Prospective evaluation of the antenatal incidence and postnatal significance of the fetal echogenic cardiac focus: a case-control study

Application of Copy Number Variation Detection to Fetal Diagnosis of Echogenic Intracardiac Focus During Pregnancy

Echogenic intracardiac focus (EIF) is one of the most common ultrasound soft markers (USMs) in prenatal screening. However, the association of EIF with chromosomal abnormalities is still controversial. From January 2018 to April 2020, a total of 571 fetuses with USMs in our center were enrolled, among which 150 (26.27%) presented EIFs. We analyzed the karyotype anomalies and copy number variations (CNVs) in fetuses who presented EIFs by comparing their ultrasound indications, maternal ages and gestational stages. There were no statistically significant differences in the incidence of chromosomal abnormalities between fetuses with EIFs and the fetuses with USMs (4.00 vs. 7.71%, p = 0.112). Additionally, the incidence of chromosomal abnormalities was not related to maternal age (4.10% in maternal age below 35 yeas vs. 3.57% in maternal age above 35, p = 1.000). Interestingly, after 28 weeks of gestation, fetuses with EIFs showed more chromosomal abnormalities (20.00%) than that in the group before 28 weeks of gestation (2.22%, p = 0.014), and this result was attributed to the detection of pathogenic CNVs. After birth, 25 of children conducted cardiac development re-examination. Among them, 9 (36%, 9/25) were diagnosed with congenital heart disease, primarily patent foramen oval and ventricular septal defects (7/9, 77.77%). We concluded that the appearance of EIFs in early or mid-trimester would not indicate an increased risk of fetal chromosomal abnormalities. However, the persistence of EIFs in late trimester was associated with a higher risk of pathology-related CNVs and its persistent appearance may indicate heart development defects after birth. Thus, our results suggest that CNV detection has its advantages in prenatal diagnosis, especially for those with EIFs that persist in the third trimester.

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.].

Isolated echogenic intracardiac foci and the role of cell-free fetal DNA: A cost-effectiveness analysis

OBJECTIVES

Cell-free fetal DNA (cfDNA) has been increasingly incorporated into prenatal aneuploidy screening paradigms given its relatively high sensitivity for Down syndrome (DS). This is often the case when fetal ultrasonographic soft markers are present, such as the relatively common echogenic intracardiac focus (EIF). We sought to evaluate the cost-effectiveness of a screening strategy that included cfDNA screening when an isolated EIF is identified in a low-risk population with prior aneuploidy screening.

METHODS

A decision-analytic model was constructed using TreeAge software with probabilities derived from the literature. Our model compared cfDNA screening following isolated EIF detection in women less than 35 years with prior reassuring first trimester screen compared to a strategy of no further aneuploidy screening. Strategies were compared to generate an incremental cost-effectiveness ratio with a threshold of $100 000/quality-adjusted life year (QALY) and applied to a theoretical cohort.

RESULTS

The cfDNA strategy resulted in 21 fewer DS births and 52 additional QALYs, however, increased costs by $51.3 million. This yielded an incremental cost-effectiveness ratio of $986 503; therefore, it was not a cost-effective strategy.

CONCLUSION

In a low-risk population with prior reassuring aneuploidy screening, it is not cost effective to offer cfDNA after identification of an isolated EIF.

Echogenic intracardiac focus on second trimester ultrasound: prevalence and significance in a Middle Eastern population

OBJECTIVE

The association between echogenic intracardiac focus (EIF) and trisomy 21 is well established, with a recognized ethnic variation. Our study aimed to determine the prevalence of EIF in a Middle Eastern population and to examine its association with trisomy 21 and other adverse pregnancy outcomes.

METHODS

Retrospective case-control study of second-trimester obstetric sonograms (16-28 weeks) performed at a tertiary care center over a 5-year period. Cases with EIF were retrieved, and a matched control group with no EIF was identified. The incidence of trisomy 21 and other adverse pregnancy outcomes was compared.

RESULTS

A total of 9270 obstetric sonograms were examined, with an EIF prevalence of 2.5% (95% CI: 2.2-2.8%). Of patients with available outcome data, EIF was not associated with trisomy 21 (0/163 versus 1/163; p value = 1.00). Additionally, EIF was not associated with trisomy 18, trisomy 13, small for gestational age, preterm birth, fetal demise, cesarean delivery, operative vaginal delivery, or admission to the neonatal intensive care unit.

CONCLUSION

In a contemporary Middle Eastern population, EIF is a rare occurrence. As an isolated finding, it is not associated with aneuploidy or other adverse pregnancy outcomes. EIF appears to be incidental with no impact on clinical practice.

Fetal imaging: executive summary of a joint Eunice Kennedy Shriver National Institute of Child Health and Human Development, Society for Maternal-Fetal Medicine, American Institute of Ultrasound in Medicine, American College of Obstetricians and Gynecologists, American College of Radiology, Society for Pediatric Radiology, and Society of Radiologists in Ultrasound Fetal Imaging workshop

Given that practice variation exists in the frequency and performance of ultrasound and magnetic resonance imaging (MRI) in pregnancy, the Eunice Kennedy Shriver National Institute of Child Health and Human Development hosted a workshop to address indications for ultrasound and MRI in pregnancy, to discuss when and how often these studies should be performed, to consider recommendations for optimizing yield and cost effectiveness, and to identify research opportunities. This article is the executive summary of the workshop.

Fetal imaging: Executive summary of a Joint Eunice Kennedy Shriver National Institute of Child Health and Human Development, Society for Maternal-Fetal Medicine, American Institute of Ultrasound in Medicine, American College of Obstetricians and Gynecologists, American College of Radiology, Society for Pediatric Radiology, and Society of Radiologists in Ultrasound Fetal Imaging Workshop

Given that practice variation exists in the frequency and performance of ultrasound and magnetic resonance imaging in pregnancy, the Eunice Kennedy Shriver National Institute of Child Health and Human Development hosted a workshop to address indications for ultrasound and magnetic resonance imaging in pregnancy, to discuss when and how often these studies should be performed, to consider recommendations for optimizing yield and cost-effectiveness and to identify research opportunities. This article is the executive summary of the workshop.

