Cardiac function in fetuses with intracardiac echogenic foci

Childhood Outcomes in Children with and without Cardiac Echogenic Foci: An Electronic Birth Cohort Study in Wales, UK

There is uncertainty about outcomes associated with cardiac echogenic foci (CEF) seen at the midtrimester ultrasound scan because of limited population-based follow-up data. This can lead to unnecessary invasive testing and significant parental anxiety. We analysed data from a cohort study, The Welsh Study of Mothers and Babies, to examine whether children with CEF had more adverse outcomes during childhood compared with children without CEF. Children born between 1 January 2009 and 31 December 2011 were followed until 31 January 2018, migration out of Wales, or death. The primary outcome was cardiac hospital admissions, defined a priori by an expert steering group. Secondary outcomes included congenital cardiac anomalies, and hospital admissions for other causes. There was no evidence of an association between isolated CEF and cardiac hospital admissions (hazard ratio 0.87, 95% confidence interval [CI] 0.33-2.25, p value 0.768), or with congenital cardiac anomalies. There was a small increased risk of a respiratory admission with isolated CEF (hazard ratio 1.27, 95% CI 1.04-1.54, p value 0.020). Further research is needed on features of CEF, such as location or number, to fully understand the clinical significance of these findings.

Effectiveness of Chromosomal Microarray Analysis for Prenatal Diagnosis of Fetal Echogenic Intracardiac Focus: A Single-Center Experience

BACKGROUND

Echogenic intracardiac focus (EIF) is a common ultrasound finding during pregnancy. However, the correlation between fetal EIF and cardiac abnormality remains in dispute until now. The study aimed to examine the association of fetal EIF with chromosomal abnormality by means of chromosomal microarray analysis (CMA).

MATERIALS AND METHODS

A total of 192 pregnant women with fetal EIF undergoing amniocentesis or umbilical cord blood puncture were recruited and assigned into groups A (8 cases with isolated EIF alone), B (75 cases with EIF and other cardiac malformations) and C (109 cases with EIF and extracardiac malformations). All fetuses underwent karyotyping analysis and CMA simultaneously. The detection of chromosomal abnormality and copy number variations (CNVs) were compared.

RESULTS

Chromosomal karyotyping identified 5 fetuses with chromosomal abnormality, including 3 cases with trisomy 21, one fetus with Turner's syndrome, and one fetus with chromosome 8 mosaicism, while CMA detected 6 additional fetuses with CNVs, including 2 fetuses with pathogenic CNVs and 4 fetuses with variants of uncertain significance (VOUS). There was no significant difference among groups A (0), B (5.33%) and C (6.42%) in terms of the prevalence of chromosomal abnormality (P> 0.05). Among the 4 fetuses with VOUS, pregnancy continued in 2 fetuses, and pregnancy was terminated in other 2 fetuses.

CONCLUSION

An isolated EIF may not correlate with chromosomal abnormality. However, CMA is recommended in fetuses with CMA complicated by other abnormal cardiac ultrasound findings, which facilitates the prediction of fetal outcomes during the genetic counseling and precision assessment of prognosis.

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.

Utility of ductus venosus blood flow in the study of cardiac function in fetuses with intracardiac echogenic focus

PURPOSE

The purpose of this study was to investigate fetal ductus venosus (DV) wave velocities, DV velocity ratios, and DV diastolic time intervals to derive additional information on fetal cardiac function in the presence of an intracardiac echogenic focus (IEF).

METHODS

Seventy fetuses at 19-28 weeks of gestation with an IEF and 63 control fetuses were screened using two-dimensional and power Doppler echocardiography. DV wave velocities, DV velocity ratios, and diastolic time intervals were measured. The aortic peak velocity, pulmonary artery peak velocity, left ventricular shortening fraction, and right ventricular shortening fraction, atrioventricular early-diastolic filling velocity (E), atrial contraction velocity (A), and E/A ratio were also measured.

RESULTS

The study and control groups were similar in terms of maternal age, body mass index, and gestational age in weeks at the time of examination (p > 0.05). Significant between-group differences were found in DV v-descent (p = 0.03) and a-wave velocities (p = 0.04).

CONCLUSIONS

Although the presence of an IEF in the fetal heart does not influence conventional measurements (DV velocity ratios and DV diastolic time intervals), it is associated with changes in DV v-descent and a-wave velocities. These changes may be indirectly related to reduced end-systolic relaxation and augmented atrial contraction in the fetal heart. We therefore suggest examination of DV flow velocities in fetuses with IEF.

