Step-by-step recommendations utilizing four-dimensional intracardiac echocardiography in left atrial appendage procedures.

INTRODUCTION: Four-dimensional (4D) intracardiac echocardiography (ICE) is a novel cardiac imaging modality that has been applied to various workflows, including catheter ablation, tricuspid valve repair, and left atrial appendage occlusion (LAAO). The use of this type of advanced ICE imaging may ultimately allow for the replacement of transesophageal echocardiography (TEE) for LAAO, providing comparable imaging quality while eliminating the need for general anesthesia. METHODS: Based on our initial clinical experience with 4D ICE in LAAO, we have developed an optimized workflow for the use of the NUVISION™ 4D ICE Catheter in conjunction with the GE E95 and S70N Ultrasound Systems in LAAO. In this manuscript, we provide a step-by-step guide to using 4D ICE in conjunction with compatible imaging consoles. We have also evaluated the performance of 4D ICE with the NUVISION Ultrasound Catheter versus TEE in one LAAO case and present those results here. RESULTS: In our comparison of 4D ICE using our optimized workflow with TEE in an LAAO case, ICE LAA measurements were similar to those from TEE. The best image resolution was seen via ICE in 2-dimensional and multislice modes (triplane and biplane). The FlexiSlice multiplanar reconstruction tool, which creates an en-face image derived from a 4D volume set, also provided valuable information but yielded slightly lower image quality, as expected for these volume-derived images. For this case, comparable images were obtained with TEE and ICE but with less need to reposition the ICE catheter. CONCLUSION: The use of optimized 4D ICE catheter workflow recommendations allows for efficient LAAO procedures, with higher resolution imaging, comparable to TEE.

Four-Dimensional Ultrasound Imaging of Spatial Relationship of Great Arteries in Fetuses With Transposition of Great Arteries.

The great artery relationship in transposition of great arteries (TGA) is based on the degree of resorption and growth of subsemilunar conus. In transposition of great arteries, the spatial relationship of the great arteries can be variable. Commonly, the aorta will be related right and anterior to pulmonary artery (D-TGA). Less commonly, the aorta can be related left and anterior (SDL-TGA), side-by-side, and antero-posterior to pulmonary artery. Four fetuses with concordant atrioventricular and discordant ventriculoarterial connection with various great arteries relationship were presented in this imaging essay.

Dynamic assessment of the tricuspid annulus in a healthy Asian population: A four-dimensional echocardiography study.

BACKGROUND: Tricuspid annulus (TA) geometry and function reference values are limited, especially for Asian populations. We aimed to explore TA using four-dimensional echocardiography (4DE) in a healthy Asian population. METHODS: A total of 355 healthy Asian volunteers (median age 34 years; 52% males) were prospectively enrolled. TA geometry and function were analyzed using 4DE throughout the cardiac cycle. RESULTS: The TA area, perimeter, and dimensions were smallest at end systole (ES) and largest at late diastole (LD). Normal TA parameters at end diastole (ED) in different sex and age groups were obtained. TA areas, perimeters, and dimensions in males were significantly larger than those in females at ED; BSA-indexed perimeters and BSA-indexed dimensions in males were significantly smaller than those in females at ED. TA parameters correlated well with tricuspid valve (TV) tenting, right ventricle (RV), and right atrium (RA) parameters. CONCLUSIONS: Reference values of TA parameters were obtained by 4DE in an Asian population. Quantitative data on TA geometry and function are essential for TA pathology and therapeutics.

Unveiling cardiac insights: Exploring early left ventricular dysfunction in polycythemia vera through 4D-STE and fragmented QRS analysis.

