Isolated sonographic markers for detection of fetal Down syndrome in the second trimester of pregnancy.

OBJECTIVE: To determine whether sonographic "markers" are associated with fetal Down syndrome during the second trimester and to estimate the degree of risk of individual markers using likelihood ratios. METHODS: Second-trimester (14-20 weeks) sonographic findings in 186 fetuses with trisomy 21 were compared with a control group of 8728 consecutive control fetuses. Six markers were evaluated: nuchal thickening, hyperechoic bowel, shortened femur, shortened humerus, echogenic intracardiac focus, and renal pyelectasis. RESULTS: Major or structural abnormalities were observed in 31 fetuses with trisomy 21 (16.7%) and 53 control fetuses (0.6%) (P< .001). Some type of sonographic finding (major abnormality, minor marker, or both) was observed in 68.8% of fetuses with trisomy 21 compared with 13.6% of control fetuses (P < .001). An isolated minor or "soft" marker was the only sonographic finding in 42 (22.6%) of 186 fetuses with trisomy 21 compared with 987 (11.3%) of 8728 control fetuses (P < .001). Nuchal thickening (P < .001; likelihood ratio, 11) and hyperechoic bowel (P < .001; likelihood ratio, 6.7) showed the strongest association with trisomy 21 as isolated markers, followed by shortened humerus (likelihood ratio, 5.1), echogenic intracardiac focus (likelihood ratio, 1.8), shortened femur (likelihood ratio, 1.5), and pyelectasis (likelihood ratio, 1.5). Echogenic intracardiac focus was the single most common isolated marker in both affected fetuses (7.1%) and control fetuses (3.9%) but carried a low risk (P= .046; likelihood ratio, 1.8). CONCLUSIONS: A single soft marker is commonly encountered during the second trimester among fetuses with trisomy 21. The risk of fetal Down syndrome, reflected by likelihood ratios, was determined for 6 individual markers. This information can be combined with the a priori risk to estimate the individual patient risk for fetal Down syndrome.     

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.     

The genetic sonogram: a method of risk assessment for Down syndrome in the second trimester.

OBJECTIVE: To determine the risk of Down syndrome in fetuses with sonographic markers using the Bayes theorem and likelihood ratios. METHODS: We prospectively evaluated the midtrimester sonographic features of fetuses with Down syndrome and compared them with euploid fetuses. Patients were referred for an increased risk of aneuploidy and evaluated for the presence of structural defects, a nuchal fold, short long bones, pyelectasis, an echogenic intracardiac focus, and hyperechoic bowel. All fetuses underwent amniocentesis at the time of sonographic assessment. The sensitivity, specificity, and likelihood ratios for markers were calculated both as nonisolated and isolated findings. RESULT: There were 164 fetuses with Down syndrome and 656 euploid fetuses. The presence of any marker resulted in sensitivity for the detection of Down syndrome of 80.5% with a false-positive rate of 12.4%. The absence of any markers conferred a likelihood ratio of 0.2, decreasing the risk of Down syndrome by 80%. As an isolated marker, the nuchal fold had an "infinite" likelihood ratio for Down syndrome; a short humerus had a likelihood ratio of 5.8, whereas structural anomalies had a likelihood ratio of 3.3. Other isolated markers had low likelihood ratios because of the higher prevalence in the unaffected population. The likelihood ratios for the presence of 1, 2, and 3 of any of the markers were 1.9, 6.2, and 80, respectively. CONCLUSIONS: Although an isolated marker with a low likelihood ratio may not increase a patient's risk of Down syndrome, the presence of such a marker precludes reducing the risk of aneuploidy. Clusters of markers appear to confer a higher risk.     

Isolated echogenic foci in the fetal heart as marker of chromosomal abnormality.

