the most used method in classification papers, in signal processing, the most used non-linear method was Daubechies wavelets. The top five primary research objectives covered by the selected papers were detection of signal processing, hypoxia, maturation or gestational age, intrauterine growth restriction, and fetal distress. This review shows that non-linear indices can be used to assess numerous prenatal conditions. However, they are not yet applied in clinical practice due to some critical concerns. Some studies show that the combination of several linear and non-linear indices would be ideal for improving the analysis of the fetus's well-being. Future studies should narrow the research question so a meta-analysis could be performed, probing the indices' performance.

The diagnostic value of the early extended fetal heart examination at 13 to 14 weeks gestational age in a high-risk population

BACKGROUND

Congenital heart disease (CHD) is the most common congenital malformation that affects high-risk populations. A more definite heart diagnosis in the first trimester should be provided to guide clinical treatment. The study aim was to evaluate the diagnostic precision of the early extended fetal heart examination (EFHE) that includes abdominal situs view, four-chamber view (4CV), left ventricular outflow tract view (LVOT), right ventricular outflow tract view (RVOT), 3-vessel and tracheal view (3VT), ductal arch view, and the aortic arch view in the detection of CHD at the gestational age (GA) 13 to 14 weeks in a population with high risks.

METHODS

This study was a diagnostic test study. EFHE was performed by transabdominal sonography in women at GA 13 to 14 weeks with singleton pregnancies who were at high risk for CHD. The risk of CHD was determined by family history of CHD, rubella infection, metabolic disorders, exposure to teratogens, conception by in-vitro fertilization (IVF), increased nuchal translucency (NT) thickness, abnormal obstetric ultrasound, etc. The operator had more than 5 years of experience in first-trimester scans and fetal echocardiography. Early scans were compared with a fetal echocardiography in the second trimester (16-24 weeks).

RESULTS

EFHE was performed, and the pregnancy outcomes were obtained in 234 single pregnancies with a high risk of CHD. The average crown-rump length (CRL) was (76.17±7.09) mm. CHD was diagnosed in 43 cases by EFHE; 10 of these cases were misdiagnosed, and 2 cases were missed. Four cases were inconsistent in the main diagnosis of CHD. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and kappa coefficient (Ko) value of EFHE in diagnosing CHD by type and severity was 84.6% [95% confidence interval (CI), 69.5-94.1%], 96.9% (95% CI, 93.4-98.9%), 84.6% (95% CI, 69.5-94.1%), 96.9% (95% CI, 93.4-98.9%), and 0.82 (P<0.001), respectively.

CONCLUSIONS

EFHE can work as a diagnose examination for most major CHD cases at GA 13 to 14 weeks by an experienced operator; Therefore, this diagnostic system for fetal CHD may be applied in the first trimester. The study has been registered in the Chinese Clinical Trial Registry (www.chictr.org.cn). The registration number is ChiCTR2000038451.

Postmortem Micro-CT of Human Fetal Heart-A Systematic Literature Review

Micro-computed tomography (CT) is a non-invasive alternative to conventional macroscopic dissection for the evaluation of human fetal cardiac anatomy. This paper aims to systematically review the literature regarding the use of micro-CT to examine human fetal hearts, to illustrate its educational and research implications and to explain its possible directions for the future. A systematic literature review was conducted following the PRISMA statement to identify publications concerning micro-CT applications for the isolated human fetal heart. The search strategy identified nine eligible studies. Micro-CT is technically feasible for postmortem examination of the human fetal heart coming from early and late termination of pregnancy. It reaches high diagnostic accuracy, and it seems to perform better than autopsy in small samples or in the case of early termination of pregnancy. Applications derived from micro-CT allow multiple off-time evaluations and interdisciplinary comparisons for educational purposes and research perspectives in biological and bioengineering domains.

Prenatal incidence of isolated right aortic arch and double aortic arch

OBJECTIVE

To define the incidence of variants of aortic arch sidedness in fetuses undergoing routine first trimester ultrasound examination.

METHODS

The data for this study were derived from prospective routine ultrasound examination at 11+0 to 13+6 weeks' gestation in singleton pregnancies examined in a local population between January 2014 and March 2018. We examined the incidence of isolated right aortic arch (RAA) and double aortic arch (DAA) in the local, screened population and compared the groups with and without these abnormalities.

RESULTS

The study population of 33,202 pregnancies included 18 (5.4 per 10,000) cases with isolated RAA and 5 (1.5 per 10,000) with DAA. In the group with isolated RAA or DAA, compared to those without, the median maternal age was higher and the incidence of conceptions from in vitro fertilization (IVF) was eight-fold higher. The prevalence of 22q11microdeletion was 5% in patients with RAA from this local population.

CONCLUSIONS

The incidence of isolated RAA and DAA in a local population undergoing routine first-trimester ultrasound examination is 2-3-fold higher than that reported in postnatal studies and the risk for these abnormalities is substantially increased in fetuses conceived by IVF.

