Three-dimensional (3-D) ultrasonography for obtaining the four and five-chamber view: comparison with cross-sectional (2-D) fetal sonographic screening.

OBJECTIVES: To assess the ability of Doppler-gated 3-D fetal echocardiography to reconstruct and display specific cardiac structures routinely visualized during antenatal ultrasound in a population at low risk for cardiac anomalies. To determine whether any advantage is offered by 3-D sonographic cardiac examination over conventional sonographic fetal screening techniques. DESIGN: After routine two-dimensional sonographic examination, 3-D cardiac data were collected prospectively in 30 fetuses with gestational ages between 19 and 23 weeks from a low risk patient population. Basic echocardiographic key views were derived from 3-D data and selected for reconstruction and analysis. Four- and five-chamber views were rated and only those views judged to be well visualized were considered as positive results. RESULTS: The four- and five-chamber views were well visualized in all but one fetus using conventional 2-D imaging. Gated 3-D volume data sets enabled visualization of these structures in only 19 of 30 fetuses but provided additional structural depth and allowed a dynamic 3-D perspective of valvar morphology and ventricular wall motion. The right ventricular outflow tract was available from the 3-D volumes in 16 subjects. CONCLUSIONS: Considering the versatility of gated 3-D fetal cardiac imaging we believe that it may soon become an important component of fetal screening thus helping to retrieve standard cardiac cross sections when 2-D imaging is limited by lack of sonographer experience or sonographic windows. Diagnostically acceptable echocardiographic views were obtained more consistently with 2-D ultrasound than with 3-D volume data.     

A new approach to fetal echocardiography: digital casts of the fetal cardiac chambers and great vessels for detection of congenital heart disease.

OBJECTIVE: The purpose of this study was to describe a method of 4-dimensional (4D) reconstruction of the cardiac chambers and outflow tracts using a combination of spatiotemporal image correlation, "inversion mode," and "B-flow" imaging. METHODS: Spatiotemporal image correlation and the inversion mode were used in the examination of the volume data sets of 23 fetuses with congenital heart anomalies. A subset was also examined with B-flow imaging using the gradient light algorithm. Digital reconstructions from abnormal hearts were compared with a library obtained from fetuses without abnormalities. RESULTS: Rendered images of the 4-chamber view using the inversion mode were characterized by: (1) echogenic chambers; (2) sharp delineation of chamber contours when compared with 2-dimensional (2D) images; and (3) distinct display of the myocardium, interventricular septum, interatrial septum, and mitral and tricuspid valves as anechoic structures. Ventricular septal defects, abnormal differential insertion of the atrioventricular valves, and valve atresia were well visualized with the inversion mode. The application of inversion mode or B-flow imaging to 4D rendering of the outflow tracts resulted in "digital casts" displaying the spatial relationships between the outflow tracts as well as the connections between the great arteries and ventricular chambers. The spatial relationships and communications among cardiac structures cannot be visualized with conventional 2D ultrasonography. CONCLUSIONS: The application of spatiotemporal image correlation, inversion mode, and B-flow imaging generates information about the anatomy and pathologic characteristics of the fetal heart (digital casts) that cannot be obtained with 2D fetal echocardiography. We propose that these modalities enhance the information provided by ultrasonographic interrogation of the fetal heart and will improve prenatal diagnosis.     

Two- and four-dimensional echocardiography with B-flow imaging and spatiotemporal image correlation in prenatal diagnosis of isolated total anomalous pulmonary venous connection.