OBJECTIVE: To assess the effect of echogenic foci in the fetal heart on the risk for Down's syndrome. DESIGN: Prospective evaluation of fetal echocardiograms at a fetal cardiology referral center and systematic postnatal follow-up. A relative risk was calculated from the prevalence of echogenic foci in fetuses subsequently demonstrated to have trisomy 21 divided by that in normal fetuses. For a subgroup of 548 fetuses with echogenic foci but otherwise normal detailed anomaly scans, the expected number of trisomy 21 fetuses calculated from maternal age risks was compared with the observed number to derive a relative risk for isolated echogenic foci. RESULTS: Echogenic foci occurred in 905 of 6904 fetuses scanned, but after excluding those referred specifically because of an echogenic focus and those with heart defects, the incidence was 9.5%. Overall, echogenic foci were more frequent in fetuses with trisomy 21 than those without by a factor of 2.93. For the 548 fetuses with echogenic foci but otherwise normal detailed anomaly scans, the actual number of trisomy 21 fetuses exceeded that expected on the basis of maternal age risks by a factor of 5.54. Combination with data from several previous studies suggests a consensus relative risk of about 3.0. CONCLUSIONS: Echogenic foci are associated with increased risk of trisomy 21 even when present as an isolated finding. Their significance in an individual should be interpreted in the light of prior risk assessment based on maternal age and results of any first-trimester screening tests. We suggest that the prior risk is increased by a factor of 3.0.     

Choroid plexus cyst, intracardiac echogenic focus, hyperechogenic bowel and hydronephrosis in screening for trisomy 21 at 11 + 0 to 13 + 6 weeks.

OBJECTIVES: To investigate the potential value of choroid plexus cyst, intracardiac echogenic focus, hydronephrosis and hyperechogenic bowel as markers of trisomy 21 at 11 + 0 to 13 + 6 weeks. METHODS: We examined three-dimensional volumes from 228 fetuses with trisomy 21 and 797 chromosomally normal fetuses at 11 + 0 to 13 + 6 weeks of gestation. We looked for choroid plexus cysts with a minimum diameter of 1.5 mm, intracardiac echogenic focus, hydronephrosis with a minimum anteroposterior diameter of the pelvis of 1.5 mm and hyperechogenic bowel. RESULTS: The prevalence of intracardiac echogenic focus, hydronephrosis and hyperechogenic bowel was significantly higher in trisomy 21 than in normal fetuses (9.6% vs. 1.5%, 17.1% vs. 5.3% and 11.4% vs. 2.4%, respectively). There was no significant difference between the two groups in the prevalence of choroid plexus cysts (7.5% vs. 5.0%). There were no significant differences in crown-rump length or nuchal translucency thickness in either chromosomally normal or trisomy 21 fetuses between those with and those without any one of the markers. CONCLUSIONS: At 11 + 0 to 13 + 6 weeks the prevalence of intracardiac echogenic focus, hydronephrosis and hyperechogenic bowel is higher in trisomy 21 than in chromosomally normal fetuses. As there is no significant association between the presence of these markers and nuchal translucency thickness, they could be included in the assessment of risk to improve accuracy of screening.     

Fetal intracardiac echogenic foci: does it matter which ventricle?

We sought to determine whether an association exists between the location of intracardiac echogenic foci and fetal aneuploidy or structural cardiac lesions. A search of the English language literature since 1980 revealed nine studies reporting location of intracardiac echogenic foci, fetal chromosomal abnormalities, and cardiac anomalies. Aneuploidy was noted in 10 of 217 fetuses with left ventricular and in one of 18 with right ventricular intracardiac echogenic foci. Three of 11 fetuses with biventricular intracardiac echogenic foci were aneuploid, which is significantly more frequently than when intracardiac echogenic foci were present in either ventricle alone (P = 0.02). There were nine cases of trisomy 21, four of trisomy 13, and one of trisomy 18. Structural cardiac lesions were recognized in eight of 217 fetuses with left ventricular foci, two of 18 with right ventricular foci, and one of 11 with biventricular intracardiac echogenic foci (P = 0.16). Biventricular intracardiac echogenic foci are more frequently associated with fetal aneuploidy but not structural lesions, as compared to isolated left or right ventricular intracardiac echogenic foci.     

