Biometry of the fetal heart between 10 and 17 weeks of gestation

OBJECTIVES: Assessment of the dimensions of the cardiac chambers and the great arteries in the human fetus may be helpful in the prenatal diagnosis of congenital heart disease. The purpose of this prospective cross-sectional study was to compile normative data in fetal cardiac measurements in early pregnancy. The structure of the fetal heart was examined in 136 normal singleton fetuses between 10 and 17 weeks of gestation. METHODS: The transversal heart diameter, both ventricular dimensions, interventricular septal thickness, heart area, heart circumference, thoracic diameter, thoracic circumference and thoracic area were measured in the four-chamber view during diastole. Diameters of the pulmonary trunk and ascending aorta were obtained in the short axis and long axis view during systole. Ultrasound examinations were performed with a 5.0-MHz transvaginal and/or transabdominal phased-array sector scanner. RESULTS: The four-chamber view and the cross-over of the pulmonary artery and the aorta were adequately visualized in 44% of the fetuses at 10 weeks of gestation, in 75% at 11 weeks of gestation, in 93% at 12 weeks of gestation and in 100% of the fetuses at 13-17 weeks of gestation. Before 14 weeks of gestation transvaginal sonography was superior to the transabdominal sonography in visualization of the fetal heart and great arteries. After 14 weeks of gestation transabdominal sonography accurately demonstrated the structure of the fetal heart. The ratio of right and left ventricle (RV/LV) and the ratio of the pulmonary trunk and aorta (PT/AO) were constant during this period of gestation (approximately 1.00 and 1. 10, respectively). The ratio of the cardiac and thoracic area showed only a slight increase with advancing gestational age, but with significant correlation. The fetal heart rate showed a slow decrease from 167 to 150 bpm in this period of gestation. The transversal heart diameter, both ventricular dimensions, interventricular septal thickness, heart area, cardiothoracic diameter ratio, aortic diameter and the pulmonary trunk diameter showed a highly significant linear correlation to the gestational age and the biparietal diameter. CONCLUSION: The advancing quality of ultrasound images allows fetal echocardiography in the first and early second trimester. Our normative data could be the basis of studying the development of cardiac structures in congenital heart disease and it might be helpful in the detection of some congenital heart defects in early pregnancy.     

妊娠10至17周胎儿四腔心的超声检测研究

目的 研究妊娠10至17周正常胎儿心脏四腔结构,为早期宫内诊断胎儿心脏异常提供帮助。方法 应用彩色多谱勒超声检测137例孕10至17周的正常胎儿心脏四腔结构。结果 ①孕10周可探测到44％胎儿心脏腔图孕13周以后均能探测到心脏四腔图;②左右心室的内径、心脏的横径、心脏面积、室间隔厚度与孕周呈高度正相关。③右左心室内径之比为1;④心胸比例随孕周轻度增加,此孕期心脏占据胸腔面积的1/5～1/4。而不是孕晚期的1/3。结论 孕13周至17周胎儿心脏的左右心室基本均匀发展,未呈现右心优势现象;心胸比例小于孕晚期;应用高分辨率的超声仪在此期可以探测到胎儿四腔心,有助于早期诊断胎儿心脏异常。     

The possibility of evaluation of the myocardial performance index in fetuses at 11,0 to 13,6 week of gestation

OBJECTIVES: To assess myocardial performance index (Tei index) for left and right ventricle in fetuses at 11.0 to 13.6 week of gestation. MATERIAL AND METHODS: Flow velocity waveforms of mitral, tricuspid, aortic and pulmonary valves were obtained. The Tei index for the left ventricle (Tei LV) was calculated in 55, and for the right ventricle (Tei RV) in 27 fetuses. RESULTS: The value of Tei LV ranged from 0.28 to 0.59, mean 0.41 +/- 0.08, and for Tei RV from 0.23 to 0.56, mean 0.37 +/- 0.11. There was no statistically important correlation either between Tei index and both ventricles or gestational age and fetal heart rate. The possibility to measure Tei index increased with the progress of the pregnancy. There remains a significant correlation between Tei LV and Tei RV values. CONCLUSIONS: Tei index may be useful for the assessment of fetal myocardial performance in the first trimester of pregnancy. Tei index is independent of gestational age and fetal heart rate. It is easier to measure the Tei index for the left ventricle than for the right one.     