BACKGROUND: Polycythemia vera (PV), characterized by elevated red blood cell counts, poses challenges to cardiovascular health with potential impacts on cardiac function. Myocardial infarction (MI) and heart failure are major causes of mortality in PV patients. Early detection of left ventricular systolic dysfunction is crucial for optimizing outcomes. METHODS: Fifty-two PV patients and 45 healthy controls were recruited. Four-dimensional speckle tracking echocardiography (4D-STE) and fragmented QRS complexes (fQRS) on electrocardiograms were utilized to assess cardiac mechanics. Hematological and echocardiographic parameters were measured, and statistical analyses were performed. RESULTS: PV patients exhibited significantly higher hematocrit and red cell distribution width compared to controls. Global longitudinal strain (GLS), global circumferential strain (GCS), global radial strain (GRS), and global area strain (GAS) were lower in PV patients. fQRS complexes were associated with longer disease duration and reduced GCS and GAS values. Hematocrit correlated positively with LV-GCS and LV-GAS. Multiple linear regression revealed that disease duration and fQRS presence independently predicted LV-GAS. CONCLUSION: This study underscores the intricate link between elevated red blood cell counts, disease duration, and cardiac function in PV patients. Combining 4D-STE and fQRS complexes enhances the identification of early left ventricular systolic dysfunction. These findings offer potential improvements in recognizing and managing cardiovascular complications in PV patients, with implications for future research and clinical practice. Further investigations are needed to elucidate underlying mechanisms and validate these markers in larger cohorts.

Prenatal diagnosis of ductal origin of distal pulmonary artery: presentation of three cases and literature review.

Ductal origin of distal pulmonary artery (DODPA) is a rare congenital cardiovascular anomaly, with an incidence of approximately 1 in 200 000 people. It involves the proximal interruption of one pulmonary artery branch, with the distal part arising from the base of the brachiocephalic artery, via the ipsilateral ductus arteriosus (DA) and the intrapulmonary branch of the pulmonary artery is usually intact. If timely treatment is not provided after birth, it is very likely that, due to DA closure, severe hypoplasia will occur in the lung supplied by the abnormal pulmonary artery. Hence, prenatal diagnosis of DODPA is important to enable initiation of prostaglandin treatment and early rehabilitation of the affected lung. Herein, we report three cases of fetal DODPA diagnosed via two-dimensional (2D) ultrasonography combined with four-dimensional (4D) spatiotemporal image correlation. We also present a literature review, and explore the ultrasonographic findings and the importance of 2D and 4D ultrasonography in obtaining an accurate prenatal diagnosis of DODPA. © 2021 International Society of Ultrasound in Obstetrics and Gynecology.

Four-dimensional quantification on left atrial volume-strain in coronary heart disease patients without regional wall motion abnormalities: Correlation with the severity of coronary stenosis.

OBJECTIVE: Echocardiography is a time and cost-effective imaging modality, providing evidence of myocardial ischemia by detecting the regional wall motion abnormalities (RWMA). However, quite a few coronary heart disease (CHD) patients do not present RWMA. The left atrium (LA) plays an irreplaceable role in determining the prognosis and risk stratification of cardiovascular disease including CHD. In this present study, we intend to explore the myocardial mechanics changes of LA mainly using four-dimensional (4D) LA quantitative volume-strain in CHD patients without RWMA at rest but were confirmed by coronary angiography (CAG) and to figure out several variables of the LA that could contribute to the identification of those patients. METHODS: We prospectively enrolled 76 patients who underwent two-dimensional echocardiography (2DE), four-dimensional echocardiography (4DE), and CAG for suspected CHD but without echocardiographic visible RWMA at rest. Patients diagnosed with CHD by CAG were furtherly divided into three groups according to the extent of coronary stenosis accessed by Gensini score (GS) as the mild, moderate, and severe CHD group. Twenty-four subjects with negative CAG results served as the control group. LA end-systolic anteroposterior diameter (LAAPD) and biplane LV ejection fraction (Biplane LVEF) were measured by 2DE; LA maximum volume (LAVmax), LA minimum volume (LAVmin), LA volume at the onset of atrial contraction (LAVpreA), LAVmax index (LAVmaxI), LA ejection volume (LAEV), LA ejection fraction (LAEF) accompanied by LA longitudinal strain during reservoir phase (LASr), conduit phase (LAScd), contraction phase (LASct) and LA circumferential strain during reservoir phase (LASr_c), conduit phase (LAScd_c), contraction phase (LASct_c) were measured by 4DE automatically. We compared these parameters between groups, explored how they change and whether they are related to the CHD severity. RESULTS: LAEF, LASr_c, and LASct_c was lower in CHD group compared with the control group (p = .031, .002, .004, respectively). Pearson correlation analysis showed that LASr, LASct, LASr_c, and LASct_c negatively correlated with the GS. Additionally, LASr of patients in the severe CHD group decreased significantly compared with those in the mild CHD group, moderate CHD group, and control group, demonstrating the highest area under the receiver operating characteristic (ROC) curve (AUC) (AUC = .736 [p = .003, 95% CI .589-.884], sensitivity 67.8%, specificity 70.6%) with the cut-off value of 17.5% for predicting severe CHD patients. CONCLUSION: Four-dimensional LA strain may provide new insight into identification and management for CHD patients and correlate with CHD severity. LASr showed good sensitivity (67.8%) and specificity (70.6%) for diagnosing severe CHD individuals.