OBJECTIVES: To explore whether the use of four dimensional (4D) ultrasound examination with B-flow imaging and spatiotemporal image correlation (STIC) can supply additional information with respect to two-dimensional (2D) gray-scale and color Doppler echocardiography in the prenatal characterization of isolated total anomalous pulmonary venous connection (TAPVC). METHODS: The study population comprised a group of three TAPVC fetuses that had been examined exclusively by conventional echocardiography, and a group of four additional cases initially identified by conventional echocardiography and examined further by 4D ultrasonography; a thorough postnatal work-up was available for all fetuses. RESULTS: At our center, isolated TAPVC was found in seven of 1040 fetuses with cardiac defects (0.67%). Anomalous drainage was supracardiac to the innominate vein in three cases, cardiac to the coronary sinus in two, and infracardiac to the portal vein in the remaining two cases. An evident asymmetry between left heart and right heart structures was observed in 4/7 cases. The confluence of the anomalous pulmonary veins (PVs) was visualized in 4/7 cases and the connecting vertical vein was identified in 3/5 cases at 2D echocardiography. 4D ultrasound imaging with B-flow imaging and STIC clearly visualized the anomalous PV confluence and the draining vertical vein in all four cases examined. CONCLUSION: 2D and color Doppler echocardiography appears to diagnose reliably TAPVC, albeit with some limitations in thorough assessment of the pathology, depending on the anatomy of the defect, on the technical adequacy of the equipment used and on the experience of the operator. 4D ultrasound examination with B-flow imaging and STIC is apparently able to facilitate identification of the anatomical features of TAPVC, thus supplying additional information over that provided by 2D fetal sonography.     

Three-dimensional quantitative echocardiographic assessment of ventricular volume in healthy human fetuses and in fetuses with congenital heart disease.

The purpose of this study was to evaluate the feasibility of three-dimensional freehand echocardiographic assessment of ventricular volumetry in healthy fetuses and in fetuses with congenital heart disease. The study was approved by the hospital institutional review board. After echocardiographic examination by conventional ultrasonographic equipment interfaced with a magnetic tracking system, three-dimensional cardiac data were collected prospectively in 57 fetuses. Ventricular volumes were determined from three-dimensional data sets, and 22 fetuses with congenital heart disease were compared with 29 healthy fetuses. A multiple regression analysis of covariance was performed to assess between-group differences. Gated three-dimensional volume data sets enabled assessment of ventricular volumes in 51 of the 57 fetuses. Both fetuses with and without congenital heart disease had exponential increases in cardiac volumes during gestation. In fetuses with congenital heart disease and a marked inequality of ventricular size but no heart failure, the combined end-diastolic and stroke volumes of both ventricles were found to be significantly reduced compared with controls with no disease and fetuses with other types of congenital heart disease. Three-dimensional imaging can provide estimates of ventricular volume changes in fetal hearts with abnormal ventricular morphology that cannot easily be performed by two-dimensional echocardiography, and it may provide insight into evolving congenital heart disease.     

基于容积超声的胎儿心脏计算机辅助诊断技术获取胎儿超声心动图基本诊断切面的应用价值

目的:评价基于容积超声的胎儿心脏计算机辅助诊断(sonography based volume computer aided display heart,SonoVCADheart)技术在获取胎儿超声心动图基本诊断切面中的应用价值。方法:选取2019年1月8-22日在浙江大学医学院附属邵逸夫医院就诊的80例中晚孕单胎胎儿(57例心脏正常,23例心脏异常),使用容积探头快速采集4~5个以四腔心切面为基础切面的心脏四维容积数据。三位不同经验的医师(医师A:从事胎儿心脏超声诊断15年以上;医师B和C:经过正规胎儿超声心动图培训6个月但经验不丰富)分别采用SonoVCADheart分析处理,对诊断切面的要素化内容进行评分、诊断,并且计算成功率,然后进行统计分析。结果:57例正常胎儿共获取279个容积数据包,平均4.89个/胎儿;23例异常胎儿共获取109个容积数据包,平均4.74个/胎儿。所有容积数据均用于分析,8个诊断切面中所有要素均≥2分的容积百分比分别为:正常组70.61%~74.91%、异常组53.21%~55.96%。不同时间同一医师评分、经验不足医师之间评分及分别与经验丰富医师评分结果差异均无统计学意义(P>0.05);正常、异常组间的评分除了三位医师上下腔静脉-右心房切面以及医师A和C的主动脉弓切面外差异均有统计学意义(P<0.05);分析并完成诊断所需时间比较:医师A与医师B、C差异均有统计学意义(P<0.05),医师B和C差异无统计学意义(P>0.05);医师A采用SonoVCADheart诊断与二维超声诊断时间比较:异常组差异有统计学意义(P<0.05),正常组差异无统计学意义(P>0.05);异常组SonoVCADheart诊断符合率为89.91%~90.83%。结论:SonoVCADheart技术对于显示胎儿心脏的8个标准诊断切面具有较高的重复性及良好的稳定性,能够为胎儿超声心动图检查提供重要的关键的诊断切面,在图像采集和显示的标准化方面具有潜在临床应用价值。     

Transvaginal echocardiographic examination of the fetal heart between 13 and 15 weeks' gestation in a low-risk population.

