Evaluation of cardiac findings using speckle tracking in fetuses with hemoglobin Bart's disease.

OBJECTIVE: Hemoglobin (Hb) Bart's disease is a severe manifestation of alpha thalassemia, resulting in fetal tissue hypoxia and severe anemia. There is limited research available on assessing fetal speckle tracking analysis as a response to fetal anemia caused by Hb Bart's disease and its utility as a sonographic predictor for Hb Bart's disease. This study aimed to assess the diagnostic performance of fetal cardiac parameters derived from speckle tracking echocardiography for distinguishing between affected and unaffected fetuses in pregnancies at risk of Hb Bart's disease during the 17-24 gestational weeks. METHODS: A total of 115 pregnant women at risk for fetal Hb Bart's disease, who underwent either amniocentesis or cordocentesis at Siriraj Hospital, Bangkok Thailand, were included. Speckle tracking analysis was performed on the 4-chamber view (4CV) of the fetal heart, assessing heart size, shape, ventricular contractility, and left ventricular function prior to invasive prenatal testing. Logistic regression analysis determined significant cardiac predictors and calculated the probability of a fetus having Hb Bart's disease. RESULTS: Among the cohort, 38 fetuses (33%) were diagnosed with Hb Bart's disease, and 9 cases (7.8%) exhibited frank hydropic signs. In comparison to the control group, affected fetuses displayed a notable enlargement of the 4CV and a more globular shape specifically in the right ventricular chamber. Additionally, there were significant differences in the left global and longitudinal contractility between affected and unaffected fetuses. However, at mid-gestation, no significant distinctions were observed in terms of transverse contractility and left ventricular function between the two groups. Based on logistic regression analysis, combined cardiac parameters derived from speckle tracking analysis as a function of head circumference, could differentiate non-hydropic fetuses with Hb Bart's disease from unaffected fetuses, achieving a maximum sensitivity of 100%, specificity of 98.7%, and overall accuracy of 99.06%. CONCLUSIONS: Speckle tracking echocardiography has the potential to accurately identify early fetal heart changes in individuals at risk of developing Bart's anemia during the second trimester. This not only offers a novel predictive marker for Hb Bart's disease but also helps address the question of the underlying mechanisms of heart failure associated with anemia. This article is protected by copyright. All rights reserved.

Correction of fetal umbilical vein flow imbalance following laser surgery for twin-twin transfusion syndrome.

OBJECTIVES: Twin-twin transfusion syndrome (TTTS) is characterized by unequal hemodynamics between the twins. We aimed to assess preoperatively the difference in umbilical vein flow (UVF) between the recipient and donor monochorionic diamniotic twins and evaluate the change in UVF following laser surgery in both twins. METHODS: This was a retrospective cohort study of differences in UVF that occurred following laser surgical treatment of TTTS. Sonographic assessment of the umbilical vein before and 24 h after fetoscopic laser surgery for TTTS was performed. Umbilical vein diameter and time-averaged maximum velocity were measured, and UVF per kg (UVF/kg) was converted into a Z-score by a calculator created using gestational age as an independent variable. Z-score values were converted into centiles, which were evaluated statistically. Median differences in UVF/kg centile values were adjusted for TTTS stage and presence of arterioarterial anastomoses. RESULTS: The study population consisted of 363 TTTS patients. The adjusted preoperative median difference in UVF/kg centile between the recipient vs donor twin was 17.9% (-17.1% to 57.6%), P < 0.0001. The adjusted median difference in UVF/kg centile between the postoperative vs preoperative period among recipients was 2.2% (-10.8% to 13.8%), P < 0.0001, while the adjusted median difference among donors was 27.3% (8.2%-34.6%), P < 0.0001. CONCLUSION: The preoperative difference in UVF between the recipient and donor twins confirms the pathophysiology of TTTS. Postoperatively, the substantial increase in UVF of the donor twin and the relatively small increase in UVF of the recipient twin confirm that ablation of the vascular communications resulted in rapid improvement in perfusion of the donor twin. © 2022 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Improved detection of coarctation of the aorta using speckle-tracking analysis of fetal heart on last examination prior to delivery.