Fetal imaging: executive summary of a joint Eunice Kennedy Shriver National Institute of Child Health and Human Development, Society for Maternal-Fetal Medicine, American Institute of Ultrasound in Medicine, American College of Obstetricians and Gynecologists, American College of Radiology, Society for Pediatric Radiology, and Society of Radiologists in Ultrasound Fetal Imaging Workshop

Given that practice variation exists in the frequency and performance of ultrasound and magnetic resonance imaging (MRI) in pregnancy, the Eunice Kennedy Shriver National Institute of Child Health and Human Development hosted a workshop to address indications for ultrasound and MRI in pregnancy, to discuss when and how often these studies should be performed, to consider recommendations for optimizing yield and cost effectiveness, and to identify research opportunities. This article is the executive summary of the workshop.

The role of fetal echocardiography in the assessment of fetal aneuploidy

Advances in both imaging technology and understanding of fetal cardiac disease have contributed to a dramatic increase in the sensitivity and specificity of fetal echocardiography over the last few decades. Fetal echocardiography now plays an important role in the prenatal evaluation of fetuses with known or suspected aneuploidy. In this article, specific situations in which fetal echocardiography has a part in noninvasive aneuploidy screening algorithms are discussed.

Fetal echogenic cardiac foci: prospective postnatal electrocardiographic follow-up

OBJECTIVE

To determine postnatal electrocardiographic abnormalities in fetuses with echogenic cardiac foci (ECF) and no congenital heart disease (CHD).

STUDY DESIGN

A total of 41 fetuses with ECF and no CHD, were prospectively followed after birth with serial echocardiograms, electrocardiogram (ECG) and 24-h ECG (Holter). The primary outcome was presence of significant abnormalities in the ECG or Holter.

RESULT

ECF diagnosed at a mean (s.d.) of 25.6 (4.6) weeks gestation, were located in the ventricles and in the atria in 39 (95.1%), and 2 fetuses (4.9%), respectively. Postnatal follow-up was for 8.1 (4.6) months (range 1 to 24). None of the infants had any clinically significant abnormality in the ECG or Holter. ECF resolved in 10 infants (24.3%) by 24 months of age. There was no difference between infants with resolved or persistent ECF in various ECG or Holter measurements compared.

CONCLUSION

Fetuses with ECF and no CHD have no significant postnatal electrocardiographic abnormalities, irrespective of ECF persistence or resolution.

Intracardiac echogenic focus and fetal outcome - review of cases from a tertiary care centre in Karachi, Pakistan

OBJECTIVE

To study the outcome in fetuses with intracardiac echogenic focus (ICEF) at the time of second trimester scan.

METHODS

All women with the sonographic findings of ICEF from January 2009 to December 2010 were included in this retrospective study.

RESULTS

ICEF were found in 71 out of 8226 screened (0.86%) women. Mean maternal age in the population was 26.9 ± 3.9 years. Foci were the isolated marker in 69 (97%) cases. In two cases there were additional findings of choroid plexus cysts. A fetal echocardiograph was done only in 13 (18.3%) patients. Majority of these pregnancies (95.7%) had a normal outcome. Postnatal echocardiograph was performed in 11 neonates (15%) out of which one had a small VSD, and in another case Tetralogy of Fallot was found. In addition, Pulmonary artery hypertension was diagnosed in one case. There was one intrauterine fetal demise and two neonatal deaths in this cohort.

CONCLUSIONS

The prevalence of ICEF was 0.86% in our study population. About 95.77% of these cases had an uncomplicated perinatal outcome. It was an isolated finding in almost all cases. These findings will be helpful in counseling parents in our setting.

Intracardiac echogenic focus and fetal outcome

BACKGROUND

To study the outcome of the fetuses with intracardiac echogenic focus (ICEF).

METHODS

All patients who were found to have one or more ICEF on sonographic (US) examination at our center from January 2007 through January 2009 were included in this retrospective study. ICEF was defined as a discrete area of echogenicity noted in the left or right ventricle, which was as bright as bone. Patients were followed up to know pregnancy outcome.

RESULTS

Of 762 fetuses evaluated by US, 48 (6.3%) were found to have an ICEF. Thirty-one of these 48 fetuses had an isolated ICEF; 11 had associated major malformations, and the remaining 6 had no major US abnormalities but were found to have other soft markers. Invasive prenatal testing was done in 21 cases for risk factors other than ICEF and was found to be abnormal in two cases. Seven pregnancies were terminated due to associated major malformations.

CONCLUSION

The prevalence of ICEF was 6.3%. Of 31 fetuses with an isolated ICEF, outcomes of 28 fetuses are known and all neonates were reported to be normal at birth. Thus we infer that the presence of an isolated ICEF has no adverse effect on outcome of the neonate.

Discovery of soft markers on fetal ultrasound: maternal implications

OBJECTIVE

to explore women's experiences of referral to tertiary care on the basis of uncertain ultrasound findings.

DESIGN

a qualitative method using Rice and Ezzy's thematic analysis approach. Data were gathered through two in-depth interviews over a six to eight-month period.

PARTICIPANTS

a total of 20 interviews were conducted among pregnant women, purposively recruited at a tertiary facility. Inclusion criteria were based on detection of an isolated soft marker in an otherwise normal pregnancy.

DATA ANALYSIS

interview data were transcribed and data were subjected to thematic analysis.

FINDINGS

mothers journeyed through a temporal sequence of adjustment following referral to specialist services. Four distinct phases were identified: realisation; making sense of events; anxious waiting; and having no clear resolution.