Ultrasound Patterns in the First Trimester Diagnosis of Congenital Heart Disease

Congenital heart disease (CHD) is the most common birth defect, with a reported prevalence of 5–12 per 1000 live births. Very recently, the American Institute of Ultrasound in Medicine published a guideline recommending the use of the four-chamber and the three-vessel and trachea views to screen for CHD in the first trimester of pregnancy. Our aim is to present abnormal image patterns that are seen in the four-chamber, three-vessel, and trachea views of the fetal heart in the first trimester and to describe their association with specific CHD types. We used a total of 29 cases of CHD from the archives of Filantropia Hospital and the Maternal and Child Health Institute (INSMC) fetal medicine units. We selected cases with a clear and well-documented diagnosis of the CHD type. We identified a series of repeating color doppler flow patterns seen in the four-chamber, three-vessel, and trachea views of the studied cases. Our observations could be developed into a diagnosis algorithm to orientate the examiner to the most likely type of CHD in individual cases.

Applications of Advanced Ultrasound Technology in Obstetrics

Over the years, there have been several improvements in ultrasound technologies including high-resolution ultrasonography, linear transducer, radiant flow, three-/four-dimensional (3D/4D) ultrasound, speckle tracking of the fetal heart, and artificial intelligence. The aims of this review are to evaluate the use of these advanced technologies in obstetrics in the midst of new guidelines on and new techniques of obstetric ultrasonography. In particular, whether these technologies can improve the diagnostic capability, functional analysis, workflow, and ergonomics of obstetric ultrasound examinations will be discussed.

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

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

Fetal Echocardiography Indications and Lack of Association between Abnormal Exams and Advanced Maternal Age: A Cross-Sectional Study - Fetal Abnormal Echocardiography

OBJECTIVE

 To analyze the most frequent referrals for fetal echocardiography, including advanced maternal age and its association with abnormal results.

METHODS

 We included all pregnant women referred to perform fetal echocardiography (gestational age 22-32 weeks) in 2 health centers in Rio de Janeiro, from June 2015 to June 2016. Advanced maternal age was considered when age was > 35 years at the time of delivery). Referral reasons and results were recorded, according to the Brazilian Fetal Cardiology Statement. Crude and adjusted prevalence ratios were calculated (Poisson regression). We considered p < 0.05 as significant.

RESULTS

 A total of 1,221 tests were analyzed. Abnormal fetal echocardiography was observed in 14.82% of the cases. The most frequent abnormalities were interventricular septal defect (6.39%), septal hypertrophy (3.35%) and atrioventricular septal defect (1.14%). Routine exams were performed in 559 women, 289 were referred for advanced maternal age and 373 were referred according to the Brazilian Fetal Cardiology Statement criteria. An obstetric ultrasound suggesting fetal cardiac abnormality, maternal diabetes, increased nuchal translucency, and obstetric ultrasound suggesting a noncardiac abnormality were strongly associated with an abnormal fetal echocardiography. Abnormal results were not more frequent in women with advanced maternal age when compared with the rest of the study group.

CONCLUSIONS

 It was observed that routine exams and advanced maternal age referrals were very frequent. Those exams were not associated to fetal echocardiography abnormalities. In this scenario, when the obstetric ultrasound suggests a fetal cardiac abnormality, the fetal echocardiography probably is abnormal. Therefore, obstetric ultrasound is a good screening method.

Tetralogy of Fallot and Outlet Ventricular Septal Defect with Anterior Malalignment Detected at Early Fetal Echocardiography

OBJECTIVES

To examine the evolution of tetralogy of Fallot (TOF) and outlet ventricular septal defect (VSD) with anterior malalignment (am) from the initial diagnosis at early fetal echocardiography through the gestation and to evaluate the impact of the first-trimester scan on the outcome.

METHODS

We identified cases of TOF or outlet VSD with am diagnosed before 16 weeks' gestation. For all cases, prenatal data and pregnancy outcomes were evaluated. In continuing pregnancies, the evolution in severity of the disease was assessed.

RESULTS

Fifty-one fetuses with TOF or outlet VSD with am were diagnosed at early fetal echocardiography. Parents opted for termination of pregnancy in all 23 cases associated with additional anomalies. In 2 of 28 continuing pregnancies, there was an intrauterine death. In the remaining 26, there was progression in severity in 7 (by 20-22 weeks in 3 cases and during the third trimester in the remaining 4).

CONCLUSIONS

TOF and outlet VSD with am diagnosed before 16 weeks' gestation can progress in severity throughout pregnancy in over one-quarter of cases. In addition, a high proportion of cases diagnosed in the first trimester may have associated extracardiac anomalies, with a significant impact on clinical management and on the rate of early termination of pregnancy.