Prenatal diagnosis of bilateral diaphragmatic hernia by fetal sonography

This report describes a case of prenatally diagnosed bilateral diaphragmatic hernia. At 22 weeks' gestation, ultrasound revealed a cystic structure behind the fetus's heart on the axial image at the level of the cardiac four-chamber view. This suggested a left-sided congenital diaphragmatic hernia with herniation of the stomach into the left hemithorax. However, the left-to-right midline shift of the heart was minimal, which is not typical of left-sided congenital diaphragmatic hernia. Throughout the 30th week of gestation, the right and left branches of the pulmonary artery were hypoplastic compared with the values in normal fetuses of the same gestational age. The presumptive diagnosis was bilateral congenital diaphragmatic hernia. A female newborn weighing 2900 g was delivered at 37 weeks' gestation, and she died at 7 h of age. An autopsy revealed large defects on both sides of the diaphragm. In conclusion, prenatal diagnosis of bilateral diaphragmatic hernia is possible with fetal sonography.     

Fetal left ventricular diverticulum presenting as dysrhythmia: diagnosis and management

Congenital diverticulum of the left ventricle is a malformation, often associated with midline thoraco-abdominal defects. Here we describe a case of isolated congenital left ventricular diverticulum that presented with an abnormal four-chamber view and fetal dysrhythmia on ultrasonography. Maternal digoxin therapy was started due to significant ventricular ectopy. Restoration of fetal sinus rhythm was achieved within 48 h. Serial fetal echocardiograms were performed every week, followed by a normal vaginal delivery at term. The child is surviving at 1 year of age.     

应用Tei指数评价胎儿心室功能的研究

目的探讨正常胎儿左、右心室的Tei指数在评价胎儿心脏收缩和舒张功能中的作用及其影响因素。方法应用多普勒超声心动图检查妊娠18~42周的正常单胎胎儿225例,按孕周不同分为18~27周+6组、28~36周+6组和37~42周组,测定3组胎儿左、右心室的Tei指数的差异,并比较左、右心室Tei指数,探讨其与孕周和胎心率的关系。结果(1)妊娠18~27周+6、28~36周+6和37~42周3组胎儿的左心室平均Tei指数分别为0·37±0·08、0·27±0·05、0·22±0·05;右心室平均Tei指数分别为0·39±0·04、0·30±0·05、0·24±0·04。妊娠28~36周+6组右心室平均Tei指数高于左心室,两者比较,差异有统计学意义(P<0·05)。其余两组左、右心室平均Tei指数比较,差异无统计学意义(P>0·05)。(2)正常胎儿左、右心室的Tei指数均显示随着孕周的增加呈逐渐下降的趋势,与孕周呈负相关(左心室r=-0·755,P<0·01;右心室r=-0·721,P<0·01)。(3)正常胎儿Tei指数与胎心率无相关性(左心室r=0·133,P>0·05;右心室r=0·100,P>0·05)。结论Tei指数是一种方便、有效的综合评价胎儿心脏收缩和舒张功能的指标。     