CONCLUSION

trends of increasing prenatal surveillance together with advancing technology make this study timely and of global interest. Findings suggest that women identified as 'at risk' before being discharged uneventfully may be prone to attachment issues and a host of other difficulties. The complexities inherent in this experience should be of interest to a broad range of health professionals. An appreciation of this experience may assist midwives and other health professionals to provide more meaningful maternal support to women identified as 'at risk'.

Chromosomal and cardiac anomalies in fetuses with intracardiac echogenic foci

OBJECTIVE

To evaluate the prevalence of intracardiac echogenic foci (ICEF) and the association between ICEF and chromosomal and cardiac anomalies in Brazilian women.

METHODS

In a cross-sectional observational study, 373 of the 23,360 genetic sonograms performed at a private maternal-fetal medicine clinic over 5 years showed intracardiac echogenic foci (ICEF). These 373 sonograms were reviewed for chromosomal and cardiac anomalies and associations were analyzed using the chi(2) test or the Fisher exact test. P<0.05 was considered significant.

RESULTS

The prevalence of ICEF was 1.7%. Cardiac anomalies were detected in 10 sonograms (2.7%) and chromosomal anomalies in 14 (3.7%). There were cardiac defects in 6 (1.7%) of the 359 euploid fetuses with isolated ICEF. Of the 373 women who had fetuses with ICEF, 295 were younger than 35 years and 78 were 35 years or older. There were 6 fetuses (2.1%) with aneuploidy in the younger group and 8 (10.3%) in the older group.

CONCLUSION

The prevalence of ICEF was 1.7%, and there was an association between cardiac and chromosomal anomalies. Women carrying fetuses with ICEF should be offered fetal echocardiography and karyotyping.

Ethnicity and other factors that may affect the prevalence of echogenic intracardiac foci in the fetus

PURPOSE

To study ethnicity and other possible factors that may affect the incidence of echogenic intracardiac foci (EIF) when detected via sonographic examination.

MATERIALS AND METHODS

Patients were referred to our institution for sonographic evaluation from a wide range of practice formats, including both private obstetric practices as well as community outpatient clinics. The study protocol included presence or absence of EIF, maternal age, ethnicity, gestational age during the examination, optimal versus suboptimal scans, presence of other fetal malformations and sonographic markers, and presence of chromosomal anomalies. Fetal outcome was ascertained in 90% of the study group. For statistical analysis, the chi-square test and the Student t-test were used.

RESULTS

The study group included 1,543 patients who had a fetal anatomy survey between 16 and 24 weeks' gestation. The prevalence of EIF was similar in all 4 ethnic groups (Asian, Hispanic, black, and white). There were 76 cases of EIF-an overall prevalence of 4.9%. Seventy-one of these cases were isolated in the left ventricle, 2 were isolated in the right ventricle, and 3 showed multiple foci. The prevalence of EIF was similar between younger and older patients, early and late gestational age at the time of sonographic examination, and optimal and suboptimal sonograms. Fetuses with EIF had significantly more congenital anomalies and other sonographic markers compared with fetuses without EIF.

CONCLUSIONS

We did not find any significant difference in the prevalence of EIF among the 4 different ethnic groups. The association between congenital anomalies and other sonographic markers should be studied further.

[Role of "subtle" ultrasonographic signs during antenatal screening for trisomy 21 during the second trimester of pregnancy: meta-analysis and CPDPN protocol of the Grenoble University Hospital]

OBJECTIVE

A meta-analysis about subtle ultrasonographic signs in second trimester of pregnancy.

MATERIALS AND METHODS

196 articles dealing with the subject--from 1985 to July 2002--were studied. Data on the 11 reported signs were collected from 92 theoretically and/or statistically valid studies. Then, the studies were selected according to several criteria: isolated characteristic, defined thresholds, calculable sensitivity and specificity. After checking for homogeneity, a likelihood ratio was calculated for some of the signs.

RESULTS

This meta-analysis of the second trimester ultrasonographic signs of Down's syndrome enabled us to estimate the likelihood ratio (LHR) of six signs. At 22 weeks'gestation (WG) these signs are: pyelectasis equal to or greater than 5 mm; nuchal fold thickness equal to or greater than 6 mm; persistence of choroid plexus cysts; shortness of the femur and humerus below the tenth percentile; hyperechogenic bowe; and nasal bone length less than 2.5 mm.

CONCLUSION

These validated ultrasonographic signs are independent of nuchal translucency thickness at 12 WG and of maternal serum biochemistry. This allows to calculate a combinate risk for nuchal translucency, maternal serum biochemistry and second trimester ultrasonographic signs when they are validated.

An isolated intracardiac echogenic focus as a marker for aneuploidy

OBJECTIVE

This study was undertaken to evaluate the relationship of an isolated fetal intracardiac echogenic focus in a population of patients with a mixed risk for aneuploidy when presenting for prenatal diagnosis.

STUDY DESIGN

All women referred to our institution for screening ultrasound were prospectively evaluated for the presence of an intracardiac echogenic focus in the fetal heart. Each patient was evaluated for the presence of clinical risk factors including ultrasound findings, biochemical screening, and maternal age. The population of patients was then described and neonatal outcomes were obtained.

RESULTS

A total of 10,875 patients were referred and 176 cases of fetal intracardiac echogenic foci were evaluated. There was an overall prevalence of 1.6% in our population. The patients with other ultrasound findings and/or maternal age older than 35 years who underwent amniocentesis had 3 abnormal karyotypes identified and had identifiable risk factors. In the group less than 35 years, the relative risk was 2.55 of having an amniocentesis for an isolated echogenic focus (with no cases of fetal aneuploidy found) in comparison with our referred group of nonadvanced maternal age patients without any ultrasound markers or findings.