Operator experience impact on the evaluation of still images of a first trimester cardiac assessment protocol

Objective: Congenital heart disease (CHD) is the most common birth defect and represents the leading cause for mortality and morbidity in infants and young adults. Early fetal echocardiography is usually considered a highly specialized scan. The goal of this study is to evaluate the impact of operator's experience in assessing still images of the 4-chamber view and 3-vessels view and to evaluate the feasibility and the performance of a first trimester screening protocol for CHD.Methods: An online questionnaire consisting of still images of the 4-camber view and 3-vessel view from 50 normal and abnormal cases was reviewed by an expert group made of seven obstetricians specialized in fetal medicine and a nonexpert group made of 13 obstetricians that are certified in ultrasound. After individually visualizing each image set made of the 4-chamber view and 3-vessel view, they had to conclude if the case was normal or abnormal and what images were abnormal.Results: A total of 50 image sets of both normal and abnormal fetal hearts were examined by the 20 reviewers, resulting in 1000 evaluations. The expert group achieved a detection rate of 97.1% with a false positive rate of 5.7%. The nonexpert group achieved also a good detection rate of 91.3% but with a much higher false positive rate of 33.9%. The most frequently missed CHD involved the great arteries and had a normal 4-chamber view. In the majority of false positive cases the 3-vessel view was incorrectly interpreted as abnormal.Conclusions: A screening protocol for CHD, based on the 4-chamber view and 3-vessel view alone can offer a good detection rate for CHD with a small false positive rate, but only if it is implemented by highly specialized sonographers.

Micro-computed tomography of isolated fetal hearts following termination of pregnancy: A feasibility study at 8 to 12 weeks' gestation

OBJECTIVES

To assess the feasibility of retrieval of intact human fetal hearts after first trimester surgical termination of pregnancy (TOP) and subsequent anatomical assessment by postmortem micro-computed tomography (micro-CT).

METHODS

In a cohort of consenting women undergoing surgical TOP between 8 and 13 weeks' gestation, we attempted the retrieval of the fetal heart from the suction material. Specimens were immersion fixed in 10% formaldehyde, scanned by iodine-enhanced micro-CT and cardiac anatomy assessed by a multidisciplinary team using 3D-multiplanar analysis.

RESULTS

The median gestational age at TOP was 10.7 weeks (range 8.3-12.9). In 57 (95.0%) out of 60 suction specimens, the heart could be retrieved. The median cardiac length was 5 mm (range 2-8 mm), in three (5.3%), the heart was too damaged to assess cardiac anatomy and in five (8.7%) only the four chambers could be examined. In the remaining 49 (86.0%) cases, a detailed assessment of cardiac anatomy was possible, showing a major defect in two (4.1%) and a minor defect in four (8.2%).

CONCLUSIONS

Fetal hearts can be retrieved after first trimester TOP being intact in the vast majority of cases. Iodine-enhanced, postmortem micro-CT can be used to assess cardiac anatomy from as early as 8 weeks and to describe heart abnormalities.

Performance of First-Trimester Fetal Echocardiography in Diagnosing Fetal Heart Defects: Meta-analysis and Systematic Review

OBJECTIVES

Early fetal echocardiography is becoming increasing common during the nuchal translucency scan period. The aim of this meta-analysis was to assess the accuracy of first-trimester fetal echocardiography in diagnosing congenital heart defects (CHDs).

METHODS

The databases of PubMed, Embase, the Cochrane Library, and the Cumulative Index to Nursing and Allied Health Literature were systematically searched for the candidate articles, and the references of included studies were also examined. We recorded the characteristics of the included studies and assessed the quality of each study by the Quality Assessment of Diagnostic Accuracy Studies tool. The pooled sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), diagnostic odds ratio (DOR), and area under the curve (AUC) were calculated with Meta-Disc version 1.4 software (Ramón y Cajal Hospital, Madrid, Spain). We also evaluated the publication bias by using Stata version 12.0 software (StataCorp, College Station, TX).

RESULTS

This meta-analysis included 18 studies with 26,201 fetal hearts. The overall pooled sensitivity, specificity, PLR, and NLR were 0.750, 0.999, 392.95, and 0.277, respectively. The DOR and AUC were 1736.0 and 0.9331. The pooled sensitivity, specificity, PLR, NLR, DOR, and AUC for major CHDs were 0.838, 1.000, 725.69, 0.203, 5084.8, and 0.9617.

CONCLUSIONS

First-trimester fetal echocardiography had high value in diagnosing CHDs, especially major CHDs.

Screening performance of congenital heart defects in first trimester using simple cardiac scan, nuchal translucency, abnormal ductus venosus blood flow and tricuspid regurgitation

OBJECTIVE

The objective of this study was to analyze if the addition of simple cardiac scan in cases with increased nuchal translucency (NT) and/or abnormal ductus venosus (DV) blood flow, and/or tricuspid regurgitation (TCR) can improve detection of congenital heart defects (CHD) in chromosomally normal fetuses without non-cardiac defects at 11-13 + 6 gestational weeks in a population of singleton pregnancies.