Prenatal diagnosis of type A fetal interrupted aortic arch by four-dimensional echocardiography with HD-flow STIC: A case report.

Interrupted aortic arch (IAA) is a rare complex congenital heart disease characterized by interrupted continuity between ascending aorta and descending aorta. Prenatal diagnosis of IAA by echocardiography is not uncommonly reported despite its rarity. However, employing four-dimensional ultrasound HD-flow imaging and spatiotemporal image correlation (STIC) in diagnosis of this condition has seldom been reported. We report a case of fetal IAA prenatally diagnosed by two-dimensional echocardiography and HD-flow STIC.

First Trimester Prenatal Diagnosis of a Conotruncal Anomaly Using Spatiotemporal Image Correlation Imaging Confirmed by Conventional Autopsy.

BackgroundFetal echocardiography continues to be the first line investigation for detecting congenital heart diseases (CHD). As accurate and complete diagnosis of complex heart disease is often difficult in the first trimester due to small size of the fetal heart, confirmation/expanded description by fetopsy provides the best information for accurate counseling for future pregnancies. Although non invasive fetal autopsy alternatives have been investigated with favorable results, conventional autopsy remains the gold standard procedure used to confirm the fetal abnormalities. Case report: We describe a conotruncal anomaly diagnosed at 12 weeks gestation using spatiotemporal image. The fetopsy confirmed the diagnosis of Type I Truncus arteriosus. Conclusion: Four-dimensional STIC imaging provides incremental benefits in evaluation of fetal cardiac anomalies, and confirmation by autopsy findings allows further refinement of the diagnosis.

Improving characterization of hypertrophy-induced murine cardiac dysfunction using four-dimensional ultrasound-derived strain mapping.

Mouse models of cardiac disease have become essential tools in the study of pathological mechanisms, but the small size of rodents makes it challenging to quantify heart function with noninvasive imaging. Building off recent developments in high-frequency four-dimensional ultrasound (4DUS) imaging, we have applied this technology to study cardiac dysfunction progression in a murine model of metabolic cardiomyopathy. Cardiac knockout of carnitine palmitoyltransferase 2 (Cpt2M-/-) in mice hinders cardiomyocyte bioenergetic metabolism of long-chain fatty acids, and leads to progressive cardiac hypertrophy and heart failure. The proposed analysis provides a standardized approach to measure localized wall kinematics and simultaneously extracts metrics of global cardiac function, LV morphometry, regional circumferential strain, and regional longitudinal strain from an interpolated 4-D mesh of the endo- and epicardial boundaries. Comparison of metric changes due to aging suggests that circumferential strain at the base and longitudinal strain along the posterior wall are most sensitive to disease progression. We further introduce a novel hybrid strain index (HSI) that incorporates information from these two regions and may have greater utility to characterize disease progression relative to other extracted metrics. Potential applications to additional disease models are discussed that could further demonstrate the utility of metrics derived from 4DUS imaging and strain mapping.NEW & NOTEWORTHY High-frequency four-dimensional ultrasound can be used in conjunction with standardized analysis procedures to simultaneously extract left-ventricular global function, morphometry, and regional strain metrics. Furthermore, a novel hybrid strain index (HSI) formula demonstrates greater performance compared with all other metrics in characterizing disease progression in a model of metabolic cardiomyopathy.