CONCLUSION

This isolated echogenic finding appears to be a benign variant and not an increased risk for fetal aneuploidy. The chromosomal abnormalities were seen in the group with risk factors including maternal age and/or other ultrasound findings. Evaluation of maternal age, biochemical markers, and ultrasound markers should be used together to help determine the risk of patients with an isolated echogenic focus.

Clinical implications of the prenatal sonographic finding of fetal myocardial echogenic foci

OBJECTIVE

The purpose of this study was to investigate the clinical implications of fetal echogenic foci limited to the myocardium of the ventricular wall (EMF) or intraventricular septum detected during prenatal sonography.

METHODS

A retrospective review of fetuses found to have EMF during prenatal sonography from April 1990 through December 2003 was undertaken. Videotapes and reports were reviewed to determine the indication for sonography, gestational age, location, sonographic characteristics of the masses, and additional fetal findings. Sources of outcome data included neonatal and pediatric records and echocardiographic reports.

RESULTS

Five fetuses were identified. Indications for sonographic evaluation included fetal growth (n = 4) and follow-up twin-twin transfusion syndrome (n = 1). Mean gestational age +/- SD at diagnosis was 23.7 +/- 8.0 weeks (range, 17.1-36.4 weeks). The EMF identified were within the right ventricular myocardium (n = 2), intraventricular septum (n = 1), left ventricular myocardium (n = 1), and myocardium of the cardiac apex (n = 1). All foci appeared sonographically "bright as bone." The foci ranged in size from 0.1 x 0.1 to 1.2 x 0.9 cm. Neonatal echocardiographic findings were reported as normal for each of the cases. Follow-up examinations available for up to 2.5 years of age showed normal cardiac function.

CONCLUSIONS

The prenatal identification of EMF is unlikely to lead to notable short-term pathologic conditions because the fetuses in this investigation had unremarkable neonatal and pediatric echocardiograms and normal cardiac function.

Controversial ultrasound findings

This article has reviewed a few of the more controversial findings in the field of obstetric ultrasound. For each one evidence-based strategies for the management of affected pregnancies have been suggested, derived from what the authors believe is the best information available. In some cases, this information is very limited, which can make counseling these patients extremely difficult. Some physicians find using specific likelihood ratios helpful in these complex discussions. An example of the relative likelihood ratios for several markers of trisomy 21 is illustrated in Table 10. Although the management of each of the findings discussed in this article is different, a few generalizations can be made. To begin with, the detection of any abnormal finding on ultrasound should prompt an immediate detailed ultrasound evaluation of the fetus by someone experienced in the diagnosis of fetal anomalies. If there is more than one abnormal finding on ultrasound, if the patient is over the age of 35, or if the multiple marker screen is abnormal, an amniocentesis to rule out aneuploidy should be recommended. Of the six ultrasound findings reviewed here, the authors believe that only echogenic bowel as an isolated finding confers a high enough risk of aneuploidy to recommend an amniocentesis in a low-risk patient. The other findings in isolation in a low-risk patient seem to confer only a modest increased risk of aneuploidy, if any, and this risk is certainly less than the risk of unintended loss from amniocentesis. Wherever possible, modifiers of this risk, such as maternal age, history, and first and second multiple marker screening, should be used to define more clearly the true risk of aneuploidy. As obstetric ultrasound moves forward, particularly into the uncharted waters of clinical use of three- and four-dimensional ultrasound, one can expect a whole new crop of ultrasound findings with uncertain clinical significance. Clinicians are well advised to await well-designed studies to determine the clinical significance of these findings before altering clinical care.

The association between isolated fetal echogenic cardiac foci on second-trimester ultrasound scan and trisomy 21 in low-risk unselected women

OBJECTIVES

To determine the prevalence of and the association between trisomy 21 and isolated fetal echogenic cardiac foci (FECF) identified in the second trimester in an unselected low-risk population.

METHODS

All cases with isolated FECF were collected by reviewing the antenatal ultrasound database for 3 consecutive years. In order to include all trisomy 21 cases for the same period, the regional cytogenetics database and pediatric databases were examined. A 2 x 2-table analysis was performed to establish the sensitivity, specificity and positive and negative predictive values of isolated FECF as a screening test for trisomy 21 in a low-risk unselected population.

RESULTS

In the 3-year period of the study the total number of deliveries was 11,105, of which 10,769 (97%) had a routine detailed anomaly scan between 16 and 24 weeks' gestation. There were 311 cases (2.9%) of isolated FECF. Among these there was only one case (0.3%) of trisomy 21. In the same period, the total number of trisomy 21 cases was 14. Accordingly, the sensitivity of isolated FECF for detecting trisomy 21 was 7.1% and the specificity was 97.1%. Positive and negative predictive values of FECF were 0.3% and 99.9%, respectively.

CONCLUSION

In an otherwise healthy pregnancy, the finding of isolated FECF on a routine second-trimester anomaly scan is normal and should not be considered as a risk factor for trisomy 21 in an unselected low-risk population.

An isolated echogenic heart focus is not an indication for amniocentesis in 12,672 unselected patients

OBJECTIVE

To evaluate the risk of Down syndrome in fetuses with a heart echogenic focus using the Bayes theorem and likelihood ratios in an unselected population.

METHODS

We prospectively evaluated 12,672 second-trimester sonographic features and extracted and examined a population with an echogenic focus for chromosomal anomalies.

RESULTS

There were 479 cases of echogenic focus; 90.4% were isolated, whereas 9.6% had associated findings. Eleven patients had fetuses with trisomy 21 (9 per 10,000). Eight of those did not have an echogenic focus, whereas 3 had a heart echogenic focus. Only 1 fetus with trisomy 21 had an isolated echogenic focus. The positive likelihood ratio for total cases of a heart echogenic focus and trisomy 21 was 7.25, whereas for an isolated echogenic focus, the positive likelihood ratio was 2.66.