The object of our investigation was to evaluate the potential of transvaginal echocardiography for a complete anatomic study of the fetal heart, and for detection of congenital heart diseases in low-risk pregnant patients between 13 and 15 weeks' gestation. High-frequency (6.5 MHz and 7.5 MHz) transvaginal probes were employed for fetal echocardiographic assessment. Six hundred and sixty patients considered at low risk for congenital heart disease underwent in utero ultrasonographic studies, neonatal records, postnatal imaging studies, and pathologic examination. The four-chamber view was obtained in 100% of the fetuses, while the extended fetal heart examination was completed in 98%. Six fetuses with cardiac defects were diagnosed during the study: three had major heart defects (aortic atresia, tetralogy of Fallot, and persistent truncus arteriosus), all detected at the early transvaginal scan; three cardiac anomalies escaped our early diagnosis; two fetuses had a minor ventricular septal defect diagnosed only postnatally; and one had multiple cardiac rhabdomyoma diagnosed in the third trimester. Our results demonstrate that between 13 and 15 weeks' gestation transvaginal echocardiographic assessment of the fetal heart in the low-risk population is feasible. Moreover, some severe anomalies may be detected at such an early gestational age.     

胎儿心脏超声智能导航技术在获取胎儿超声心动图快速筛查切面主要诊断要素中的应用价值

目的评价胎儿心脏超声智能导航技术（5D Heart）在胎儿超声心动图五个快速筛查切面诊断要素中的应用价值。 方法选取2016年10月至12月在浙江大学医学院附属邵逸夫医院超声科接受胎儿超声心动图检查的中晚孕期单胎胎儿220例,使用容积探头对220例中晚孕期单胎胎儿采集以四腔心切面为初始切面的三维容积数据共384个,采用5D Heart后处理成像,获取5个快速筛查切面,对5个切面21个要素化内容进行评分,采用χ²检验比较5D Heart与传统技术在5个诊断切面的要素显示是否存在差异,采用Pearson相关分析对5D Heart技术与传统二维超声心动图在正常胎心及异常胎心组中要素显示率作相关性分析。应用秩和检验分别对同一观察者不同时间评分结果,2个经验相对不足的医师评分结果及其分别与经验丰富的医师的评分结果进行比较。 结果220例胎儿共获取384个容积数据,其中200例胎儿的317个心脏容积数据能够用于分析,获取成功率为82.6%。5D Heart技术与传统技术在胎儿心动图快速筛查5个切面要素的显示量,差异无统计学意义（χ²=5.17,P=0.27）;正常胎心组与异常胎心组比较,切面要素显示率分别为89.6%、85.2%（r=0.94,P=0.02）。同一观察者不同时间评分结果比较、两个经验相对不足的医师比较以及分别与经验丰富的医师比较,评分结果差异无统计学意义（均P>0.05）。 结论胎儿心脏超声智能导航技术在获取胎儿快速筛查切面及显示胎儿超声心动图要素化诊断信息方面具有较高的可靠性及重复性,减少操作者技术经验的依赖性,在CHD胎儿图像规范化采集与分析、科研教学、远程会诊及基层医院筛查中具有重要的应用前景。     

Real-time 3-dimensional fetal echocardiography with an instantaneous volume-rendered display: early description and pictorial essay.