OBJECTIVE: The false-positive rate for prenatal diagnosis of coarctation of the aorta (FP-CoA) commonly exceeds 50%, with an accurate detection rate of < 50%. This study was conducted to determine if the sensitivity for prenatal detection of true CoA and the FP-CoA rate could be improved by evaluating the fetal epicardial size and shape in the four-chamber view (4CV) and the endocardial right (RV) and left (LV) ventricular size, shape and contractility. METHODS: We analyzed retrospectively Digital Imaging and Communications in Medicine (DICOM) clips of the 4CV from the last examination prior to delivery in a series of 108 fetuses with CoA suspected prenatally by pediatric cardiologists using traditional diagnostic criteria. Postnatal evaluation distinguished those fetuses which subsequently required CoA surgery (true positives; true CoA) from those that were FP-CoA. Postnatal cardiac abnormalities were identified for each group. For the prenatal evaluation, we measured the 4CV end-diastolic epicardial area, circumference, length, width and global sphericity index. Speckle-tracking analysis was used to compute the endocardial RV and LV end-diastolic area, length, 24-segment sphericity index, 24-segment transverse width and the following functional parameters: fractional area change; global longitudinal, free-wall and septal-wall strain; basal-apical-length, basal free-wall and basal septal-wall fractional shortening; septal-wall annular plane systolic excursion; 24-segment transverse-width fractional shortening; and LV end-diastolic and end-systolic volumes, stroke volume, cardiac output and ejection fraction. In addition, the RV/LV end-diastolic area ratio was computed. Using a control group of 200 normal fetuses, the mean and SD for each of the above cardiac measurements was used to compute the Z-scores for each measurement in each of the 108 study fetuses. Logistic regression analysis was then performed on the Z-score values to identify variables that separated the true CoA group from the FP-CoA group. RESULTS: Of the 108 study fetuses, 54 were confirmed postnatally to have true CoA and 54 were FP-CoA. Right/left area disproportion > 90th centile was present in 80% (n = 43) of the true-CoA fetuses and 76% (n = 41) of the FP-CoA fetuses. Fetuses with true CoA had a significantly greater number of associated cardiac abnormalities (93%, n = 50) compared with the FP-CoA fetuses (61%, n = 33) (P < 0.001). The most common associated malformations were bicuspid aortic valve (true CoA, 46% (n = 25) vs FP-CoA, 22% (n = 12); P < 0.01), aortic arch hypoplasia (true CoA, 31% (n = 17) vs FP-CoA, 11% (n = 6); P < 0.01), ventricular septal defect (true CoA, 33% (n = 18) vs FP-CoA, 11% (n = 6); P < 0.05) and mitral valve abnormality (true CoA, 30% (n = 16) vs FP-CoA, 4% (n = 2); P < 0.01). Logistic regression analysis identified 28 variables that correctly identified 96% (52/54) of the fetuses with true CoA, with a false-positive rate of 4% (2/54) and a false-negative rate of 4% (2/54). These variables included the epicardial size in the 4CV, size and shape of RV and LV, and abnormal contractility of RV and LV. The area under the receiver-operating-characteristics curve was 0.98 (SE, 0.023; 95% CI, 0.84-1). There was no significant difference in the percent of fetuses with RV/LV area disproportion between those with CoA and those that were FP-CoA. CONCLUSIONS: Speckle-tracking analysis of multiple ventricular measurements may be helpful to refine the diagnosis in fetuses that are suspected to have CoA prenatally. © 2020 International Society of Ultrasound in Obstetrics and Gynecology.

Quantitative evaluation of fetal right and left ventricular fractional area change using speckle-tracking technology.

OBJECTIVES: To measure, using speckle-tracking technology, the fractional area change (FAC) of the right and left ventricles in normal fetal hearts between 20 and 40 weeks of gestation. METHODS: The four-chamber view of the fetal heart was obtained in 200 normal fetuses between 20 and 40 weeks of gestation. FAC was computed from the ventricular areas (((end-diastolic area - end-systolic area)/end-diastolic area) × 100) for the right and left ventricles, and regressed against seven independent biometric and age variables. FAC was correlated with longitudinal fractional shortening (LFS) (((end-diastolic longitudinal length - end-systolic longitudinal length)/end-diastolic longitudinal length) × 100) obtained from the mid-ventricular basal-apical lengths of the right and left ventricular chambers and with transverse fractional shortening (TFS) (((end-diastolic transverse length - end-systolic transverse length)/end-diastolic transverse length) × 100) from three transverse positions (base, mid, apical) located within each ventricular chamber. To evaluate potential clinical utility, FAC, LFS and TFS results were examined in nine fetuses with a congenital heart defect (CHD). RESULTS: Regression analysis demonstrated significant associations between FAC and the independent biometric and age variables (R2  = 0.13-0.15). FAC was significantly correlated with LFS (R2  = 0.18-0.28) and TFS (R2  = 0.13-0.33). Examination of the fetuses with CHD revealed that six of the nine had abnormal FAC Z-score values for the index pathological ventricle. When abnormal LFS and TFS values were compared to the FAC in these fetuses, the FAC was either abnormally low or normal. CONCLUSIONS: This study reports results from measuring the FAC of the right and left ventricles, and demonstrates a correlation with LFS and TFS. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.