CONCLUSIONS

The results of the statistical analysis showed that the risk of aneuploidy is increased in fetuses with an echogenic intracardiac focus; however, the finding should prompt a detailed structural survey and correlation with a priori risk. Amniocentesis need not be offered to patients who are otherwise at low risk and have an isolated echogenic intracardiac focus.

Childhood cardiac function after prenatal diagnosis of intracardiac echogenic foci

OBJECTIVE

To determine whether prenatally diagnosed intracardiac echogenic foci are associated with childhood cardiac dysfunction and persistence.

METHODS

Children in whom intracardiac echogenic foci were shown on prenatal sonography at 1 perinatal center underwent echocardiography at ages 2 to 7 years. A single pediatric cardiologist, blinded to the prenatal sonographic intracardiac echogenic focus locations, assessed cardiac function by measuring the left ventricular shortening fraction and myocardial performance index. The presence of tricuspid and mitral valve regurgitation was also sought. The secondary outcome was intracardiac echogenic focus persistence.

RESULTS

Twenty-five children, 14 (56%) male and 11 (44%) female, were examined at a mean age +/- SD of 3.0 +/- 1.0 years. Prenatally, 18 children (72%) had left ventricular intracardiac echogenic foci, and 7 (28%) had right ventricular intracardiac echogenic foci. The left ventricular shortening fraction was normal in all children. The overall mean left ventricular myocardial performance index (reference value, 0.36 +/- 0.06), was normal for both children with left ventricular intracardiac echogenic foci (0.36 +/- 0.06) and those with right ventricular intracardiac echogenic foci (0.36 +/- 0.04). Two children with left ventricular intracardiac echogenic foci had an isolated left ventricular myocardial performance index of greater than 2.5 SD above the mean. Trace tricuspid valve regurgitation and mitral valve regurgitation were noted in 13 (52%) and 2 (8%) of the children, respectively, similar to the general population. Left ventricular intracardiac echogenic foci persisted in 16 children (89%), whereas right ventricular intracardiac echogenic foci persisted in 2 (29%) (P = .007).

CONCLUSIONS

Prenatally diagnosed intracardiac echogenic foci are often persistent but not associated with childhood myocardial dysfunction.

Relationship of isolated fetal intracardiac echogenic focus to trisomy 21 at the mid-trimester sonogram in women younger than 35 years

OBJECTIVE

To determine whether an isolated echogenic intracardiac focus in the fetal heart in the mid-trimester (16-24 weeks) in women aged 18-34 years of age is associated with trisomy 21.

METHOD

This was a prospective population-based observational study. A search of all obstetric sonograms performed in our region from January 1997 to December 1999 was carried out. From 12,373 pregnancies we identified 267 cases of echogenic foci in the fetal heart. Trisomy 21 was detected in 38 deliveries (0.31%). An echogenic focus was seen in 193 of the 9167 women < 35 years of age who had an obstetric sonogram at 16-24 weeks' gestation, and an echogenic focus was seen in 67 of the 1968 women > 35 years. The study group comprised the 149 women aged 18-34 years who had an echogenic focus in the fetal heart as the only abnormality at an obstetric sonogram performed at 16-24 weeks' gestation.

RESULTS

There were no abnormal outcomes or cases of trisomy 21 among the 149 pregnancies with an echogenic focus as an isolated finding in women aged 18-34 years (0% (95% confidence interval, 0.00-2.43)). The prevalence of isolated echogenic focus was 1.6% for women < 35 and 1.8% for women >or= 35 years old. Of the 25 fetuses with trisomy 21 undergoing an obstetric sonogram at any gestational age, five (20%) had an echogenic focus. An isolated echogenic focus was present in one fetus with trisomy 21 seen at 26 weeks' gestation in a 17-year-old mother. Echogenic foci were single and in the left ventricle in 84.7% of cases.

CONCLUSION

An isolated echogenic focus in the fetal heart at mid-trimester ultrasound in women aged 18-34 years is not associated with increased risk for trisomy 21.

Use of genetic sonography for adjusting the risk for fetal Down syndrome

Systematic evaluation of ultrasound findings known to be associated with trisomy 21, at an appropriate gestational age, has been referred to as a genetic sonogram. A number of high-risk centers performing genetic sonography have reported detection of ultrasound abnormalities in the majority of fetuses with fetal Down syndrome. However, nonspecific markers are more commonly observed than structural abnormalities, which are detected in less than 20% of cases in a nonselected population. Also, the actual sensitivity of a genetic sonogram will depend on various factors including the markers sought, gestational age, reasons for referral, and of course the quality of the ultrasound. Appropriate use of a genetic sonogram can help to modify the risk of fetal Down syndrome by decreasing the risk when the ultrasound is normal, or increasing the risk when specific ultrasound markers are detected. The postultrasound risk can be estimated by applying specific likelihood ratios, reflecting the strength of individual markers, with the a priori risk based on maternal age alone, or combined with biochemical markers when known. We review this approach of age-adjusted ultrasound risk assessment for fetal Down syndrome and illustrate how the risk can be estimated. Individual sonographic markers are also discussed.

Sonographic grading of fetal intracardiac echogenic foci in a population at low risk of aneuploidy

PURPOSE

We screened pregnant women at low risk of a fetal chromosomal abnormality for the presence of fetal intracardiac echogenic foci (ICEF) and graded those foci by using sonographic gain reduction. Our objectives were to determine the interobserver reliability of the technique and the association of ICEF, by grade, with fetal aneuploidy.

METHODS

Pregnant women who were 18-35 years old, at low risk for fetal chromosomal abnormalities, and referred for targeted sonography at 16-24 weeks' menstrual age were eligible to participate. All patients whose fetuses had ICEF were offered fetal chromosomal analysis. The presence of ICEF was ascertained by an apical 4-chamber view of the fetal heart and graded independently by 2 examiners blinded to each other's assessment. Grading was based on the difference in echogenicity of the ICEF and the thoracic spine as the ultrasound gain was reduced; in grade 1, the ICEF image was lost before that of the thoracic spine; in grade 2, the ICEF and thoracic spine images disappeared at the same gain setting; and in grade 3, the thoracic spine image was lost before that of the ICEF.