METHODS

During the 10 years period, all singleton pregnancies at 11-13 + 6 weeks were routinely scanned for NT, DV blood flow and TCR assessment and, if a single of these parameters was abnormal, simple cardiac scan with 2D gray scale and color and/or directional power Doppler in 4-chamber (4-CV) and 3 vessel and trachea views (3VTV) was performed.

RESULTS

The sensitivity and specificity of NT ≥ 95th + DV R/A a-wave + TCR in detecting CHD were 77% and 97%, respectively, and of simple cardiac scan, 67% and 98%, respectively. Area under the curve of receiver operating characteristic curve of NT ≥ 95th + DV R/A a-wave + TCR was 0.838, and of NT ≥ 95th + DV R/A a-wave + TCR + simple cardiac scan was 0.915.

CONCLUSIONS

In chromosomally normal fetuses without non-cardiac anomalies, addition of simple cardiac scan to the combined first trimester screening parameters improves detection of major CHD during first trimester.

Congenital fetal heart defect - an agreement between fetal echocardiography and autopsy findings

AIMS

To determine the frequency of pregnancy terminations due to prenatal congenital heart defect (CHD) and assess the agreement fetal echocardiography (FECHO) and autopsy findings.

METHODS

The data were retrospectively assessed between 2008 and 2017 in a population of 116 698 live births. The correlations between the FECHO and autopsy findings were classified into five levels of agreement: complete, partial, altered diagnosis, disagreement, and unfeasible autopsy.

RESULTS

Totally, 293 CHDs were identified and 49% of families (143/293) decided to terminate the pregnancy. In 1% (2/143) of cases, the autopsy could not be performed, for the other 99% (141/143), the pathologist confirmed the presence of CHDs. Complete agreement between FECHO and autopsy was achieved in 85% (122/143). In 10% (14/143) of cases, the pathologist found minor findings, which were not described in the FECHO. In 4% (5/143) of cases, the pathologist changed the main diagnosis.

CONCLUSION

Altogether, the results indicated that FECHO is a highly sensitive method for the prenatal detection of CHD but is incapable of detecting the complete spectrum of cardiac defects. Autopsies verified the diagnosis, confirmed the overall impairment in the fetus, and provided data for further counselling of the affected family.

Prenatal diagnosis and clinical implications of an apparently isolated right aortic arch

OBJECTIVE

To define the associations of a prenatally diagnosed, apparently isolated right aortic arch (RAA) with chromosomal or genetic abnormalities and tracheal compression.

METHODS

This was a retrospective study of apparently isolated RAA assessed by fetal cardiologists and fetal medicine specialists at Kings College Hospital, London between 2000 and 2017.

RESULTS

The search identified 138 cases of apparently isolated RAA. Invasive testing was performed in 75, and chromosomal or genetic anomalies were identified in 16 (22%), and the most common was 22q11 microdeletion. An aberrant left subclavian artery was seen in 51% of cases. Symptoms of a vascular ring were present in 24 of 97 (25%) children who were reviewed after birth. Bronchoscopy was performed in 33 children, and significant tracheal compression was diagnosed in 28, including 18 of 19 symptomatic and 10 of 14 asymptomatic children.

CONCLUSIONS

An apparently isolated RAA is associated with a high incidence of chromosomal or genetic abnormalities and a high incidence of tracheal compression in symptomatic and asymptomatic patients. Prenatal counselling for genetic associations and postnatal airway assessment in the context of the vascular anatomy is recommended.

The outcome of structural heart defects diagnosed in the first trimester of pregnancy

PURPOSE

We present the results of a detailed protocol of fetal heart examination in the first trimester, in a fetal medicine unit in Romania.

METHODS

Since October 2009, in Filantropia Hospital in Bucharest, we have systematically assessed pregnancies at 11-14 weeks to screen for aneuploidies and for major fetal structural defects. The fetal anatomy examination protocol included the detailed assessment of the fetal heart. This was performed using the same principles as for the second trimester examination, in the entire cohort.

RESULTS

Our population consisted of 7693 patients and 7816 embryos. The protocol for the ultrasound evaluation of the fetal heart was completed for 7597 embryos (97.2%). The outcome is known for 6912 cases (90.9%). We diagnosed 39 heart defects - 30 in the first trimester, seven in the second trimester, two postnatally. Twenty of the 39 heart defects were isolated cardiac malformations. Twelve of the isolated heart defects were diagnosed in the first trimester. The sensitivity of the first trimester ultrasound in identifying major heart defects was 76.92%. The overall survival in cases of isolated congenital heart disease diagnosed in the first trimester was significantly lower than the survival in the cases diagnosed in the second trimester.