24-segment sphericity index: a new technique to evaluate fetal cardiac diastolic shape.

OBJECTIVE: Because of parallel circulation in the fetus and the differential effect that various disease states may have on the shape of the right and left ventricles, this study was conducted to evaluate the sphericity index (SI) of 24 transverse segments distributed from the base to the apex of each of the ventricular chambers. METHODS: Two hundred control fetuses were examined between 20 and 40 weeks of gestation. The displacement of the ventricular endocardium during the cardiac cycle was computed using offline speckle-tracking software. From the ASCII output of the analysis, we analyzed 24 end-diastolic transverse segments, distributed from the base to the apex of each ventricle, as well as the end-diastolic mid-basal-apical length. The SI was computed for each of the 24 segments by dividing the mid-basal-apical length by the transverse length for each segment. Regression analysis was performed against biometric measurements and gestational age according to last menstrual period and ultrasound. Eight fetuses, in which the four-chamber view appeared subjectively to demonstrate chamber disproportion, were evaluated as examples to demonstrate the utility of this technology. RESULTS: The SI for each segment was independent of gestational age and fetal biometric measurements. The SI of the right ventricle was significantly (P < 0.001) lower than that of the left ventricle for segments 1-18, suggesting that the right ventricle was more globular in shape than was the left ventricle at the base, mid and a portion of the apical segments of the chamber. Fetuses with various cardiac structural abnormalities and abnormal fetal growth had abnormal SI values that reflected either a more globular or a more flattened ventricular chamber. CONCLUSION: Determination of SI for each of 24 segments of the fetal right and left ventricles provides a comprehensive method to examine the shape of the ventricular chambers. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.

Right and left ventricular 24-segment sphericity index is abnormal in small-for-gestational-age fetuses.

OBJECTIVE: Fetuses with growth restriction have been reported to have an abnormal sphericity index (SI), which is indicative of the shape of the ventricular chambers of the heart. Our aim was to evaluate the SI for 24 transverse segments distributed from base to apex of the right (RV) and left (LV) ventricles to determine whether, in small-for-gestational-age (SGA) fetuses, the SI is abnormal at locations other than the basal segment. METHODS: We evaluated 30 SGA fetuses between 25 and 37 weeks of gestation. SI was computed for both ventricles by dividing the end-diastolic mid-basal-apical length by each of 24 end-diastolic transverse segmental widths, from base (Segment 1) to apex (Segment 24). For each ventricle, the Z-score and centile for the SI from each of the 24 segments were computed using the mean and SD from published equations. The 24-segment method, defining abnormal SI as values < 10th centile or > 90th centile, was compared with that of using only the basal segment by chi-square analysis to determine the number of fetuses identified with an abnormal SI. RESULTS: In 23 of the 30 (77%) SGA fetuses, at least one of the 24 transverse segments in one or both ventricles had an abnormal SI; in 17% of cases, both ventricles were affected, in 23% of cases only the RV was involved and in 37% of cases only the LV was involved. Compared with the 24-segment model, significantly fewer fetuses with an abnormal SI were identified using only basal Segment 1, from the RV base (58%, 7/12; P < 0.01) or only Segment 12, in the mid portion of the RV (50%, 6/12; P < 0.005). Combining measurements of Segment 1 and Segment 12 from the RV identified 83% of fetuses with at least one abnormal SI and was not significantly different from using the 24-segment model. Similarly, significantly fewer fetuses with an abnormal SI were identified using only LV basal Segment 1 (63%, 10/16; P < 0.006) or only Segment 12, in the mid portion of the LV (75%, 12/16; P < 0.03), when compared with the 24-segment model. Combining measurements of both LV Segment 1 and Segment 12 identified 81% (13/16) of fetuses with an abnormal SI and was not significantly different from using the 24-segment model. CONCLUSION: The 24-segment SI of RV and LV provides a comprehensive method with which to examine the shape of the ventricular chambers and identifies more SGA fetuses with an abnormal SI than are identified using only the basal segment SI. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.