RESULTS

During the 6-month study period, 383 eligible women were examined, and ICEF were seen in 35 fetuses (9.1%): 25 (71.4%) in the left ventricle, 1 (2.9%) in the right ventricle, and 9 (25.7%) in both ventricles. ICEF grading was successfully performed in all 33 of the women with fetal ICEF who elected to participate. Twenty-one (63.6%) had grade 1, 9 (27.3%) had grade 2, and 3 (9.1%) had grade 3 ICEF. Interobserver agreement was noted in 27 (90.0%) of 30 available paired second-trimester observations (kappa = 0.8), indicating excellent agreement. Two fetuses (6.1%) with grade 1 ICEF but no other risk factors for aneuploidy had chromosomal abnormalities, as compared with 1 fetus (0.3%) in the control group, which had no ICEF (p = 0.02).

CONCLUSIONS

Sonographic grading of ICEF is feasible and reliable. The presence of fetal ICEF in a population otherwise at low risk for aneuploidy seems to warrant the performance of fetal chromosomal analysis.

Isolated echogenic foci in the fetal heart: do they increase the risk of trisomy 21 in a population previously screened by nuchal translucency?

OBJECTIVES

To confirm the hypothesis that isolated cardiac echogenic foci at the second-trimester anomaly scan do not influence our current calculation of risk of trisomy 21 in individual pregnancies, which is based on maternal age and nuchal translucency thickness at 11-14 weeks.

DESIGN

Observational study in a fetal medicine unit.

METHODS

In a general pregnant population undergoing first-trimester nuchal translucency screening, data from 239 singleton pregnancies with isolated cardiac echogenic foci at the second-trimester anomaly scan were compared with those of a control group of 7449 pregnancies with normal anomaly scans. Prevalence of trisomy 21 was determined in both groups. Following the anomaly scan, the individual risks of trisomy 21 were calculated by adjusting the previous risk based on maternal age and first-trimester nuchal translucency. We assumed that echogenic foci did not alter each individual risk calculation. The expected number of cases of Down syndrome in both groups was then calculated from the sum of probabilities of each individual affected fetus. The observed number of cases was compared with the expected number in both study and control populations.

RESULTS

There was no statistically significant difference between the prevalence of trisomy 21 in the study group (no cases) and in the control population (three cases). From individual risk calculations, observing no cases of trisomy 21 in the study group was the most likely event if echogenic foci did not increase the risk of this chromosomal abnormality (P = 0.62).

CONCLUSION

The finding of isolated echogenic foci at the time of the 20 week-scan does not significantly change the risks of trisomy 21 if background risk and previous nuchal translucency measurements are taken into account in the individual risk calculation. We suggest that no further adjustments to risk should be used.

Cardiac function in fetuses with intracardiac echogenic foci

OBJECTIVE

To evaluate cardiac dimensions and function in euploid fetuses with intracardiac echogenic foci.

STUDY DESIGN

Forty-eight fetuses with a single cardiac echogenic focus situated in the left ventricle had echocardiography performed at 22-24 weeks of gestation. Fifty normal fetuses at 22-24 weeks' gestation served as controls. Two-dimensional and M-mode directed fetal echocardiography were used to exclude cardiac anomalies and measure right and left ventricular free walls and interventricular septal thickness and ventricular systolic and diastolic dimensions. Cardiac size was expressed as a ratio of ventricular wall thickness/biparietal diameter, and cardiac function was expressed as ventricular shortening fraction. Doppler fetal echocardiography measurements included pulmonary and aortic maximum systolic velocities and time to peak velocities as indices of ventricular systolic function, and the ratio between early ventricular filling (E-wave) and active atrial filling (A-wave) peak velocities at the level of the atrioventricular valves as an index of ventricular diastolic function.

RESULTS

Early ventricular filling/active atrial filling peak velocity ratios were significantly lower in fetuses with intracardiac echogenic foci than in control fetuses. In the mitral valve the ratio was 0.37 +/- 0.14 (0.039) (mean +/- SD (95% confidence interval for difference between the means)) vs. 0.59 +/- 0.19 (0.052) and in the tricuspid valve it was 0.42 +/- 0.16 (0.045) vs. 0.62 +/- 0.21 (0.058). No significant differences were found in cardiac dimensions, ventricular shortening fraction and Doppler systolic indices.

CONCLUSION

Euploid fetuses with intracardiac echogenic foci show low E/A ratio values in midtrimester echocardiography. This finding might indicate cardiac diastolic dysfunction.

The value of minor ultrasound markers for fetal aneuploidy

As a result of improvements in ultrasound image quality and scanning technique, an increasing number of subtle morphological changes in fetal anatomy have been identified in the second trimester. Most of these ultrasound features were originally described as normal variants of development with no clinical significance. However, subsequent studies in high-risk populations showed that some of these variants were more prevalent in fetuses with chromosomal defects and therefore proposed as prenatal markers for the detection of aneuploidy. The implications for pregnancy management when one of these so-called minor ultrasound markers is detected have been a matter of continuous controversy in the field of prenatal diagnosis and yet the definitive answer on their clinical significance in the low-risk population is still debated.

Sonographic markers of fetal aneuploidy

A variety of ultrasound findings can be identified in fetuses with fetal aneuploidy. Typical findings vary with both the chromosome abnormality and gestational age at time of the ultrasound examination. Increased NT is the primary marker during the first trimester, whereas a variety of markers may be seen during the second trimester. The presence of ultrasound markers increases the risk for fetal aneuploidy, whereas a normal ultrasound reduces the risk. Optimal risk assessment includes consideration of other risk factors including maternal age, family history, and biochemical markers. It is expected that combined risks, incorporating ultrasound findings and biochemistry, will be available in the near future. How first-trimester screening is integrated with second-trimester screening remains to be determined.