三个心脏超声切面在常见先天性心脏病产前诊断中的作用

目的 探讨三个胎儿超声心动图标准切面：四腔心切面、五腔心切面、三血管平面在发现和诊断胎儿常见先天性心脏病中的作用及对于先天性心脏病产前筛查的意义。方法 回顾2003年5月至2004年7月胎儿心脏畸形各病例的心脏超声图像，记录每一病例三个超声切面（四腔心切面、五腔心切面、三血管平面）的彩色多普勒超声图像表现，分析并总结各切面异常表现的特点。结果 （1）研究共包括胎儿心脏畸形病例26例，疾病类型包括房室间隔缺损、单纯性室间隔缺损、单心室、单心房、左心发育不良综合征、法洛四联症、右心室双出口、纠正性／完全性大动脉转位、动脉单干、主动脉瓣狭窄、肥厚性心肌病（梗阻型）、心脏肿瘤。（2）各心脏畸形病例在这三个心脏超声切面的扫查中至少有1个切面显示异常。每一类心脏畸形在这三个切面图像上均有特征性表现。（3）所有病例中二维四腔心切面（常规产科筛查切面）显示异常的比例为73％，四腔心切面未显示异常的病例包括：完全性大血管转位3例、法洛四联症1例、右心室双出口1例、动脉单干1例、主动脉骑跨伴室间隔缺损1例。（4）各标准切面获得率分别为：96．2％、88．5％、84．6％。结论 （1）四腔心切面、五腔心切面、三血管平面这三个胎儿彩色多普勒心脏超声切面探查在各类胎儿常见的先天性心脏病超声产前检查与诊断中起重要的作用。（2）与运用单个二维四腔心切面探查比较，三个切面的探查方法可提高常见先天性心脏病，尤其是胎儿心脏锥干畸形的检出率。（3）三个切面探查操作较为简便，有望成为一项胎儿先天性心脏病的筛查方法。     

Transvaginal fetal echocardiography in early pregnancy: normative data

Fifty-two transvaginal ultrasonographic examinations were performed between 10.0 and 14.9 weeks' gestation for the purpose of documenting normal fetal cardiac anatomy. All standard cardiac projections could be obtained by gestational week 12, and many were imaged by week 11. The four-chamber view was visualized in 90% of fetuses at 12 weeks' gestation and in 100% of fetuses examined at 13 weeks. The aortic root in short axis projection and the left ventricle in long axis view could be imaged in 70% and 40% of fetuses, respectively, by 12 weeks' gestation. Aortic and pulmonary valves were first visualized at 12 weeks, as were five-chamber, ductus arteriosus, and aortic arch views. The mitral and tricuspid valves were resolved in 60% of fetuses by 11 weeks' gestation. This study of normal cardiac anatomy suggests that there may be significant potential for the diagnosis of many fetal cardiac anomalies during the late first and early second trimesters of pregnancy.     

Fetal cardiac asymmetry: a marker for congenital heart disease

Objective: To determine the sensitivity of prenatally detected fetal cardiac asymmetry as a sonographic marker for congenital heart disease.Methods: The normal ratios of pulmonary artery to aorta diameters and of right ventricle to left ventricle diameters were derived from normal fetuses scanned at 17 weeks or more in a 65-month period. Cross-sectional diameters of cardiac ventricles and great arteries were measured at the level of the valves at the time of the scan. Fetuses with confirmed cardiac anomalies detected prenatally during the study were examined to identify how many had cardiac asymmetry, determined by abnormal ratios.Results: Linear regression analysis of the group of 881 normal fetuses showed the normal pulmonary artery to aorta diameter ratio remained constant throughout pregnancy and the normal right ventricle to left ventricle ratio increased slightly with progressing gestational age. The 90% confidence intervals were 0.79, 1.24 for the right ventricle to left ventricle ratio and 0.84, 1.41 for the pulmonary artery to aorta ratio. Of the 73 fetuses with abnormal hearts, 66% had either ventricular or great artery asymmetry (at least one of the two ratios was abnormal). However, if no asymmetry was present, the cardiac defect was more likely to be a minor one.Conclusion: Cardiac asymmetry was present in two-thirds of fetuses with cardiac anomalies diagnosed prenatally. If cardiac asymmetry is found, a more thorough examination of the fetal heart is indicated.     