OBJECTIVE: Random fetal motion, rapid fetal heart rates, and cumbersome processing algorithms have limited reconstructive approaches to 3-dimensional fetal cardiac imaging. Given the recent development of real-time, instantaneous volume-rendered sonographic displays of volume data, we sought to apply this technology to fetal cardiac imaging. METHODS: We obtained 1 to 6 volume data sets on each of 30 fetal hearts referred for formal fetal echocardiography. Each volume data set was acquired over 2 to 8 seconds and stored on the system's hard drive. Rendered images were subsequently processed to optimize translucency, smoothing, and orientation and cropped to reveal "surgeon's eye views" of clinically relevant anatomic structures. Qualitative comparison was made with conventional fetal echocardiography for each subject. RESULTS: Volume-rendered displays identified all major abnormalities but failed to identify small ventricular septal defects in 2 patients. Important planes and views not visualized during the actual scans were generated with minimal processing of rendered image displays. Volume-rendered displays tended to have slightly inferior image quality compared with conventional 2-dimensional images. CONCLUSIONS: Real-time 3-dimensional echocardiography with instantaneous volume-rendered displays of the fetal heart represents a new approach to fetal cardiac imaging with tremendous clinical potential.     

Prenatal echocardiographic differential diagnosis of fetal cardiac tumors.

OBJECTIVES: To present data on echocardiographic findings of fetal cardiac tumors and discuss their differential diagnoses. METHODS: We retrospectively reviewed 14 cases of fetal echogenic cardiac mass diagnosed between 1990 and 2003; 12 were confirmed to be cardiac tumors and two were false-positive diagnoses. The echocardiographic characteristics examined included number, size, location and associated complications. RESULTS: Eight fetuses had a single tumor and four fetuses had multiple tumors. The left ventricle was most often affected. Parents of eight fetuses opted for termination of pregnancy, one fetus died in utero and three affected fetuses survived. Histopathological examination revealed cardiac rhabdomyoma in six fetuses, fibroma in two, teratoma in two, lipoma in one and hemangioma in one. The pitfalls associated with prenatal echocardiographic diagnosis of cardiac tumors include: they may be too small to be visualized, intracardiac echogenic foci may mimic tumors, and echogenicity resulting from extracardiac structures or neoplasms near the heart may falsely appear as tumors. CONCLUSION: Fetal cardiac tumors can be detected by echocardiography. However, differential diagnosis is important as this will affect prognosis and subsequent management.     

Three-dimensional (3D) and 4D color Doppler fetal echocardiography using spatio-temporal image correlation (STIC).

OBJECTIVE: Color Doppler echocardiography is used to visualize three transverse planes: the four-chamber, five-chamber, and three vessels and trachea views. Color Doppler spatio-temporal image correlation (STIC) is a new three-dimensional (3D) technique allowing the acquisition of a volume of data from the fetal heart that is displayed as a cineloop of a single cardiac cycle. The aim of the study was to examine the potential of color Doppler STIC to evaluate normal and abnormal fetal hearts. METHODS: This prospective study included 35 normal fetuses and 27 fetuses with congenital heart defects (CHD) examined between 18 and 35 weeks of gestation. Volume acquisition was achieved by initiating the image capture sequence from the transverse four-chamber view. Volumes were stored for later offline evaluation using a personal computer-based workstation in a multiplanar mode and as spatial volume rendering. RESULTS: Successful acquisition was possible in all 62 cases. The three planes could be demonstrated in 31/35 healthy fetuses and in 24/27 fetuses with CHD. Spatial volume rendering was attempted in 18 fetuses with CHD. In the four normal fetuses with inadequate visualization using color Doppler STIC, the region of interest was perpendicular to the ultrasound beam. In two fetuses with CHD inadequate visualization was related to an enlarged heart in late gestation, in which the entire cardiac volume could not be acquired. The third case was an 18-week fetus with complex CHD and transposed great vessels in which artifacts were related to confluent color signals as a result of low resolution in the reconstructed plane. CONCLUSIONS: STIC in combination with color Doppler ultrasound is a promising new tool for multiplanar and 3D/4D rendering of the fetal heart. Limitations may be found later in gestation in fetuses with large hearts and early in gestation as a result of low discrimination of signals. In addition, insonation perpendicular to the structure of interest does not image color Doppler signals and should be avoided during acquisition.     