Technical factors influencing sonographic visualization of fetal echogenic intracardiac foci

PURPOSE

A fetal echogenic intracardiac focus (EIF) is most commonly a normal variant in a normal fetus, but owing to reports of an increased risk of aneuploidy with EIFs, the finding causes concern when noted on routine obstetric sonograms. This study was undertaken to determine which factors influence the sonographic visualization of fetal EIFs.

METHODS

In part 1 of the study, records from 1,920 fetal sonographic examinations were reviewed for fetal age, indication for sonography, and abnormal findings. For all cases with EIFs recorded and 645 randomly selected cases with no record of EIFs, sonograms were reviewed for heart position at the time of the 4-chamber view, technologist performing the examination, fetal position, heart visibility, transducer frequency, machine type, amount of amniotic fluid, and presence/absence of an EIF. In part 2 of the study, machine settings were evaluated with respect to visualization of EIFs.

RESULTS

In part 1 of the study, only the technologist performing the examination and the fetal position were associated with visualization of EIFs. In part 2 of the study, we found that the standard obstetric mode settings are better for visualization of EIFs than are the fetal echocardiographic mode settings.

CONCLUSIONS

We conclude that technical factors influence visualization of EIFs.

Second trimester markers of aneuploidy

The risks of aneuploidy associated with identification of a sonographic marker in the low risk population is controversial. Prior risk estimates have been derived usually from high risk populations. Screening programmes in the first trimester, second trimester and combined first and second trimester will undoubtedly alter the second trimester scan as a screening tool for aneuploidy. This chapter reviews the current sonographic markers and the difficulties in their application to the general population.

A preliminary study of sonographic grading of fetal intracardiac echogenic foci: feasibility, reliability and association with aneuploidy

OBJECTIVES

To prospectively and quantitatively grade intracardiac echogenic focus/foci (ICEF) using sonographic gain reduction and to determine the association of ICEF by grade with fetal aneuploidy.

METHODS

Women referred for raised maternal age (> or = 35 years), or > 18 years of age and with a Down syndrome risk > or = 1/270, increased trisomy 18 risk by second trimester serum screen or a prior aneuploid offspring were included in this institutionally approved protocol. Only pregnancies of gestational age between 14 and 24 weeks were included. All women had a targeted ultrasound and were offered fetal chromosome analysis. The classification of ICEF was made from a four-chamber view of the fetal heart. The echo amplitude of the ICEF was compared to that of the thoracic spine and categorized according to the comparative gain setting at which the image of the relevant structure disappeared: Grade O = no ICEF present, Grade 1 = ICEF image lost before thoracic spine when gain was reduced, Grade 2 = ICEF image lost at same gain setting as thoracic spine, Grade 3 = thoracic spine image lost before ICEF. The primary outcome was a prenatally or post-natally detected chromosomal abnormality.

RESULTS

A total of 885 eligible women were examined during the 21-month study period. ICEF were seen in 29 (3.3%) fetuses: 24(83%) in the left ventricle and five (17%) in the right ventricle. A chromosome abnormality was identified in 13/671 (1.9%) fetuses without ICEF (Grade 0) and 0/21 (0%) fetuses with Grade 1 ICEF. In contrast, two of five (40%) fetuses with Grade 2 ICEF were aneuploid (P = 0.005). No Grade 3 ICEF were observed. Additional sonographic abnormalities were seen in both aneuploid fetuses with Grade 2 ICEF. Interobserver agreement on ICEF grading was noted in 50/50 (100%) examinations (kappa = 1.0).

CONCLUSIONS

Sonographic grading of ICEF is feasible and highly reliable. Grade 2 ICEF, especially when accompanied by additional sonographic markers of a chromosomal abnormality, are associated with aneuploidy significantly more frequently than Grade 1 ICEF.

Echogenic intracardiac focus in 2nd-trimester fetuses with trisomy 21: usefulness as a US marker

PURPOSE

To determine whether there is a relationship between the presence of an echogenic intracardiac focus in 2nd-trimester fetuses and trisomy 21 (Down syndrome).

MATERIALS AND METHODS

A complete genetic ultrasonographic (US) scan was obtained in 3,303 consecutive fetuses with an estimated gestational age of 14.0-24.0 weeks (mean +/- SD, 17.1 weeks +/- 1.75). US was performed in a prospective fashion without any knowledge of karyotype and included assessment of any potential echogenic intracardiac focus (ie, calcified papillary muscle). Karyotypes were obtained in all fetuses. Maternal ages ranged from 13.0 to 47.4 years (mean, 35.1 years +/- 5.1). The prevalence of Down syndrome in this population was 1.6% (53 of 3,303 fetuses).

RESULTS

An echogenic intracardiac focus was seen in 147 of the 3,192 karyotypically normal fetuses (4.6%) and 16 of the 53 fetuses with trisomy 21 (30%). The positive predictive value (PPV) of an echogenic intracardiac focus in this high-risk population was 9.8%; sensitivity, 30%; specificity, 95%; likelihood ratio, 6.6; and relative risk (RR), 8.2 (P <.001). For a sonographically isolated echogenic intracardiac focus, the PPV was 3.7%; sensitivity, 19%; specificity, 95%; likelihood ratio, 4.2; and RR, 4.8 (P =.002).

CONCLUSION

A sonographically isolated echogenic intracardiac focus (no other anomalies or markers noted on a complete genetic sonogram) was associated in our high-risk population with a 4.8-fold (95% CI: 1.8, 12.5) increase in RR for trisomy 21 (P =.002).