Evaluation of fetal cardiac contractility by two-dimensional ultrasonography

OBJECTIVE: Evaluation of fetal cardiac contractility by two-dimensional ultrasonography and construction of nomograms of area shortening fraction, end-diastolic area and end-systolic area of fetal cardiac ventricles during uncomplicated pregnancy. MATERIALS AND METHODS: Fetal echocardiography was performed on 160 pregnant women between 14 and 28 weeks' gestation. Measurements were taken on the four-chamber view. The area of each ventricle was measured by tracing the endocardium at the end of systole and at the end of diastole. Area shortening fraction was calculated by the following formula: SF = (Ad - As)/Ad (SF--area shortening fraction, Ad--end-diastolic ventricular area, As--end-systolic ventricular area). RESULTS: A statistically significant increase in normal fetal area shortening fraction, end-diastolic area and end-systolic area of both ventricles with advancing gestational age was established. There were no significant differences in the area shortening fraction between right and left ventricles. CONCLUSIONS: Area shortening fraction shows good correlation with gestational age. Nomogram of area shortening fraction, end-diastolic area and end-systolic area of both ventricles can be used as the reference for evaluation of ventricle size and cardiac contractility in normal and pathological cases.     

Evaluation of the human fetal cardiac size and function

Two-dimensional-directed M-mode echocardiography was done on 80 normal fetuses between the 17th to 42nd weeks of gestation. The M-mode beam transected the ventricles at the level of the chordae tendineae at the tip of atrioventricular valves. Right and left ventricular dimensions and free wall thicknesses correlated well with gestational age. Calculated measurements showed a good correlation of the stroke volume and cardiac output with gestational age. The right ventricular dimension, however, was significantly greater than the left ventricular one. Fractional shortening of the right and left ventricle did not change significantly with advancing gestational age. This study indicates that the human fetal right ventricle dimension, stroke volume, and cardiac output are slightly larger than that of the left ventricle. This study also suggests that the human fetus increases its cardiac output to match its growth and it does so by increasing ventricular size rather than fractional shortening or heart rate.     

Fetal congestive heart failure: correlation of Tei-index and Cardiovascular-score.

INTRODUCTION: Congestive heart failure (CHF) may be present in fetuses with hydrops fetalis (HF) and the severity is difficult to quantitate. Differential ventricular dysfunction may be present in the fetus with CHF. A non-geometric measure of ventricular function that is not afterload dependent would be useful to measure the severity of myocardial dysfunction. METHODS: Tei-index (isovolumetric time/ejection time) was measured prenatally in 23 normals (24-34 weeks gestational age-GA) and in 7 with HF (24-34 weeks GA). Prenatal CHF severity was graded by a 10 point cardiovascular (CV) score (2 points each for absence of hydrops, normal venous Doppler, heart function, arterial Doppler, and heart size, and 10/10 = normal). A paired student t-test was used to compare RV and LV and non-paired t-test compared HF and normals. Tei-index and CV score were correlated. RESULTS: Tei-index normals were 0.38 +/- 0.04 in the right ventricle (RV) and 0.41 +/- 0.05 in the left ventricle (LV) and there were no significant RV-LV or gestational age (GA) differences. Among HF fetuses, RV and LV Tei-indices were both significantly increased (0.54 and 0.92) and not significantly different. CV score ranged from 2 to 8 (mean 5.43 out of 10) and correlated inversely with Tei-index (r = -0.52, r = -0.68). CONCLUSION: Hydrops fetalis is associated with biventricular dysfunction and congestive heart failure. Tei-index correlates with CV score obtained within two weeks of delivery or intrauterine death. Tei-index may be useful in the serial assessment of myocardial dysfunction in the fetus with hydrops.     

Intracardiac echogenic focus and its location: association with congenital heart defects

Purpose: Significance of intracardiac echogenic focus (ICEF) in the fetal heart remains controversial. We aimed to investigate whether the location of ICEF is associated with fetal cardiac structure defects (CSDs) in low-risk pregnant women.