Four-dimensional ultrasonography of the fetal heart using color Doppler spatiotemporal image correlation.

OBJECTIVE: To describe clinical and research applications of 4-dimensional imaging of the fetal heart using color Doppler spatiotemporal image correlation. METHODS: Forty-four volume data sets were acquired by color Doppler spatiotemporal image correlation. Seven subjects were examined: 4 fetuses without abnormalities, 1 fetus with ventriculomegaly and a hypoplastic cerebellum but normal cardiac anatomy, and 2 fetuses with cardiac anomalies detected by fetal echocardiography (1 case of a ventricular septal defect associated with trisomy 21 and 1 case of a double-inlet right ventricle with a 46,XX karyotype). The median gestational age at the time of examination was 21 3/7 weeks (range, 19 5/7-34 0/7 weeks). Volume data sets were reviewed offline by multiplanar display and volume-rendering methods. Representative images and online video clips illustrating the diagnostic potential of this technology are presented. RESULTS: Color Doppler spatiotemporal image correlation allowed multiplanar visualization of ventricular septal defects, multiplanar display and volume rendering of tricuspid regurgitation, volume rendering of the outflow tracts by color and power Doppler ultrasonography (both in a normal case and in a case of a double-inlet right ventricle with a double-outlet right ventricle), and visualization of venous streams at the level of the foramen ovale. CONCLUSIONS: Color Doppler spatiotemporal image correlation has the potential to simplify visualization of the outflow tracts and improve the evaluation of the location and extent of ventricular septal defects. Other applications include 3-dimensional evaluation of regurgitation jets and venous streams at the level of the foramen ovale.     

Tissue Doppler gated (TDOG) dynamic three-dimensional ultrasound imaging of the fetal heart.

Dynamic three-dimensional (3D) ultrasound imaging of the fetal heart is difficult due to the absence of an electrocardiogram (ECG) signal for synchronization between loops. In this study we introduce tissue Doppler gating (TDOG), a technique in which tissue Doppler data are used to calculate a gating signal. We have applied this cardiac gating method to dynamic 3D reconstructions of the heart of eight fetuses aged 20-24 weeks.The gating signal was derived from the amplitude and frequency contents of the tissue Doppler signal. We used this signal as a replacement for ECG in a 3D-volume reconstruction and visualization, utilizing techniques established in ECG-gated 3D echocardiography.The reliability of the TDOG signal for fetal cardiac cycle detection was experimentally investigated. Simultaneous recordings of tissue Doppler of the heart and continuous wave (CW) spectral Doppler of the umbilical artery (UA) were performed using two independent ultrasound systems, and the TDOG signal from one system was compared to the Doppler spectrum data from the other system. Each recording consisted of a two-dimensional (2D) sector scan, transabdominally and slowly tilted by the operator, covering the fetal heart over approximately 40 cardiac cycles. The total angle of the sweep was estimated by recording a separate loop through the center of the heart, in the elevation direction of the sweep.3D reconstruction and visualization were performed with the EchoPAC-3D software (GE Medical Systems). The 3D data were visualized by showing simultaneous cineloops of three 2D slices, as well as by volume projections running in cineloop.Synchronization of B-mode cineloops with the TDOG signal proved to be sufficiently accurate for reconstruction of high-quality dynamic 3D data. We show one example of a B-mode recording with a frame rate of 96 frames/s over 20 seconds. The reconstruction consists of 31 volumes, each with 49 tilted frames. With the fetal heart positioned 5-8 cm from the transducer, the sampling distances were approximately 0.15 mm in the beam direction, 0.33 degrees approximately 0.37 mm azimuth and 0.45 degrees approximately 0.51 mm elevation. From this single dataset we were able to generate a complete set of classical 2D views (such as four-chamber, three-vessel and short-axis views as well as those of the ascending aorta, aortic and ductal arches and inferior and superior venae cavae) with high image quality adequate for clinical use.     

Three- and four-dimensional freehand fetal echocardiography: a feasibility study using a hand-held Doppler probe for cardiac gating.