3D/4D spatiotemporal image correlation (STIC) fetal echocardiography provides incremental benefit over 2D fetal echocardiography in predicting postnatal surgical approach in double-outlet right ventricle.

OBJECTIVE: To analyze the incremental benefit of 3D/4D spatiotemporal image correlation (STIC) fetal echocardiography over 2D fetal echocardiography with respect to the accuracy of identification of anatomic details crucial for surgical decision-making and in predicting surgical approach in fetuses with double-outlet right ventricle (DORV). METHODS: This was a retrospective study of fetuses with DORV which had undergone both 2D echocardiography and 3D/4D STIC echocardiography and which underwent surgery postnatally in a tertiary pediatric cardiac center in Kerala between October 2015 and March 2019. All such cases with normal atrial arrangement, concordant atrioventricular connections and balanced ventricles were included. 2D and 3D/4D STIC fetal echocardiographic data were analyzed by two experienced observers blinded to the other dataset. Anatomic variables crucial for surgical decision-making, i.e. location and routability of the ventricular septal defect, relationship of the great arteries and presence of outflow obstruction, were compared between the two modalities with respect to agreement with postnatal echocardiography. The accuracy of prenatal prediction of the surgical pathway was compared between 2D and 3D/4D modalities with respect to the procedure undertaken. RESULTS: Included in the study were 22 fetuses with DORV which had undergone both 2D and 3D/4D imaging as well as postnatal surgery. Accuracy of prenatal interpretation of all four anatomic variables was significantly higher using 3D/4D STIC than using 2D fetal echocardiography (19/22 (86.4%) vs 8/22 (36.4%), P < 0.001). Surgical procedures included single-stage repair in 14 (63.5%) patients and a multistage approach in eight (36.4%). Prenatal prediction of the surgical pathway was significantly more accurate on 3D/4D STIC than on 2D echocardiography (20/22 (90.9%) vs 12/22 (54.5%), P = 0.021). Prenatal predictive accuracy of single-stage biventricular repair was significantly better for 3D/4D STIC than for 2D echocardiography (14/14 (100%) vs 8/14 (57.1%), P = 0.04). CONCLUSION: Addition of 3D/4D STIC to conventional 2D fetal echocardiography confers incremental benefit on the accuracy of identification of anatomic details crucial for surgical decision-making and the prediction of postnatal surgical approach in fetuses with DORV, thereby potentially aiding prenatal counseling. © 2020 International Society of Ultrasound in Obstetrics and Gynecology.

Prenatal evaluation of fetal atrioventricular valves by real-time 4D volume imaging with electronic matrix probe.

BACKGROUND: The purpose of this study is to evaluate the feasibility using real-time four-dimensional (RT 4D) volume imaging with electronic matrix probe to observe the morphology of atrioventricular valves in normal and abnormal fetuses, measure the area and circumference of atrioventricular valves in normal fetuses and analyze the correlation with gestational age. METHODS: RT 4D volume imaging with electronic matrix probe was used to collect cardiac volume data of 162 normal fetuses with the gestational age from 22 to 32 weeks and 19 fetuses with atrioventricular valves abnormalities were also enrolled. All the volume data were analyzed and processed in real-time. The morphology of mitral and tricuspid valves was observed in surface mode. The area and circumference of valves were measured in a 4D render view at the end of diastole and analyzed the correlation with gestational age. RESULTS: In 148 of 162 fetuses (91%), the 4D rendered image could be successfully obtained, which clearly showed the morphology of the atrioventricular valves. The area and circumference of mitral and tricuspid valves were positively correlated with gestational age (P < 0.01). Furthermore, 4D rendered images were successfully obtained in 17 of 19 fetuses (89%) with atrioventricular valves abnormalities. CONCLUSIONS: The reference range of the area and circumference of atrioventricular valves in normal fetuses at different gestational weeks could be determined by using the RT 4D volume imaging with electronic matrix probe, which can provide certain diagnostic information for the clinic. The RT 4D images could display the valves morphology vividly in both normal and abnormal fetuses, including some subtle lesions which are not identified by traditional two-dimensional (2D) echocardiography. It is feasible to use the RT 4D volume imaging with electronic matrix probe to perform the prenatal evaluation in the fetal atrioventricular valves.