Materials and Methods: A retrospective cohort study was conducted. Singleton pregnancies with normal values of triple fetal serum markers were included. 758 of 9782 fetuses with ICEF were reviewed for involvement of three ICEF locations (left, right, and bilateral ventricles (BVs)) in CSDs. χ² or Fisher’s exact test was performed for statistical analysis.

Results: ICEF prevalence was 7.7% and its location was most frequently in the left ventricle (LV) (84.8%), followed by the BV (11.6%) and the right ventricle (RV) (3.6%). No statistically significant difference was found between the ICEF location and maternal age (χ²?=?3.92, p-value?=?.1409). There were cardiac defects with an isolated echogenic focus in 24 of 758 fetuses (3.2%). Significant difference for CSDs was observed among groups of RV, LV, and BV (p-fisher?=?.0146).

Conclusions: Significantly more CSDs cases were identified in fetuses with ICEF in RV. Further investigation is warranted to examine the histological characteristics of fetal echogenic focus in the RV.     

Combined Ventricular Shortening Fraction: An Echocardiographic Index of Fetal Systolic Cardiac Function

Fetal cardiac function was investigated using a two-dimensional directed M-mode measurement of combined ventricular shortening fraction (SF). From a four-chamber view, the M-line was directed perpendicular to the atrioventricular valves to obtain end-diastolic and systolic dimensions from RV anterior wall to LV posterior wall in 76 normal gestations (NL), 29 well-controlled diabetics (DM), and two hydropic fetuses with ventricular dysfunction. SF was inversely proportional to gestational age and heart size, but independent of heart rate and umbilical artery Doppler wave form (A/B). In NL, SF = 43 ± 5% (range 33–55) and was not significantly different from that in DM (SF = 43 ± 6%, range 30–56), even in the presence of abnormal A/B. Both fetuses who died in hydrops had decreased SF of 15 and 23%. SF is a practical tool to assess fetal systolic function and response to therapy.     

Ventricular dominance patterns in preterm infants

OBJECTIVE: The purpose of the study was to determine EKG and 2-D echocardiographic criteria of ventricular dominance in preterm infants and select those by which ventricular dominance could be established by EKG alone. METHODS: A database was constructed from EKG and 2-D echocardiographic measurements on preterm infants ranging in gestational ages from 23 to 34 weeks and birth weights from 555-2490 g, and fullterm controls. Twelve-lead EKGs were obtained in the first 4 days of life in 12 preterm infants and in the first 24 hours of 4 controls. 2-D echocardiograms were performed with sweeps from the subcostal, parasternal, apical and suprasternal views and M-mode measurements in the short axis parasternal view on 11 of the preterm infants and 9 fullterm controls. RESULTS: A definite leftward QRS axis for the preterm infants (+90 degrees, preterm; +133.75 degrees, term; t = -5.63; p < 0.001) indicated a left ventricular (LV) dominance. But R/S in favor of LV dominance for preterm infants was apparent in V6 only. A pooled amplitude index for each ventricle based on R and S wave from V1, V2, V5, and V6 leads, showed LV dominance for the preterm infants with a trend toward RV dominance with increasing gestational age (F = 20.82; p < 0.001). RVD/LVED M-mode echo ratios confirmed the LV dominance in preterm infants. CONCLUSION: A healthy full term infant is born with RV dominance. LV dominance with a trend toward RV dominance with increasing gestational age was found in preterm infants by EKG and echo criteria.     