Significance of an echogenic intracardiac focus in fetuses at high and low risk for aneuploidy.

Our objective was to evaluate the significance of an echogenic intracardiac focus in a mixed population of fetuses at high and low risk for aneuploidy. Over a 1 year period, we prospectively identified all fetuses with an echogenic intracardiac focus seen during prenatal sonography. A detailed structural evaluation was performed on each fetus as permitted by gestational age. The location and number of foci were tabulated prospectively, as were associated abnormalities. Follow-up was obtained by review of the medical record. Of the 290 fetuses who had an echogenic intracardiac focus, 14 of them were aneuploid (4.8%). Of the 290 mothers, 125 women were aged 35 years or older and 165 women were younger than 35 years old. Among the 125 fetuses born to women 35 years or older, eight were aneuploid fetuses (6.4%), while among the 165 fetuses of younger mothers, six were aneuploid fetuses (3.6%) (rate ratio = 1.8; 95% confidence interval [extremes] = 0.6, 4.9). Only one of the 14 aneuploid fetuses had an echogenic intracardiac focus as the only sonographic finding, and this occurred in a woman aged 41 years. The majority of the echogenic intracardiac foci (87.6%) were located in the left ventricle, while 4.8% of the foci were right-sided and 7.6% were bilateral. Among the 14 aneuploid fetuses, 14% had bilateral echogenic intracardiac foci and 7% had right-sided foci. Among the euploid fetuses, 7.3% had bilateral echogenic intracardiac foci and 4.7% had right-sided foci. In conclusion, we have shown that the presence of an echogenic intracardiac focus does raise the risk that the fetus has a chromosomal abnormality, most commonly Down syndrome, although all but one aneuploid fetus in our study had other sonographic findings.     

Are Intracardiac Echogenic Foci Markers of Congenital Heart Disease in the Fetus With Chromosomal Abnormalities?

OBJECTIVE: To determine whether intracardiac echogenic foci (ICEF) are markers of congenital heart disease (CHD) in fetuses with chromosomal abnormalities. METHODS: We identified all fetuses with chromosomal abnormalities undergoing targeted sonography at 17 weeks' to 21 weeks 6 days' gestation in a single perinatal center from January 1, 1994, to June 30, 2003. Offspring with and without CHD were compared for the presence or absence of ICEF. RESULTS: Two (8%) of 25 fetuses with ICEF had CHD versus 38 (33.3%) of 114 fetuses without ICEF (P = .006). Similarly, 1 (5.5%) of 18 fetuses with trisomy 21 and ICEF had CHD compared with 16 (37.2%) of 43 fetuses with trisomy 21 without ICEF (P = .009). CONCLUSIONS: Intracardiac echogenic foci in fetuses with chromosomal abnormalities, including those with trisomy 21, are not useful markers for CHD.     

Echogenic Intracardiac Foci

Objective. The purpose of this study was to evaluate the impact of an echogenic intracardiac focus (EIF) on the risk for fetal trisomy 21 (T21) in populations with differing prevalence of T21. Methods. A retrospective cohort study of pregnancies presenting to our prenatal ultrasound units over 16 years (1990–2006) was conducted. Contingency table analysis of the presence of an EIF and diagnosis of fetal T21 was performed. The groups analyzed included the following: (1) all fetuses with EIF plus other sonographic markers, (2) EIF as an isolated sonographic marker, (3) those younger than 35 years with an isolated finding of EIF, and (4) a group with an isolated finding of EIF excluding those at increased risk for T21 on serum screening. Results. Echogenic intracardiac foci were found in 2223 of 62,111 pregnancies (3.6%), and T21 was diagnosed in 218 pregnancies (0.4%). The presence of an EIF along with other markers was associated with a statistically significant risk for T21 (positive likelihood ratio [LR], 4.4; 95% confidence interval [CI], 3.2–6.0; P < .05). An isolated EIF was not associated with a statistically significant increased risk for T21 in patients younger than 35 years (positive LR, 1.7; 95%, CI 0.7–4.1) and those without abnormal serum screening results for aneuploidy (positive LR, 1.6; 95% CI, 0.8–3.1). Conclusions. The finding of an isolated EIF on prenatal sonography does not significantly increase the risk for fetal T21 in populations not otherwise at an increased risk for the disorder. An isolated EIF should be considered an incidental finding in patients younger than 35 years and in those without abnormal serum aneuploidy screening results.     