OBJECTIVE: To evaluate the clinical feasibility of the signal from a hand-held Doppler probe as a real-time tracking signal for dynamic three-dimensional (3D) (so-called four-dimensional (4D)) fetal echocardiography in a random patient cohort. METHODS: Seventy fetuses, with and without congenital heart disease, at various gestational ages (mean, 25 weeks; range, 18-38 weeks) were investigated using freehand 3D echocardiography. Time gating was achieved concurrently by obtaining a Doppler signal of the fetal heart without further signal averaging. In 10 fetuses, Doppler gating was compared to cardiotocogram (CTG)-gated 3D echo using signal averaging. Gray-scale and color Doppler dynamic 3D displays and multiplanar views were assessed according to their ability to accurately depict cardiac gating and cardiac morphology. RESULTS: In 68/70 fetuses, valid Doppler-based trigger signals were obtained. Correct cardiac gating was achieved in 231/275 (84%) 4D datasets. Doppler tracing of the fetal heart allowed beat-to-beat triggering without the necessity for signal averaging. Doppler gating detected rapid changes in the fetal heart rate more reliably than CTG gating, but was more sensitive to acoustic interference between the gating and echo-transducer when color-coded Doppler imaging was used. Image quality was highly dependent on random motion and the acoustic window. A total of 171/231 (74%) correctly gated datasets successfully demonstrated clinically useful 4D images of the fetal heart. The reconstruction of 3D and multiplanar views provided additional views not obtainable by two-dimensional imaging. CONCLUSION: These results show that a hand-held Doppler probe can be used as a reliable online gating source for 4D fetal echocardiography. Copyright 2005 ISUOG     

11~14周正常胎儿心脏超声检查

目的对妊娠11^＋0～14^＋6周正常胎儿心脏结构进行观察，获得该孕周内正常胎儿心脏的生理参数。方法对100位孕妇在妊娠11^＋0～14^＋6周进行常规经腹超声检查，同时观察胎儿心脏各切面结构并进行测量。结果胎儿心脏各切面显示率不同，四腔心显示率最高，其次是动脉交叉，而动脉导管的显示率最低。妊娠13周以后胎儿心脏结构超声可清晰显示。胎儿心脏周长、面积及各心室内径的增加与孕周有相关性，而心脏周长与胸廓周长比值，心脏面积与胸廓面积比值，左右心房比值以及房室率均相对衡定，与孕周之间无明显相关性。结论由于在妊娠13周以后胎儿心脏结构能够清晰显示，因此，可以将胎儿超声心动图检查时间提前至妊娠中期的早期。主要筛查与四腔心切面相关的严重的胎儿先天性心脏畸形，有利于胎儿严重先天性心脏畸形的早期诊断。     

Novel application of 4D sonography with B-flow imaging and spatio-temporal image correlation (STIC) in the assessment of the anatomy of pulmonary arteries in fetuses with pulmonary atresia and ventricular septal defect.

OBJECTIVES: To assess the reliability of two-dimensional gray-scale (2D) and color Doppler echocardiography in the study of the size and anatomy of the central pulmonary arteries and of the sources of pulmonary blood flow in a case series of fetuses with pulmonary atresia and ventricular septal defect (PA-VSD), and to evaluate whether the use of 4D ultrasound with B-flow imaging and spatio-temporal image correlation (STIC) can improve prenatal diagnostic accuracy. METHODS: The study population comprised a group of seven PA-VSD fetuses that had been examined by 2D and color Doppler echocardiography exclusively, and a group of five additional cases identified initially by conventional echocardiography and examined further by 4D ultrasound, for all of which a thorough postnatal or autopsy study of the size and anatomy of the pulmonary arteries and blood supply was available. RESULTS: 2D and color Doppler echocardiography failed to assess the anatomy of the central pulmonary arteries and the source of the pulmonary blood supply in 33% and 25% of the 12 cases, respectively. 4D ultrasound with B-flow imaging and STIC assessed successfully the anatomy of the pulmonary arteries and the source of pulmonary blood supply in all five fetuses examined. CONCLUSIONS: The prognosis of PA-VSD is influenced by the anatomy of the pulmonary arteries and the sources of the pulmonary blood supply, and by coexisting extracardiac and genetic anomalies. Our findings, although limited to a small sample size, suggest that 4D echocardiography with B-flow imaging and STIC, unlike 2D ultrasound, can provide thorough visualization of very small vessels and of the arterial blood supply to the lungs of fetuses with PA-VSD. 4D ultrasound may be used in the future to improve and help to detail the diagnosis of other fetal cardiac defects.     