CONCLUSIONS

Many (76.92%) of the significant heart defects can be diagnosed by ultrasound examination, in the first trimester. Our study is an argument for developing the multidisciplinary approach needed for the management of early detected structural heart disease.

Fetal heart rhabdomyomatosis: a single-center experience

Objectives: The primary aim of the study was to evaluate the prevalence of fetal heart tumors in a single tertiary referral center over a period of 15 years. The secondary aim was to confirm the presence of tuberous sclerosis complex (TSC) through the evaluation of germline mutation in TSC1/TSC2 and assess the outcomes in affected fetuses and newborns.Methods: A retrospective study was conducted between 2003 and 2017. Fetal echocardiography was performed in the second trimester of pregnancy in the study population. The identification of heart tumors and further follow-up were performed by a pediatric cardiologist. Molecular genetic analysis was conducted on fetuses and children in cases where TSC was suspected.Results: In total, 39,018 fetuses were examined between 2003 and 2017. Heart tumors were detected in nine fetuses and were diagnosed as rhabdomyoma in all cases. We identified mutations in one of the TSC1 or TSC2 genes in all cases with multiple rhabdomyomas (8/9). In all born children (5/9), the genetically confirmed diagnosis of TSC was established, and clinically pathological deposits in the brain were found.Conclusion: Fetal heart tumors are usually represented by rhabdomyomas having a good cardiac prognosis. However, rhabdomyoma is usually the first symptom of TSC with a subsequent brain disorder and impaired neurological development.

Fetal cardiac examination can affect patients' preference on invasive tests: A new data on maternal anxiety indicated karyotyping

BACKGROUND

Prenatal screening for aneuploidies has seen great changes over the last 2 decades. But there is still no non-invasive diagnostic test. Therefore, prenatal invasive procedures are still being routinely performed due to maternal anxiety. The association of cardiac anomalies and abnormal findings with aneuploidies has been known for a long time. This prospective study was done to evaluate abnormal fetal cardiac examination (FCE) findings on patients undergoing diagnostic invasive procedures due to maternal anxiety and to assess the predictive value of abnormal cardiac findings on abnormal karyotype.

MATERIALS AND METHODS

Patients who underwent prenatal diagnostic invasive tests due to maternal anxiety indication between March 2013 and September 2016 were included in this study. FCE was performed in the study group immediately prior to invasive tests. Findings of fetal cardiac examination are classified as normal, major-minor cardiac anomalies and soft markers. Fetal karyotypes were compared among groups depending on cardiac findings.

RESULTS

One hundred eighty-two invasive procedures were performed because of maternal anxiety during this period. There were 29 abnormal findings detected on FCE. A total of 7 abnormal karyotypes were detected. FCE was abnormal in 5 of the abnormal karyotypes (71.4%). The presence of a major cardiac anomaly was most predictive for abnormal karyotype (LR+: 96,67, LR-: 0,34). No association was detected between the presence of minor cardiac anomalies and abnormal karyotype. Normal FCE appeared to be a good predictive factor for normal karyotype (LR-: 0.20).

CONCLUSIONS

This is the first study evaluating the power of early fetal cardiac examination findings on fetal aneuploidies. This study suggested that the application of fetal cardiac examination findings to genetic counseling for screening aneuploidies may be efficient on patients' preference about invasive tests. Due to the small number of abnormal findings and karyotypes detected (not the large study group), further studies on large study groups are needed to confirm these results.

Non-Adaptive Methods for Fetal ECG Signal Processing: A Review and Appraisal

Fetal electrocardiography is among the most promising methods of modern electronic fetal monitoring. However, before they can be fully deployed in the clinical practice as a gold standard, the challenges associated with the signal quality must be solved. During the last two decades, a great amount of articles dealing with improving the quality of the fetal electrocardiogram signal acquired from the abdominal recordings have been introduced. This article aims to present an extensive literature survey of different non-adaptive signal processing methods applied for fetal electrocardiogram extraction and enhancement. It is limiting that a different non-adaptive method works well for each type of signal, but independent component analysis, principal component analysis and wavelet transforms are the most commonly published methods of signal processing and have good accuracy and speed of algorithms.

Diagnosis of Fetal Structural Anomalies at 11 to 14 Weeks

OBJECTIVES

To assess the performance of first-trimester ultrasound (US) in identifying major fetal structural abnormalities in an unselected population.

METHODS

We conducted a retrospective analysis of all pregnancies that underwent the 11- to 14-week scan in the Fetal Medicine Department of Filantropia Hospital in Bucharest, which were prospectively examined within our screening program. The purpose of the first-trimester US was to evaluate the risk for chromosomal abnormalities and to conduct fetal anatomic examination using a detailed protocol.