A 'holistic' sonographic view on congenital heart disease - How automatic reconstruction using fetal intelligent navigation echocardiography (FINE) eases the unveiling of abnormal cardiac anatomy part I: Right heart anomalies.

Attempting a comprehensive examination of the fetal heart remains challenging for unexperienced operators as it emphasizes the acquisition and documentation of sequential cross-sectional and sagittal views and inevitably results in diminished detection rates of fetuses affected by congenital heart disease. The introduction of four-dimensional spatio-temporal image correlation (4D STIC) technology facilitated a volumetric approach for thorough cardiac anatomic evaluation by the acquisition of cardiac 4D datasets. By analyzing and re-arranging of numerous frames according to their temporal event within the heart cycle, STIC allows visualization of cardiac structures as an endless cine loop sequence of a complete single cardiac cycle in motion. However, post-analysis with manipulation and repeated slicing of the volume usually requires experience and in-depth anatomic knowledge, which limits the widespread application of this advanced technique in clinical care and unfortunately leads to the underestimation of its diagnostic value to date. Fetal intelligent navigation echocardiography (FINE), a novel method that automatically generates and displays nine standard fetal echocardiographic views in normal hearts, has shown to be able to overcome these limitations. Very recent data on the detection of congenital heart defects (CHDs) using the FINE method revealed a high sensitivity and specificity of 98% and 93%, respectively. In this two-part manuscript, we focused on the performance of FINE in delineating abnormal anatomy of typical right and left heart lesions and thereby emphasized the educational potential of this technology for more than just teaching purposes. We further discussed recent findings in a pathophysiological and/or functional context.

A "holistic" sonographic view on congenital heart disease: How automatic reconstruction using fetal intelligent navigation echocardiography eases unveiling of abnormal cardiac anatomy part II-Left heart anomalies.

Volume ultrasound has been shown to provide valid complementary information on fetal anatomy. Four-dimensional assessment (4D) of the fetal cardiovascular system using spatial-temporal image correlation (STIC) allows for detailed examination of a highly complex organ from the early second trimester onward. There is compelling evidence that this technique harbors quite a number of diagnostic opportunities, but manual navigation through STIC volume datasets is highly operator dependent. In fact, STIC is not incorporated yet into daily practice. Application of the novel fetal intelligent navigation echocardiography (FINE) considerably simplifies fetal cardiac volumetric examinations. This automatic technique applied on cardiac volume datasets reportedly has both high sensitivity and specificity for the detection of congenital heart defects (CHDs). Part I reviewed current data regarding detection rates of CHDs and illustrated the additional value of an automatic approach in delineating cardiac anatomy exemplified by congenital lesions of the right heart. In part II of this pictorial essay, we focused on left heart anomalies and aimed to tabulate recent findings on the quantification of normal and abnormal cardiac anatomy.

Reliability of Sonography-based Volume Computer Aided Diagnosis in the Normal Fetal Heart.