Three-dimensional fetal echocardiography: gated versus nongated techniques.

The purpose of this study was to compare gated with nongated three-dimensional fetal echocardiography in terms of the ability to demonstrate fetal cardiac anatomy. We examined nine fetuses in utero using conventional two-dimensional sonographic imaging equipment, an electromagnetic position sensor, and a computer-graphics workstation. Free-hand sweeps were performed through the fetal heart and great vessels in either transverse or sagittal orientations with respect to the fetal heart. Seven transverse and five sagittal sweeps were selected for reconstruction and analysis. Cardiac gating was performed by using a temporal Fourier transform to determine the fundamental frequency of cardiac motion. Two-dimensional data from each sweep were reprojected to a series of volume data sets. Each series was then condensed to a single volume, so that each two-dimensional sweep could be compared with its respective gated and nongated volume data sets. The two-dimensional data were reviewed utilizing a display with forward and backward cineloop capability. The gated and nongated volume data sets were displayed interactively as a series of three orthogonal planes, with the ability of the observer to control the location of each image plane within the volume. The gated data were animated with variable display frame rates. Conventional two-dimensional imaging provided a fairly complete evaluation of the fetal heart when scanning included the four-chamber view with a sweep across the outflow tracts. Nongated three-dimensional fetal echocardiography allowed visualization of some structures and views not demonstrated with two-dimensional ultrasonography. Gated three-dimensional fetal echocardiography provided significantly better visualization and comprehension of cardiac anatomy than nongated three-dimensional fetal echocardiography. The superiority of gated over nongated three-dimensional fetal echocardiography appears to come from both improved image quality and the anatomic clues that derive from the ability to view cardiac motion.     

Cardiac malformations in first-trimester fetuses with increased nuchal translucency: ultrasound diagnosis and postmortem morphology.

OBJECTIVE: The aim of this study was to explore the diagnostic accuracy of first-trimester transvaginal echocardiography in fetuses with increased nuchal translucency (NT) thickness, by comparing the ultrasound diagnosis with the findings on postmortem examination or mid-gestational ultrasound and neonatal outcome. METHODS: Transvaginal echocardiography was performed in 45 fetuses with a NT > 95th centile. Karyotyping was performed in 43. In 20 of the 23 pregnancies in which termination of pregnancy was carried out, postmortem examination was performed to determine the presence and type of heart defect. Mid-gestational echocardiography was performed in ongoing pregnancies and neonatal follow-up information was obtained. Findings on first-trimester transvaginal echocardiography were compared to those of second-trimester echocardiography or the results of postmortem examination. The mean NT in the fetuses with and without heart defects was calculated. RESULTS: Of the 45 fetuses, heart malformations were suspected on first-trimester ultrasound in 10 (22%), of which eight (80%) were found to have a chromosomal abnormality. Postmortem examination showed minor additional findings in some cases and major discrepancies occurred in none. Septal defects were the most common defects in trisomic fetuses. In three fetuses with a 45 X karyotype, hypoplastic left heart syndrome was diagnosed. Heart defects were diagnosed in three euploid fetuses in which fetal demise occurred. The sensitivity and specificity for the detection of heart defects of transvaginal echocardiography were 88% and 97%, respectively. The mean NT in fetuses with a normal heart (4.3 mm) was significantly smaller than that of fetuses with heart defects (7.4 mm). CONCLUSION: Transvaginal echocardiography can be performed reliably in first-trimester fetuses with an increased NT. In this study, the proportion of chromosomally abnormal fetuses with a heart defect was not different from that found in newborns, except for cases of Turner syndrome. Fetal demise occurred in all three euploid fetuses with a heart malformation. The fetuses with a heart defect had a larger NT than did those without.     