Early prenatal diagnosis of major cardiac anomalies in a high-risk population

OBJECTIVE: To examine the accuracy of early fetal echocardiography performed in a high-risk population combining transvaginal and transabdominal routes. METHODS: A series of 330 high-risk pregnancies were screened by transvaginal and transabdominal scan at 12-17 weeks' gestation in a prospective multicentre trial in Spain between September 1999 and May 2001. A total of 334 fetal heart examinations were performed, including four twin pregnancies. Maternal age ranged from 17 to 46 years (mean 33 years with 36% of women over 34 years). The median gestational age at scan was 14.2 weeks (range 12-17 weeks). For each fetus, visualization of the four-chamber view, the origin of the great arteries, aortic and ductal arches and systemic venous return was attempted in a segmental approach. B-mode and colour/pulsed Doppler flow imaging were used in all cases. The duration of complete heart examination was less than 30 minutes. The examinations were performed by three experienced operators. Reliability was assessed by conventional transabdominal echocardiography at 20-22 weeks, by postnatal follow-up in the first three months of life, and/or by autopsy in cases of termination of pregnancy. RESULTS: The rate of successful visualization of the fetal heart was 94.6% (316/334). In 48 out of 334 (14.4%) fetuses the final diagnosis was abnormal. In 38 out of 48 (79.2%) cases with heart defects the diagnosis was suspected at early echocardiography. In the group with congenital heart defects, 27 cases had an abnormal karyotype (56.3%) and 31 cases showed extracardiac anomalies (64.6%). There were 10 false-negative cases at early scan. There were no false-positive diagnoses. CONCLUSIONS: This experience stresses the usefulness of early fetal echocardiography when performed by expert operators on fetuses specifically at risk for cardiac disease. The high rate of successful visualization of the fetal heart provides a reliable diagnosis of major cardiac defects at this early stage of pregnancy.     

Heart stroke volume,cardiac output,and ejection fraction in 265 normal fetus in the second half of gestation assessed by 4D ultrasound using spatio-temporal image correlation

Objectives.?The aim of this study was to establish nomograms for fetal stroke volume (SV), cardiac output (CO), and ejection fraction (EF) using four-dimensional ultrasound with spatio-temporal image correlation (STIC) modality.

Methods.?The fetal heart was scanned using STIC modality, starting with classic four-chamber view plane, during fetal quiescence with abdomen uppermost, at an angle of 20–30°, without color Doppler flow mapping. In post-processing virtual organ, computer-aided analysis technique was used to obtain a sequence of six sections of each ventricular volume in end-systolic volume (ESV) and end-diastolic volume (EDV). The SV (SV?=?EDV–ESV), CO (CO?=?SV?×?fetal heart rate), and EF (EF?=?SV/EDV) for each ventricle were then calculated. Intra- and interobserver agreement were then calculated.

Results.?Two hundred sixty-five fetuses, ranging in gestational age (GA) from 20 to 34⁺⁶ weeks, were included in the study. The left and right SV and CO increased exponentially with gestation and EF remained fairly stable through gestational. Mean left and right SV increased from 0.211?ml and 0.220?ml at 20 weeks to 1.925?ml and 2.043?ml, respectively, at 34 weeks. Mean left and right CO increased from 30.25 ml/min and 31.52 ml/min at 20 weeks to 268.49 ml/min and 287.80 ml/min, respectively, at 34 weeks. Both left and right mean EF remained constant at around 0.63 with advancing GA. Nomograms were created for LSV, RSV, LCO, RCO, LEF, and REF vs. gestational age. Intra- and interobserver agreement reached 95%.

Conclusions.?Four-dimensional ultrasound using STIC represents a simple and reproducible method for estimating fetal cardiac function. STIC seems to overcome many of the pitfalls of conventional ultrasound methods and has the potential to become the method of choice.     

Fetal echocardiography: accuracy and limitations in a population at high and low risk for heart defects.