Fetal intracardiac echogenic foci: current understanding and clinical significance

The detection of fetal intracardiac echogenic foci (ICEF) by ultrasound was first reported in 1987. Despite many investigations, the relationship of ICEF with congenital heart malformations and chromosomal abnormalities remains unclear. This review describes the current understanding of ICEF based on a literature search from 1980 to the present. ICEF are observed in 0.5 to 20 percent of fetuses, with an overall frequency of 5.6 percent. These small, discrete structures near the papillary muscles and chordae tendinae move in synchrony with the intraventricular valves. They likely represent microcalcification of the papillary muscles. ICEF are most commonly seen in the left ventricle and occasionally in the right ventricle or bilaterally. Intra-atrial or diffuse ICEF are rare. In the chromosomally normal fetus, ICEF are not associated with congenital heart defects. The presence of ICEF in fetuses at high risk for chromosomal abnormalities suggests an increased possibility of aneuploidy, especially if other sonographic markers are noted. A similar association is observed with trisomy 21 in particular. The significance of ICEF in fetuses at low risk for aneuploidy is less clear and represents an area for future research.

Pathologic correlation of sonographic echogenic foci in the fetal heart

The goal of the current paper is to present, on the basis of six investigated fetal hearts, the pathological substrate of prenatally, sonographically diagnosed echogenic intramyocardial foci. The right ventricle, left ventricle, interventricular septum and papillary muscles of both ventricles of six hearts of the fetuses of high-risk pregnant women showing sonographically diagnosed intramyocardial echogenic foci were investigated. At termination of pregnancy all the women were between the 20th and the 24th week of gestation. Of the six cases, four were induced abortions and two were spontaneous abortions. For the control group we investigated the hearts of two fetuses without heart defects at the 22nd and 23rd week of gestation which had proven extracardial anomalies and a normal karyotype. Both cases were induced abortions which prenatally showed no echogenic cardiac foci. In all eight cases a prenatal karyotyping was performed. In the six cases with echogenic foci the location and number of the foci were determined both prenatally and by means of histologic sections; the size of the foci was measured as well. Histological staining was with routine haematoxylin-eosin; Masson-Goldner was used for connective tissue; Kossa for calcification; and Berlin blue for haemosiderin. Histologically, in all six cases, intramyocardial calcifications surrounded by fibrotic tissue were in: papillary muscle of the left ventricle in six cases; papillary muscle of the right ventricle in one case; and the subendocardial myocardium of the right ventricle in one case. Four cases had one, one case had two and one case had three calcified foci. Three cases had cardiac and two cases had extracardiac anomalies. Four cases had chromosome anomalies: two were trisomy 21, one trisomy 13 and one triploidy. The remaining two cases had a normal karyotype. No case showed pathological changes of the chordae tendinae, myocardial cell necrosis or inflammation. There were no patho-morphological differences between the intramyocardial calcifications of the papillary muscles in cases with chromosome anomalies and with normal karyotype. As the patho-morphological correlate of the sonographically diagnosed echogenic foci, histological investigation on all six fetal hearts showed coarse intramyocardial calcifications surrounded by myocardial fibrosis. Conventional histological methods gave no indication of the cause of the intramyocardial calcifications.

Ultrasound screening for fetal chromosome anomalies

Ultrasound evidence for aneuploidy may be found in almost every organ of the fetus and can be used to modify the risk of aneuploidy. The diagnosis of these minor anomalies on second-trimester ultrasonography will increase the risk of an abnormal karyotype whereas the absence of these findings may reduce this danger. The most specific and most ominous isolated markers for fetal aneuploidy are nuchal findings (edema or cysts), indicating the need to obtain a fetal karyotype in all cases irrespective of maternal age or results of biochemical serum screening. Hyperechoic fetal bowel is apparently also a strong indicator of fetal aneuploidy. Other isolated sonographic markers may increase the risk of an abnormal karyotype three- to ninefold. Most sonographic markers for aneuploidy specify an increased risk for Down syndrome, but choroid plexus cysts are apparently more specific for trisomy 18. Along with other screening methods, ultrasound screening for fetal aneuploidy should be used routinely to identify additional pregnancies at need for evaluation of fetal karyotype.

Isolated fetal echogenic intracardiac foci or golf balls: is karyotyping for Down's syndrome indicated?

OBJECTIVE

To determine the prevalence of isolated echogenic intracardiac foci and the subsequent risk for Down's syndrome at 18-23 weeks in an unselected obstetric population.

DESIGN

Prospective study.

SETTING

A district general hospital serving a routine obstetric population.

PARTICIPANTS

16,917 pregnant women who underwent a routine ultrasound screening at 18-23 weeks of gestation between November 1994 and August 1998.

METHODS

All women were offered screening for Down's syndrome by nuchal translucency or maternal serum biochemistry. The prevalence of isolated echogenic intracardiac foci was determined and the relative risk for Down's syndrome was calculated for different ultrasound findings.

RESULTS

The combined sensitivity of age, nuchal translucency and maternal serum biochemistry for Down's syndrome was 84% (27/32). The relative risk for Down's syndrome was 0.17 (95% CI 0.07-0.41) for the women with normal scan findings at 18-23 weeks. The prevalence of isolated echogenic intracardiac foci at 18-23 weeks was 0.9% (144/16,917). None of these pregnancies were affected by Down's syndrome.

CONCLUSION

The significance of the association between isolated echogenic intracardiac foci and Down's syndrome is a matter of ongoing debate. The data of this study suggest that in an unselected obstetric population with prior, effective, routine Down's syndrome screening, the association between isolated echogenic intracardiac foci and Down's syndrome is no longer significant.

Borderline findings in fetal cardiac sonography

Borderline or equivocal sonographic findings in the fetal heart are occasionally encountered. Echogenic foci in the ventricles, small pericardial effusions, and mild discrepancy in ventricular size are three such problematic findings. The significance of each of these findings, as currently understood, will be discussed in this article.