RESULTS

Our population consisted of 7480 pregnant patients (7576 fetuses). The follow-up was completed for 6045 patients (6114 fetuses). The prevalence of major structural anomalies was 1.89%. In the first trimester, we identified 79% of all major structural anomalies. The highest detection rates were achieved for abdominal wall defects (100%), major central nervous system anomalies (88%), cardiac defects (74%), and skeletal anomalies (71%). The nuchal translucency was increased in 35% of the cases with structural anomalies, and 95% of these were diagnosed in the first trimester. Seventy percent of the patients who presented with structural anomalies and a normal nuchal translucency were diagnosed in the first trimester.

CONCLUSIONS

Our results emphasize the importance of performing a detailed US examination at 11 to 14 weeks' gestation in identification of fetal structural defects.

Echocardiographic Methods of Fetal Heart Size Assessmentheart to Chest Area Ratio and Transversal Heart Diameter

Introduction: Ultrasound assessment of fetal heart size (FHS) is widely used and recommended in many guidelines of fetal echocardiography due to its clinical value. The aim of this study was an analysis of some fetal heart measurements: ratio of heart area to chest area (HA/ CA) and transversal diameter of heart (AP) and their correlation to gestational age.

Material and methods: This retrospective study was based on database of records of ultrasound and echocardiographic examinations performed in our unit and included fetuses between 15th and 39th week of gestation with no evidence of heart defect or any abnormality.

Results: 609 ultrasound examinations were analyzed. The mean HA/CA was 0,30 ± 0,015, with no statistical difference between female and male (p>0,05), and seemed to be relatively constant with slight increase with advancing gestational age. The AP diameter in whole group correlated with gestational age (r=0,94) and there was no difference related to the fetuses gender.

Conclusion: The correlation of AP diameter and relative constancy of HA/CA ratio with gestational age presented in our normograms could be used for monitoring fetal development, but also for fetal cardiomegaly assessment.

Does First-Trimester Screening Modify the Natural History of Congenital Heart Disease?

Background:

The study analyzed the impact of first-trimester screening on the spectrum of congenital heart defects (CHDs) later in pregnancy and on the outcome of fetuses and children born alive with a CHD.

Methods:

The spectrum of CHDs, associated comorbidities, and outcome of fetuses, either diagnosed with a CHD in the first trimester (Group I, 127 fetuses) or only in the second-trimester screening (Group II, 344 fetuses), were analyzed retrospectively between 2007 and 2013. Second-trimester fetuses diagnosed with a CHD between 2007 and 2013 were also compared with Group III (532 fetuses diagnosed with a CHD in the second trimester from 1996 to 2001, the period before first-trimester screening was introduced).

Results:

The spectrum of CHDs diagnosed in the first and second trimesters in the same time period differed significantly, with a greater number of comorbidities ( P <0.0001), CHDs with univentricular outcome ( P <0.0001), intrauterine deaths ( P =0.01), and terminations of pregnancy ( P <0.0001) in Group I compared with Group II. In Group III, significantly more cases of CHDs with univentricular outcome ( P <0.0001), intrauterine demise ( P =0.036), and early termination ( P <0.0001) were identified compared with fetuses diagnosed with CHDs in the second trimester between 2007 and 2013. The spectrum of CHDs seen in the second-trimester groups differed after first-trimester screening was implemented.

Conclusions:

First-trimester screening had a significant impact on the spectrum of CHDs and the outcomes of pregnancies with CHDs diagnosed in the second trimester. Early detection of severe forms of CHDs and significant comorbidities resulted in an increased pregnancy termination rate in the first trimester.

The Performance of First-Trimester Anatomy Scan: A Decision Analysis

Introduction First-trimester ultrasound (US) for anatomy assessment may improve anomaly detection, but it may also increase overall US utilization. We sought to assess the utility of first-trimester US for evaluation of fetal anatomy. Materials and Methods A decision analytic model was created to compare first- plus second-trimester anatomy scans to second-trimester scan alone in four populations: general, normal weight women, obese women, and diabetics. Probability estimates were obtained from the literature. Outcomes considered were number of: major structural anomalies detected, US performed, and false-positive US. Multivariable sensitivity analyses were performed to evaluate the consistency of the model with varying assumptions. Results A strategy of first- plus second-trimester US detected the highest number of anomalies but required more US examinations per anomaly detected. The addition of a first-trimester anatomy US was associated with a small increase in the false-positive US (< 10/10,000). In populations with higher anomaly prevalence and lower second-trimester US sensitivity (i.e., diabetes, obesity), the number of additional US performed per anomaly detected with the first-trimester US was < 60. Discussion In high-risk populations, a first-trimester US in addition to a second-trimester US may be a beneficial approach to detecting anomalies.