产前超声诊断胎儿法洛四联症

目的 探讨产前超声诊断胎儿法洛四联症的临床价值。方法 回顾性分析15例经胎儿超声检查诊断为法洛四联症的超声资料与随访结果，分析总结胎儿心脏各切面异常声像图特点。结果13例胎儿经尸体解剖或产后手术证实为法洛四联症，2例胎儿产后超声和手术诊断为单纯室间隔缺损；胎儿法洛四联症的主要声像图特征是室间隔缺损、主动脉骑跨和肺动脉狭窄；主动脉根部内径增宽和肺动脉与主动脉内径比值减小亦有助于产前诊断。结论 超声心动图产前诊断胎儿法洛四联症具有重要的临床意义，但在检查时应注意多种影响因素。     

A systematic approach to the use of the multiplanar display in evaluation of abnormal vascular connections to the fetal heart using 4-dimensional ultrasonography.

OBJECTIVE: The multiplanar display is a modality that allows the simultaneous visualization of 3 orthogonal planes from volume data sets obtained with 3- and 4-dimensional ultrasonography. Simultaneous display of standard views used in fetal echocardiography and their orthogonal planes may provide novel ultrasonographic views for examination of the fetal heart and its vascular connections. This study was designed to determine the clinical utility of the multiplanar display in the examination of abnormal vascular connections to the fetal heart. METHODS: We reviewed 4-dimensional volume data sets, acquired with the spatiotemporal image correlation technique, from patients with abnormal vascular connections to the fetal heart. Multiplanar views of the fetal heart were used to simultaneously display standard planes used in fetal echocardiography and their corresponding orthogonal planes. RESULTS: This study included 4 volume data sets from fetuses with confirmed abnormal vascular connections to the heart, including: (1) an interrupted inferior vena cava with azygos or hemiazygos vein continuation; (2) a persistent left superior vena cava draining into a dilated coronary sinus; and (3) a dilated superior vena cava associated with a thoracic lymphangioma. Simultaneous visualization of orthogonal planes displaying abnormal vascular connections to the fetal heart facilitated identification of the abnormal vessels and their spatial relationships with other vascular structures. CONCLUSIONS: Multiplanar imaging can be used to assess abnormal vascular connections to the fetal heart and may provide novel ultrasonographic planes for fetal echocardiography using 3- and 4-dimensional ultrasonography.     

The role of the sagittal view of the ductal arch in identification of fetuses with conotruncal anomalies using 4-dimensional ultrasonography.

OBJECTIVE: Conotruncal anomalies represent one fifth of all congenital heart defects (CHDs) detected in the fetus. However, the spatial relationship of the great vessels is incorrectly defined in about 20% of these cases. The sagittal view of the ductal arch is considered a standard ultrasonographic view in fetal echocardiography and can be easily visualized using 4-dimensional (4D) ultrasonography. This study was designed to determine the role of this ultrasonographic plane for the prenatal diagnosis of conotruncal anomalies. METHODS: We reviewed 4D volume data sets, acquired with the spatiotemporal image correlation technique, from fetuses with and without confirmed conotruncal anomalies. The visualization rate of the sagittal view of the ductal arch was compared among groups using standardized multiplanar views. RESULTS: This study included 183 volume data sets from fetuses in the following groups: (1) normal echocardiographic findings (n = 130); (2) conotruncal anomalies (n = 18); and (3) other CHDs (n = 35). Volumes of poor image quality were excluded from analysis (8.2% [15/183]). The visualization rate of the sagittal view of the ductal arch was significantly lower in fetuses with conotruncal anomalies (5.6% [1/18]) than that in fetuses without abnormalities (93.1% [108/116]) and that in fetuses with other CHDs (79.4% [27/34]; P < .01). Absence of visualization of the sagittal view of the ductal arch was associated with a likelihood ratio of 9.44 (95% confidence interval, 5.8-15.5) to have conotruncal anomalies. CONCLUSIONS: The sagittal view of the ductal arch may play an important role in the screening and prenatal diagnosis of conotruncal anomalies in 4D ultrasonography.