The value of single umbilical artery in the prediction of fetal aneuploidy: findings in 12,672 pregnant women

OBJECTIVES: To assess the risk of the association of single umbilical artery and aneuploidies. METHODS: In a general unselected obstetric population of 12,672 singleton pregnant women from January 1998 to December 2002, we detected 61 fetuses (prevalence, 0.48%) with single umbilical artery (SUA) on prenatal ultrasound at 16 to 23 menstrual weeks. RESULTS: Among the 61 fetuses with 2-vessel cord, 39 (64%) had SUA as an isolated finding, and 22 (36%) had additional findings, either minor or major. One (2.56%) of the 39 fetuses with SUA as an isolated finding had aneuploidy (trisomy 21 at maternal age of 32 years), whereas 5 (41.6%) of the 12 fetuses with SUA concomitant with major anomalies were aneuploid. None of the 10 fetuses with SUA and minor anomalies had aneuploidy. Among the 12,611 women with 3-vessel cord, we instead found 8 cases of trisomy 21 (0.06%), 1 case of translocation 14-21 (0.007%), 5 cases of trisomy 18 (0.04%), 1 case of trisomy 13 (0.007%), 1 case of 47,XXX (0.007%), and 2 cases of monosomy X (0.01%). CONCLUSIONS: In an unselected population, second trimester sonographic detection of SUA and major fetal anomalies indicate increased risk for fetal aneuploidy. However, even if this study is based on a large population, the only 1 case of trisomy 21 among the fetuses with SUA as an isolated finding is not sufficient to draw a conclusion, and larger studies are needed to confirm or infirm this single case.     

Fetal intracardiac echogenic foci: visualization depends on the orientation of the 4-chamber view.

OBJECTIVE: To compare the frequency of visualization of echogenic intracardiac foci in different cardiac views. METHODS: Women having ultrasonographic examinations between October 1997 and July 1998 were prospectively evaluated if a fetal echogenic intracardiac focus was seen in either ventricle. RESULTS: Echogenic intracardiac foci were seen in 89 fetuses in whom both the apical and lateral 4-chamber heart views were obtained. Eight-six fetuses (97%) had a single focus (83 in the left ventricle and 3 in the right ventricle), and 3 (3%) had 2 foci. Echogenic intracardiac foci were seen in the apical 4-chamber view in 89 (100%) and in the lateral 4-chamber view in only 26 (29%; P = .001). CONCLUSIONS: Echogenic intracardiac foci are not easily seen in the lateral 4-chamber view. Studies that suggest an increased risk of aneuploidy when echogenic foci are seen should specify the orientation of the 4-chamber view used.     

Sonographic markers of fetal trisomies: second trimester.