Screening performances of abnormal first-trimester ductus venosus blood flow and increased nuchal translucency thickness in detection of major heart defects

OBJECTIVE

The aim of this study was to evaluate the screening performances of abnormal ductus venosus (DV) blood flow for the detection of heart defects in chromosomally normal fetuses with increased nuchal translucency (NT) thickness at 11-13 + 6 weeks' gestational in a population of singleton pregnancies.

METHODS

During an 8-year period, all singleton pregnancies from 11 + 0 to 13 + 6 weeks were scanned for NT and DV blood flow assessment. Two groups of cases with abnormal NT were evaluated: NT ≥ 95th and NT ≥ 99th centile. DV waveforms were considered to be abnormal if the a-wave was reversed or absent (R/A).

RESULTS

Addition of DV R/A a-wave to either NT ≥ 95th or NT ≥ 99th percentile increased specificity (p < 0.001 and p < 0.001, respectively), but not screening performances in detection of major heart defects (p = 0.73 and p = 0.91, respectively). Combination of DV R/A a-wave with NT ≥ 95th or NT ≥ 99th centile correlated with right heart defects (p = 0.024 and p = 0.013, respectively).

CONCLUSIONS

In chromosomally normal fetuses, addition of abnormal DV a-wave to increased NT does not improve screening performances of NT in detection of major hearts defects in first trimester. However, there is correlation of such parameter with right heart defects and AV septal defects.

Diagnostic Value of Fetal Echocardiography for Congenital Heart Disease: A Systematic Review and Meta-Analysis

Prenatal diagnosis of fetal congenital heart disease (CHD) has been shown to have a significant effect on prenatal and postnatal management and outcomes. However, the factors influencing the diagnostic accuracy and which pregnant trimester is the most adaptive for fetal heart disease remain uncertain despite of extensive researches. The aim of the present study was to evaluate the accuracy of echocardiography for detecting CHD and potential influence factors.We searched Chinese Biomedical Database (CBM), Medline, ISI Web of Knowledge, the Cochrane Library, and China National Knowledge Infrastructure (CNKI) to identify relevant studies from January 1, 1990 to August 13, 2015.Overall, the pooled sensitivity, specificity, diagnostic odds ratio, positive likelihood ratio, and negative likelihood ratio were 68.5% (95% confidence interval [CI], 66.8%-70.2%), 99.8% (95% CI, 99.7%-99.8%), 3026.9 (95% CI, 1417.9-6461.8), 659.41 (95% CI, 346.38-1255.3), and 0.246 (95% CI, 0.187-0.324) respectively (AUC = 0.9924). The pooled sensitivity of basic cardiac echocardiographic examination (BCEE), extended cardiac echocardiographic examination (ECEE), BCEE plus outflow tract view (BCEE + OTV), BCEE + OTV + 3VTV (BCEE plus outflow tract view plus three vessel and trachea view) for the prenatal diagnosis of CHD were 49.0%, 75.5%, 66.1%, and 83.7% respectively. The pooled sensitivity of the prenatal echocardiographic diagnosis of CHD during the first trimester, second trimester, the second to third trimester were 60.3%, 60.9%, and 77.4%, respectively. The pooled sensitivity of BCEE and ECEE for the prenatal diagnosis of CHD during the second to third trimester was significantly higher than that during the second trimester. The pooled sensitivity of the prenatal echocardiographic diagnosis of CHD for pregnancies with low risk, high risk, low and high risk, and unselected risk were 45.4%, 85.1%, 89.1%, and 66.2%, respectively. The sensitivity analysis was robust and risk level was significant source of heterogeneity. Deek test indicated no potential significant publication bias.Prenatal ultrasound is a powerful tool for the diagnosis of CHD; however, echocardiography has individual sensitivity for different gestation period, different levels of risk, and different echo-views.

Safety Indices during Fetal Echocardiography at the Time of First-Trimester Scan Are Machine Dependent

The aim of our study was to evaluate the thermal index (TI) and mechanical index (MI), during the assessment of the fetal heart at the time of first-trimester scan, with different ultrasound machines. This was part of an observational study conducted in patients undergoing routine first-trimester screening. Cases were examined with Voluson E8 or 730Pro scanners using 2–8 MHz transabdominal probes. TI and MI were retrieved from the saved displays while in gray mode, color flow mapping and pulsed-wave (PW) Doppler examinations of the fetal heart and also from the ductus venosus (DV) assessment. We evaluated 552 fetal cardiac examinations, 303 (55%) performed with Voluson E8 and 249 (45%) with Voluson 730Pro ultrasound machines. The gray-scale exam of the heart and the PW Doppler DV assessment had TI values significantly lower for the Voluson E8 group (median, 0.04 vs. 0.2 and 0.1 vs. 0.2, respectively). The MI values from gray-scale and color flow mapping of the heart were significantly lower (median, 0.6 vs, 1.2 and 0.7 vs. 1) and for PW Doppler exam of the tricuspid flow were significantly higher (median 0.4 vs. 0.2) in the Voluson E8 group. The TI values from Doppler examinations of the heart, either color flow or PW imaging and MI values from DV assessment were not significantly different between the two groups. A different (newer) generation of ultrasound equipment provides lower or at least the same safety indices for most of the first-trimester heart examinations.