OBJECTIVES: To explore the inter- and intra-observer reliability of Sonography-based Volume Computer Aided Diagnosis (SonoVCAD) in the display of 8 diagnostic planes of fetal echocardiography and to evaluate its efficiency. METHODS: Three-dimensional volume data sets of the 56 normal singleton fetuses were acquired from a 4-chamber view by using a volume probe. After processing the data sets by using SonoVCAD, 8 cardiac diagnostic planes were displayed automatically. Three doctors with different experiences of performing fetal echocardiography evaluated each diagnostic plane and the success rates of 8 diagnostic planes were calculated. Inter-observer and intra-observer reliabilities were estimated by Cohen's kappa statistics. RESULTS: A total of 276 volume data sets acquired from the 56 normal fetuses were used for SonoVCAD analysis and display. The success rate of each diagnostic section was more than 90%, ranging from 90.6% to 99.6%. Among 276 volumes, 81.5% (225/276) of volumes were able to generate all 8 diagnostic views successfully. Moderate to substantial agreement (kappa, 0.509-0.794) was found between 2 less experienced operators. Moderate to near-perfect agreement (kappa, 0.439-0.933) was found between an expert and 2 less experienced sonographers. Intra-observer reliability was substantial to near-perfect (kappa, 0.602-0.903). The efficiency of SonoVCAD was assessed. The expert spent less time than 2 less experienced examiners (P < 0.001) but no significant difference was found between 2 less experienced examiners (P = 0.176). Besides, SonoVCAD consumed significantly less time than 2-dimensional ultrasound (P < 0.001). CONCLUSIONS: SonoVCAD can significantly improve the success rates of 8 diagnostic planes in fetal echocardiography with low operator dependency, good reproducibility and high efficiency.

Three-Dimensional Printed Model Fabrication and Effectiveness Evaluation in Fetuses With Congenital Heart Disease or With a Normal Heart.

OBJECTIVES: The purpose of this study was to investigate the technical feasibility and accuracy of applying 3-dimensional (3D) printing of normal and abnormal fetal hearts based on spatiotemporal image correlation (STIC) volume-rendered data. METHODS: Spatiotemporal image correlation volume images of 15 healthy fetuses and 15 fetuses with cardiac abnormalities were collected, and Mimics software (Materialise NV, Leuven, Belgium) was used to postprocess the volume data to obtain a 3D digital model of fetal heart and large blood vessel morphologic characteristics and to output the file to a 3D printer for printing the 3D model of the fetal heart and large blood vessels. The effect accuracy of the 3D printed model was qualitatively evaluated by showing the 3D anatomic structure of the model combined with echocardiographic or autopsy results, and the dimensional accuracy of the 3D printed model was quantitatively evaluated by comparing the measured data of the model and echocardiography. RESULTS: In all 30 fetuses, STIC volume data of the fetal heart were successfully reprocessed and printed out, which could visually display the morphologic characteristics of the fetal heart chamber and passage of the great vessels under normal and abnormal pathologic conditions. No significant differences in all of the heart size parameters were found between the 3D digital model, 3D printed model, and routine echocardiographic images (all P > .05). Moreover, the size parameters were concordant well between the methods, and all of the data points fell within the limits of agreement. CONCLUSIONS: It is feasible to 3D print the fetal heart using STIC volumetric images as the data source, and the 3D printed model can fully and accurately display abnormal anatomic structures of the heart.

Four-Dimensional Volume-Strain Expression in Asymptomatic Primary Hypertension Patients Presenting with Subclinical Left Atrium-Ventricle Dysfunction.

OBJECTIVE: The purpose of this study was to evaluate the different components of left atrial (LA) dysfunction predictors in asymptomatic primary systemic hypertension patients with preserved left ventricular (LV) ejection fraction, particularly using LA 4-dimensional (4D) longitudinal and circumferential strain values. METHODS AND RESULTS: Patients with no left ventricular hypertrophy (NLVH) and left ventricular hypertrophy (LVH) are all asymptomatic regarding primary blood hypertension. Thirty NLVH patients and 30 LVH patients according to LV mass index and 40 controls analyzed by 4D echocardiography were prospectively enrolled. LA volumes and longitudinal and circumferential strains were measured using 4D volume-strain echocardiography with a Vivid E95 Version 203 instrument. Correlation analysis indicated a significant relation between LV 4D mass index and LA 4D longitudinal/circumferential strain (r = -0.446 to 0.381, p = 0.000-0.042). LVH patients had a reduced LA emptying fraction compared with NLVH patients and control subjects (p < 0.01). NLVH patients had an impaired LA conduit function and increased contractile function compared with the control group (p < 0.01). LVH patients had increased LA volumes and significantly decreased reservoir, conduit and contractile functions compared with the controls (p < 0.01). LVH patients had increased LA volumes and decreased reservoir and contractile functions compared with NLVH patients (p < 0.01). The clinical utility of LA 4D volume-strain measurement was verified by receiver-operating characteristic curve analysis showing larger net benefits as evaluated with NLVH, LVH and control group comparisons. Interclass correlation coefficients of interobserver and intraobserver assessments in the LV and LA 4D value evaluations were >0.75 and >0.85, respectively. CONCLUSIONS: LVH patients showed increased LA volumes and decreased LA emptying fractions. LA reservoir, conduit and contractile functions were significantly impaired in LVH patients. Decreased LA conduit function and increased contractile function were revealed in NLVH patients. LA volumetric and functional analyses with 4D volume-strain echocardiography may facilitate the recognition of subtle LA and LV dysfunctions in asymptomatic systemic hypertension patients.