OBJECTIVE: Second-trimester sonographic findings of fetal trisomy may include structural abnormalities or sonographic markers of fetal aneuploidy. Unlike structural anomalies, sonographic markers of fetal aneuploidy are insignificant by themselves with regard to outcome, are nonspecific--most frequently seen in normal fetuses, and are often transient. Our objective was to review the second-trimester sonographic findings of the major trisomic conditions, trisomies 13, 18, and 21. METHODS: We reviewed a number of the most commonly accepted markers, including nuchal thickening, hyperechoic bowel, echogenic intracardiac focus, renal pyelectasis, shortened extremities, mild cerebral ventricular dilatation, and choroid plexus cysts. Markers associated with trisomy 21 were emphasized. RESULTS: The sensitivity of sonography for detection of fetal trisomic conditions varies with the type of chromosome abnormality, gestational age at the time of sonography, reasons for referral, criteria for positive sonographic findings, and the quality of the sonography. As an estimate, 1 or more sonographic findings can be identified in approximately 90% of fetuses with trisomy 13, 80% of fetuses with trisomy 18, and 50% to 70% of fetuses with trisomy 21 (Down syndrome). CONCLUSIONS: The presence or absence of sonographic markers can substantially modify the risk of fetal Down syndrome and is the basis of the so-called genetic sonogram. Because maternal biochemical and sonographic markers are largely independent, combined risk estimates will result in even higher detection rates than either alone.     

Ultrasonographic markers for chromosomal abnormalities in women with negative nuchal translucency and second trimester maternal serum biochemistry.

OBJECTIVE: To analyze the value of second trimester ultrasound examination among those women whose fetuses were indicated to be at low risk of chromosomal anomalies on the basis of both first trimester nuchal translucency measurement and second trimester biochemical screening. METHODS: A retrospective study of 5500 pregnancies carried out at the fetal medicine unit, Royal Free Hospital. During a period of over 3 years 5500 pregnancies underwent a first trimester scan and nuchal translucency measurement which enabled the detection of 62% (20 of 32) of all chromosomal anomalies. From the remaining pregnancies that underwent second trimester biochemical screening, 3548 were considered negative (risk < 1:250; using maternal serum free beta human chorionic gonadotrophin and alpha fetoprotein). The ultrasound markers that were examined were: shortened femur length, echogenic bowel, pyelectasis, choroid plexus cysts and echogenic intracardiac foci. The likelihood ratios for chromosomal aneuploides for each of these markers were calculated. RESULTS: Of the 3548 screen negative pregnancies, 3541 (99.8%) had a normal karyotype. Seven (0.2%) fetuses had an abnormal karyotype including four (0.11%) with trisomy 21, one with trisomy 18 and two with 47XXY. Second trimester ultrasound markers were found in two of the five (40%) with severe chromosomal anomalies compared to 184 of 3541 (5.2%) with normal karyotypes. Detection of one or more ultrasound markers in a screen negative pregnancy increased the possibility of chromosomal aneuploidy and a negative ultrasound decreased the risk by a likelihood ratio of 0.6 (95% confidence interval, 0.3-1.3). The risk was considerably increased when two or more markers were detected and we would recommend karyotyping under these circumstances. CONCLUSION: This preliminary data indicates a possible role for abnormal ultrasound markers in assessing the risk of chromosomal abnormalities in patients considered to be at low risk by nuchal translucency and serum screening. However analysis of a much larger study group will have to be conducted to assess the significance of individual markers.     

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.     

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.     

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.     

超声心动图对胎儿心脏强回声结构的检测及其心功能评价

目的 探讨超声心动图检测胎儿心脏强回声结构(intracardiac hyperechogenic focus,ICEF)及对ICEF胎儿心功能评价的临床意义.方法 采用胎儿超声心动图对1291例孕22～40周胎儿进行检测,对检出的ICEF胎儿测量心脏大小及室壁厚度,定量主动脉瓣口、肺动脉瓣口、房室瓣口血流速度,测量房室瓣环舒张早期、舒张晚期及收缩期运动的峰值速度(Em、Am、Sm);随机选择128例正常胎儿作为对照组并测量相关参数;比较单纯ICEF胎儿与正常胎儿间的心脏收缩及舒张功能参数.结果 共检出ICEF胎儿448例,检出率34.7%(448/1291),其中伴先天性心血管畸形24例(5.4%),轻度三尖瓣反流24例(5.4%),染色体异常1例(0.22%).399例单纯ICEF胎儿与正常胎儿之间比较,二维及M型超声心动图所测心脏大小及室壁厚度等参数差异均无统计学意义(P＞0.05),单纯性ICEF胎儿与正常胎儿之间比较,主动脉瓣口、肺动脉瓣口、房室瓣口血流流速曲线及房室瓣环运动速度参数差异均无统计学意义(P＞0.05).结论 单纯性的ICEF胎儿伴发染色体异常的几率较低,并不伴明显血流动力学改变.     