Prenatal detection of congenital heart defects at the 11- to 13-week scan using a simple color Doppler protocol including the 4-chamber and 3-vessel and trachea views

OBJECTIVES

The first goal of this study was to analyze the diagnostic performance of the 4-chamber view, 3-vessel and trachea view, and their combination in color mapping during early cardiac evaluations for selecting cases suspicious of congenital heart defects. The second goal was to describe the most common abnormal flow patterns at the levels of the 4-chamber and 3-vessel and trachea views in the late first trimester.

METHODS

We conducted a prospective observational study in which a simple cardiac sonographic protocol was applied in fetuses at gestational ages of 11 weeks to 13 weeks 6 days.

RESULTS

A total of 1084 patients with known postnatal or autopsy findings were included in the study. The median maternal age was 32.3 years (range, 27-40 years). The median crown-rump length was 62.2 mm (range, 45-84 mm). Overall, there were 35 cases with a confirmed congenital heart defect (3.22%), including 16 accompanied by aneuploidy. We found that our simple first-trimester cardiac protocol was an effective screening method for congenital heart defects. The most effective approach of the 3 evaluated by us was the combined application of the 4-chamber and 3-vessel and trachea views in color mapping compared to the 4-chamber and 3-vessel and trachea views alone. We defined the most common ventricular inflow patterns and the V sign. The technique we used was simple and easy to reproduce.

CONCLUSIONS

We confirmed that evaluation by two basic cardiac views allows for selection of most cases with a univentricular heart, atrioventricular septal defects, coarctation of the aorta, pulmonary stenosis, pulmonary atresia, and conotruncal defects.

Advances in ultrasound imaging for congenital malformations during early gestation

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSION

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

Acoustic output measured by thermal and mechanical indices during fetal echocardiography at the time of the first trimester scan

We measured acoustic output, expressed as the thermal index (TI) and mechanical index (MI), during fetal echocardiography at the time of the first trimester scan. TI and MI were retrieved from the saved displays during gray-mode, high-definition color flow Doppler and pulsed-wave Doppler (tricuspid flow) ultrasound examinations of the fetal heart and from the ductus venosus assessment. A total of 399 fetal cardiac examinations were evaluated. There was a significant increase in TI values from B-mode studies (0.07 ± 0.04 [mean ± SD]) to color flow mapping (0.2 ± 0.0) and pulsed-wave Doppler studies (0.36 ± 0.05). The TI from ductus venosus assessment (0.1 ± 0.01) was significantly lower than those from Doppler examinations of the heart. MI values from B-mode scans (0.65 ± 0.12) and color flow mapping (0.71 ± 0.11) were comparable, although different, and both values were higher than those from pulsed-wave Doppler tricuspid evaluation (0.39 ± 0.03). There were no differences in MI values from power Doppler assessment between the tricuspid flow and ductus venosus. Safety indices were remarkably stable and were largely constant, especially for color Doppler (TI), tricuspid flow (MI) and ductus venosus assessment (TI, MI). We acquired satisfactory Doppler images and/or signals at acoustic levels that were lower than the actual recommendations and never reached a TI of 0.5.

Factors affecting the feasibility of routine first-trimester fetal echocardiography

OBJECTIVES

The purpose of our study was to assess the factors that may improve the feasibility of routine fetal echocardiography at the time of the first-trimester scan.

METHODS

In this prospective study, we included 616 healthy singleton fetuses. Examinations were performed transabdominally by a single sonographer at the beginning of his training in first-trimester screening. The fetal heart was examined by high-definition color Doppler imaging to obtain the 4-chamber view, right and left ventricular outflow tracts, and 3-vessel and trachea view. Logistic regression was used to investigate the effect on the ability to visualize different cardiac structures.

RESULTS

The frequency of successful heart examinations increased significantly with the number of scans performed (P < .05). The sonographer needed 180 examinations before he could successfully examine the heart in at least 80% of cases. Significant factors that increased the probability of adequate echocardiography were the length of the heart examination and the experience of the sonographer (P< .05) but not transducer-heart distance, maternal body mass index, fetal crown-rump length, placenta interposition, or restrictive fetal position. Visualization of the left ventricular outflow tract could be improved by increasing the experience of the sonographer and decreasing the transducer-heart distance. Also, visualization of the 3-vessel and trachea view depended on the length of the heart examination, the experience of the sonographer, an anterior position of the placenta, and a restrictive fetal position.

CONCLUSIONS

Competence in color flow mapping assessment of the fetal heart at gestational ages of 11 weeks to 13 weeks 6 days is achieved only after extensive supervised training.