OBJECTIVE: Our objective was to assess the accuracy of prenatal echocardiography in detecting congenital heart defects in patients at high and low risk for structural cardiac anomalies. STUDY DESIGN: Sixty-nine consecutive fetuses with congenital heart defects who had had prenatal ultrasonography at greater than or equal to 18 weeks' gestation were evaluated to determine the accuracy of prenatal ultrasonography in identifying structural cardiac defects. Thirty-nine patients were at high risk and 30 patients were at low risk for cardiac anomalies. All fetuses were scanned with standard four-chamber and outflow tract views. Data concerning extracardiac anomalies and karyotypic abnormalities were tabulated. The accuracy of the four-chamber view alone in identifying congenital heart defects was evaluated. RESULTS: Fifty-seven of 69 fetuses (83%) were prenatally identified ultrasonographically as having a heart defect. There was no difference in the sensitivity of detecting cardiac anomalies between high-risk and low-risk groups. When the four-chamber view was used, only 63% of fetuses were recognized as having an abnormal heart. Extracardiac anomalies were noted in 36% and karyotypic abnormalities in 17% of patients. CONCLUSION: The four-chamber and outflow tract views done routinely in an ultrasonography laboratory seeing a mixed population of patients was successful in detecting 83% of fetuses with structural cardiac malformations. Because 43% of the fetuses with heart defects were referred for low-risk indications, systematic ultrasonographic examination of the fetal heart should not be reserved only for those at high risk.     

Caliber of the coronary sinus in fetuses with cardiac defects with and without left persistent superior vena cava and in growth-restricted fetuses with heart-sparing effect

OBJECTIVE: To assess reference ranges for fetal coronary sinus (CS) diameter and to compare them with values from fetuses showing heart defects with and without left superior vena cava (LSVC) as well as with severe intrauterine growth retardation and heart-sparing effect on color Doppler. METHODS: The coronary sinus was visualized on two-dimensional ultrasound in a plane slightly caudal to the apical four-chamber view. For the normal range of the size of the CS in relation to gestational age, data was collected from 108/114 (95%) normal fetuses with good visualization between 20 weeks' gestation and term. Abnormal conditions comprised two groups: group 1 consisted of 52 fetuses with heart anomalies, including three subgroups: 11 fetuses with isolated LSVC emptying into the coronary sinus, 12 fetuses with LSVC associated with structural heart defects and 29 fetuses with structural heart defects but without LSVC. Group 2 consisted of 11 fetuses with severe intrauterine growth retardation and dilated coronary arteries as seen by color Doppler ultrasound. RESULTS: Under normal conditions, there was a significant increase in the CS diameter with advancing gestational age (1.2-2.7 mm). Significant dilatation was found only in the two groups with LSVC (range 2.7-6.5 mm), independent of whether the finding was isolated or associated with cardiac defects. CONCLUSION: CS visualization and measurements are easily feasible in the human fetus in the apical four-chamber view. Significant dilatation of the CS is a sign of LSVC. The examiner should be aware of this condition as such dilatation is commonly falsely diagnosed as atrial or atrioventricular septal defect.     

Utility of fetal echocardiogram in high-risk patients

AIM: Patients at high risk of fetal congenital heart disease are commonly referred for second trimester fetal echocardiogram. The objective of this study was to evaluate the utility of routine fetal echocardiogram in high-risk patients after the evaluation of the four-chamber/left ventricular outflow tract (LVOT) views during comprehensive second trimester anatomy ultrasound. METHODS: Second trimester comprehensive anatomy ultrasounds, which included a four-chamber/LVOT view, and subsequent fetal echocardiograms carried out at the Duke University Medical Center from January 1995 and July 2002 were reviewed. Those fetal echocardiograms carried out between 17 and 30 weeks gestation were included in the analysis. RESULTS: A total of 725 individual subjects met the inclusion criteria. Twenty-nine fetal echocardiograms were ultimately reported as abnormal. Of these, 19 had an abnormal four-chamber/LVOT view, four had a suboptimal view and six had a normal view. Of the six patients with a normal four-chamber/LVOT, all had been referred for echocardiogram based on the presence of other significant fetal anomalies noted at the time of second trimester anatomy ultrasound (3), documented aneuploidy (2), and significant fetal arrhythmia (1). CONCLUSION: Utility in carrying out fetal echocardiogram was seen in patients with an abnormal four-chamber/LVOT view, a suboptimal view in a high-risk patient, and the presence of other significant fetal abnormalities. Utility was not seen in patients with pre-existing diabetes mellitus.