Commercial 4-dimensional echocardiography for murine heart volumetric evaluation after myocardial infarction.

BACKGROUND: Traditional preclinical echocardiography (ECHO) modalities, including 1-dimensional motion-mode (M-Mode) and 2-dimensional long axis (2D-US), rely on geometric and temporal assumptions about the heart for volumetric measurements. Surgical animal models, such as the mouse coronary artery ligation (CAL) model of myocardial infarction, result in morphologic changes that do not fit these geometric assumptions. New ECHO technology, including 4-dimensional ultrasound (4D-US), improves on these traditional models. This paper aims to compare commercially available 4D-US to M-mode and 2D-US in a mouse model of CAL. METHODS: 37 mice underwent CAL surgery, of which 32 survived to a 4 week post-operative time point. ECHO was completed at baseline, 1 week, and 4 weeks after CAL. M-mode, 2D-US, and 4D-US were taken at each time point and evaluated by two separate echocardiographers. At 4 weeks, a subset (n = 12) of mice underwent cardiac magnetic resonance (CMR) imaging to serve as a reference standard. End systolic volume (ESV), end diastolic volume (EDV), and ejection fraction (EF) were compared among imaging modalities. Hearts were also collected for histologic evaluation of scar size (n = 16) and compared to ECHO-derived wall motion severity index (WMSI) and global longitudinal strain as well as gadolinium-enhanced CMR to compare scar assessment modalities. RESULTS: 4D-US provides close agreement of ESV (Bias: -2.55%, LOA: - 61.55 to 66.66) and EF (US Bias: 11.23%, LOA - 43.10 to 102.8) 4 weeks after CAL when compared to CMR, outperforming 2D-US and M-mode estimations. 4D-US has lower inter-user variability as measured by intraclass correlation (ICC) in the evaluation of EDV (0.91) and ESV (0.93) when compared to other modalities. 4D-US also allows for rapid assessment of WMSI, which correlates strongly with infarct size by histology (r = 0.77). CONCLUSION: 4D-US outperforms M-Mode and 2D-US for volumetric analysis 4 weeks after CAL and has higher inter-user reliability. 4D-US allows for rapid calculation of WMSI, which correlates well with histologic scar size.

Assessment of the quality of fetal heart standard views using the FAST, STAR, and FINE four-dimensional ultrasound techniques in the screening of congenital heart diseases.

OBJECTIVE: To compare the quality of standard fetal echocardiographic views obtained by four-dimensional ultrasound with those obtained by the simple targeted arterial rendering (STAR) technique, four-chamber view swing technique (FAST), and fetal intelligent navigation echocardiography (FINE/5D Heart® ) technique. METHODS: This was a cross-sectional prospective study that included pregnant women between 22 and 34 weeks of gestation, with normal fetuses. Fetal heart volumes were acquired using spatio-temporal image correlation (STIC) with the fetal spine between 2 and 9 o'clock. The FAST/STAR techniques consist of the manipulation of STIC volumes by drawing OmniView™ lines to obtain echocardiographic views. The FINE/5D Heart® technique uses intelligent navigation to automatically generate echocardiographic views. The quality of the images was classified as excellent, good, acceptable, and unacceptable. The analysis was performed using the Bonferroni multiple comparisons test. RESULTS: The study included 101 pregnant women aged between 16 and 44 years. There was no mean difference in image quality between the techniques regarding fetal spine position in all echocardiographic views (P > .05). However, in the five-chamber, left ventricular outflow tract, right ventricular outflow tract, ductal arch, superior vena cava/inferior vena cava, and abdomen/stomach views, there was a statistically significant mean difference quality between the techniques, regardless of the spine position (P < .05). The best mean image quality was obtained by the FINE technique (P ≤ .016 for all fetal echocardiographic views). CONCLUSION: The quality of the echocardiographic views obtained using the FINE technique was superior to that of those generated by the FAST/STAR techniques in normal fetuses.