Modified myocardial performance index is not affected in fetuses with an isolated echogenic focus in the left ventricle

OBJECTIVES

We prospectively investigated the efficacy of modified myocardial performance index (mod-MPI) in the assessment of cardiac functions in fetuses with and without an isolated hyperechogenic focus (IHF) in the left ventricle and compared with conventional fetal echocardiography.

METHODS

The study group consisted of 50 fetuses with only an IHF in the left ventricle, without any other cardiac or extracardiac anomalies; 50 fetuses without IHF served as controls. All fetal echocardiographic studies were performed between 20th and 24th weeks of gestation. Left ventricular functions were evaluated with both conventional echocardiographic methods (peak velocity of the aortic valve, mitral E/A ratio, fractional shortening) and mod-MPI.

RESULTS

There was no statistically significant difference between the groups in terms of maternal age, BMI or gestational age at the time of examination (p > 0.05 for all). No statistically significant differences were found between the findings of conventional echocardiographic measurements and left ventricular mod-MPI between the study and control groups (p > 0.05 for all).

CONCLUSION

Fetal left ventricular mod-MPI is not affected by the presence of an IHF in the fetal left ventricle between 20th and 24th gestational weeks and thus it does not need to be assessed in this situation.

Evaluation of tissue Doppler-derived myocardial performance index in fetuses with intracardiac echogenic focus

OBJECTIVE

To compare cardiac function between fetuses with and without intracardiac echogenic foci (IEFs) by conventional echocardiography and tissue Doppler (TD) imaging.

METHODS

Fetuses having IEF and no additional cardiac or extracardiac anomaly between 20 and 28 weeks (median 22 weeks) of gestation (n = 61) were compared with healthy fetuses between 18 and 29 weeks (median 23 weeks) of gestation (n = 55). Pulmonary artery and aortic peak velocities, atrioventricular (AV) early diastole (E) and atrial contraction (A) velocities and E/A ratios were measured. TD-derived myocardial performance index (MPI) was also measured.

RESULTS

Tricuspid valve E/A ratios, which were 0.634 ± 0.07 versus 0.639 ± 0.06 (p = 0.697), mitral valve E/A ratios, which were 0.604 ± 0.08 versus 0.612 ± 0.07 (p = 0.600), aorta peak velocities, which were 0.709 ± 0.11 versus 0.697 ± 0.11 (p = 0.592) and pulmonary artery peak velocities, which were 0.699 ± 0.12 versus 0.694 ± 0.11 (p = 0.800) in the study and the control groups, respectively. TD-derived measurements in the study and control groups included tricuspid valve MPI, which were 0.452 ± 0.08 versus 0.473 ± 0.09 (p = 0.221) and mitral valve MPI values, which were 0.444 ± 0.1 versus 0.445 ± 0.09 (p = 0.965), respectively, and this difference was not statistically significant.

CONCLUSION

An isolated IEF is not associated with abnormal cardiac function. We suggest that the presence of an isolated IEF should not be an indication for fetal cardiac function examination either with conventional Doppler or TD imaging techniques, unless there is a coexisting cardiac or extracardiac anomaly.

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 foci have no hemodynamic significance in the fetus

Intracardiac echogenic foci (ECFs), probably representing microcalcifications of the papillary muscles, are a common finding in fetal ultrasonic screening examinations. Their significance is unclear, and their value as markers for chromosomal anomalies is debatable. It also is unknown whether ECFs predict abnormal cardiac performance. This prospective study analyzed and compared the systolic and diastolic properties of the heart in 28 fetuses with ECFs and 70 fetuses without ECFs using both conventional and novel myocardial deformation methods. The findings suggest that left-sided ECFs do not predict depressed left- or right-side systolic or diastolic properties in the fetus. A longitudinal study that would follow ECF fetuses into their childhood is warranted to confirm the findings of this study.

Isolated fetal intracardiac hyperechogenic focus associated with neonatal outcome and triple test results

OBJECTIVE

To investigate the relationship between isolated intracardiac hyperechogenic focus (IHF) in the mid trimester of pregnancy with neonatal outcomes and triple test results.