Is an isolated fetal cardiac echogenic focus an indication for fetal echocardiography?

OBJECTIVE: To determine whether the presence of an isolated fetal cardiac echogenic focus should be an indication for fetal echocardiography. METHODS: We reviewed our fetal echocardiography and obstetrics databases from January 1992 through July 1999. The study groups were formulated from patients referred for fetal echocardiography. Patients referred for echocardiography because of a single isolated fetal cardiac echogenic focus were compared with patients referred for other indications. The sensitivity, specificity, and positive and negative predictive values were calculated for an isolated echogenic focus as a marker for structural cardiac abnormalities as detected by fetal echocardiography. RESULTS: Of 10,406 fetuses seen for ultrasonography, 1908 had fetal echocardiography. Cardiac abnormalities were identified in 3.4% (65 of 1908) of the fetuses that had echocardiography. The prevalence of an isolated echogenic focus was 2.2% (230 of 10,406) and was the indication in 12.1% (230 of 1908) of our echocardiograms. Only 1 of the 230 fetuses with an isolated echogenic focus had a structural cardiac defect (membranous ventricular septal defect). An isolated echogenic focus as a marker for congenital cardiac defects resulted in sensitivity and specificity of 1.5% and 87.6%, respectively. The positive and negative predictive values were 0.4% and 96.2%, respectively The relative risk for an echogenic focus in predicting congenital cardiac defects was 0.11 (95% confidence interval, 0.02-0.82). CONDUSIONS: An isolated fetal cardiac echogenic focus is not an efficacious marker for congenital cardiac defects. It should not be the sole indication for fetal echocardiography.     

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.     

Second‐Trimester Genetic Sonography After First‐Trimester Combined Screening for Trisomy 21

Objective. The purpose of this study was to evaluate the trisomy 21 screening performance of the first‐trimester combined test followed by second‐trimester genetic sonography. Methods. This retrospective cohort study included all women with singleton pregnancies undergoing combined screening followed by genetic sonography at 17 to 21 weeks from January 1, 2005, to January 31, 2008. Combined test trisomy 21 risks were multiplied by positive or negative likelihood ratios based on the second‐trimester sonographic findings to determine the final trisomy 21 risk. Sonography was evaluated as the second part of (1) a stepwise sequential test applied to combined screen‐negative pregnancies and (2) an integrated test applied to all combined screen patients regardless of the latter results. A final trisomy 21 risk of 1:270 or higher was considered screen‐positive. Results. A total of 2231 pregnancies underwent combined screening, which detected 7 of 8 Down syndrome cases (87.5%) at a 9.6% screen‐positive rate. A total of 884 of these patients (39.6%), including 2 having fetuses with Down syndrome, had genetic sonography. Combined screening detected 1 of these trisomy 21 fetuses (50%) at a 15.7% screen‐positive rate. Integrated ultrasound‐based aneuploidy screening detected both trisomy 21 cases (100%) at a 22.7% screen‐positive rate, whereas stepwise sequential ultrasound‐based aneuploidy screening also detected both trisomy 21 fetuses (100%) but at a 28.3% screen‐positive rate (P < .0001). Conclusions. Second‐trimester genetic sonography after first‐trimester combined screening may improve trisomy 21 detection at the expense of increasing screen‐positive rates.