Prenatal diagnosis of fetal aortopulmonary window by two- and four-dimensional echocardiography with spatiotemporal image correlation.

BACKGROUND: Aortopulmonary window (APW) is a rare congenital heart disease which challenges most screening sonographers. The current study aims to summarize the two-dimensional (2D) and four-dimensional (4D) sonographic features in the fetal diagnosis. METHODS: Ten cases of fetal APW were retrospectively reviewed, including 6 and 4 fetuses with distal and proximal defects, respectively. In addition, 40 normal fetuses with similar gestational age were also enrolled. The angle (α) between the pulmonary artery and aorta, and the length (D) of the ductus/pulmonary artery before its convergence with aorta were measured and compared between the normal and APW fetuses, respectively. Cardiac volumes of APW fetuses were acquired with spatial temporal image correlation (STIC) technique and post-analyzed to obtain 4D rendered images. RESULTS: The D and the α were smaller and greater in distal APW fetuses than those in the normal fetuses, respectively (both P < .01), while no difference presented between the proximal APW fetuses and the normal fetuses. The ductus was absent for all distal APW fetuses, while it was normal for proximal APW fetuses. In 9 of 10 fetuses (90%), the 4D rendered image could be successfully obtained, which clearly showed the abnormal blood communication between the two great arteries in space. CONCLUSION: It is essential to scan around the three-vessel view and three-vessel trachea view to identify fetal APW using grayscale and color Doppler echocardiography. Distal APW is always with an increasing angulation between aorta and the pulmonary artery, and without the presence of normal ductus. 4D STIC technique may provide additional spatial relationships of the great arteries and thus help the diagnosis and consultation.

Semiautomatic Fetal Intelligent Navigation Echocardiography Has the Potential to Aid Cardiac Evaluations Even in Less Experienced Hands.

OBJECTIVES: To investigate the interobserver and intraobserver variability and corresponding learning curve in a semiautomatic approach for a standardized assessment of the fetal heart (fetal intelligent navigation echocardiography [FINE]). METHODS: A total of 30 stored spatiotemporal image correlation volume data sets of second-trimester fetuses were evaluated by 3 physicians with different levels of expertise in fetal echocardiography by using the FINE approach. Data were analyzed regarding the examination time and proper reconstruction of the diagnostic cardiac planes. The completions and numbers of correct depictions of all diagnostic planes were evaluated by a blinded expert (time t0). To determine interobserver and intraobserver variability, the volumes were reassessed after a 4-week training interval (time t1). RESULTS: All operators were able to perform the investigation on all 30 volumes. At t0, the interobserver variability between the beginner and both the advanced (P = .0013) and expert (P < .0001) examiners was high. Focusing on intraobserver variability at t1, the beginner showed a marked improvement (P = .0087), whereas in advanced and expert hands, no further improvement regarding proper achievement of all diagnostic planes could be noticed (P > .999; P = .8383). The beginner also showed improvement in the mean investigation time (t0, 82.8 seconds; t1, 73.4 seconds; P = .0895); nevertheless, the advanced and expert examiners were faster in completing the examination (t1, advanced, 20.9 seconds; expert, 28.3 seconds; each P < .0001). CONCLUSIONS: Based on our results, the FINE technique is a reliable and easily learned method. The use of this semiautomatic work flow-based approach supports evaluation of the fetal heart in a standardized and time-saving manner. A semiautomatic evaluation of the fetal heart might be useful in facilitating the detection of fetal cardiac anomalies.