MATERIALS AND METHODS

The study included low-risk pregnant women who came for routine follow-up to our antenatal clinic between years 2000 and 2005. A detailed structural survey by ultrasound (USG) of the fetal heart was performed on each fetus in the mid-trimester of pregnancy. All patients had mid-trimester triple tests performed between the 16th and 18th weeks' of pregnancy. We recruited a total of 40 pregnancies that had fetal IHF in the level II USG examination and a control group of 100 healthy pregnant women those which were followed-up during the same period. Twenty-nine fetuses (72.5%) had left, 8 (20%) had right whereas 3 (7.5%) had bilateral ventricular IHF. We compared the perinatal and neonatal outcomes and triple test results of the fetuses that had right and left IHF, and the controls.

RESULTS

Cytogenetic amniocentesis was performed to 6 (15%) women in the study and 5 (5%) in the control group and all were normal. During follow-up IHF spontaneously disappeared in 30 fetuses [right (n: 5), left (n: 23) or bilateral (n: 2)]. We did not observe any cardiac problem in the postnatal period in all newborns. Only one infant (2.5%) in the study group was admitted to neonatal intensive care unit because of prematurity. Median delivery weeks (P = 0.023), head circumference (P = 0.013), 5-min Apgar score (P = 0.021] and apnea (P = 0.042) were significantly higher in fetuses with right IHF. Compared to the controls, median delivery weeks (P = 0.038) was significantly higher in fetuses with right IHF, but head circumference (P = 0.004), 1-min (P = 0.003) and 5-min (P < 0.001) Apgar scores were lower in fetuses with left IHF. However no difference was observed in second-trimester serum human chorionic gonadotropin (HCG), alpha-fetoprotein (AFP) and estriol (E(3)) levels, in the three groups. There was no correlation between serum HCG, AFP and E(3) levels and the presence of IHF.

CONCLUSIONS

Isolated IHF in the fetal heart in the mid-trimester of pregnancy seems not associated with adverse neonatal outcome and does not correlate with triple test results.

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.

Echogenic intracardiac focus: potential for misdiagnosis

OBJECTIVE

To assess the potential rate of specular reflectors within the fetal heart producing reflections of sufficient amplitude to be mistaken for echogenic intracardiac foci.

METHODS

Between July 1999 and December 2000, 200 patients were randomly selected from the University of California, San Francisco, perinatal database who met the following criteria: (1) had singleton pregnancy, (2) delivered at University of California, San Francisco, and (3) had obstetric sonography at University of California, San Francisco, between 18 and 22 weeks' gestation. Bright focal reflections within the heart were judged to be either "true" or "false" echogenic intracardiac foci.

RESULTS

In this population of patients who underwent routine obstetric sonography at a tertiary care hospital, the rate of true echogenic intracardiac focus cases was 11 per 200 (5.5%). The rate of false echogenic intracardiac focus cases was 34 per 200 (17%). The most common locations for identification of a spurious echogenic intracardiac focus were the endocardial cushion, the moderator band, and the tricuspid valve annulus.

CONCLUSIONS

A specular reflection from the moderator band was judged the false echogenic intracardiac focus most likely to fool examiners. The rate of specular reflection from the moderator band was 11 per 200 (5.5%). Because it is possible to generate a specular reflection from an interface in the fetal heart in virtually any patient, it is important to exercise caution before diagnosing an 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.

Prenatal evaluation for fetal surgery

The selection of fetuses that may benefit with in utero surgery is being developed. Noninvasive and invasive prenatal diagnosis techniques are utilized to try and gain as much knowledge about the fetus so that the appropriate counseling of parents can be undertaken. The most common invasive techniques are amniocentesis and chorionic villus sampling for fetal karyotyping and genetic diagnosis. Noninvasive techniques include ultrasound (2D and 3D), fetal echocardiography and magnetic resonance imaging. Additional techniques such as specific Doppler evaluation of vascular components, new techniques to look at fetal electrocardiograms and the use of computer tomography are also considered. The most common conditions for which in utero fetal surgery is also being considered are twin to twin transfusion syndrome, myelomeningocele, sacrococcygeal teratoma, cystic adenomatoid malformation of the lung with fetal hydrops and other monochorionic twin abnormalities (severe discordant birth defects or twin reversal arterial perfusion sequences). Ongoing evaluation of the sensitivity, specificity, positive and negative predicted values of these evaluation tools is required so that appropriate selection of fetuses for the surgery can be made.