Hypoplastic Right Heart Syndrome Research Articles

Abstract P1029: Abnormal Progenitor Cell Differentiation And Cardiomyocyte Proliferation In Hypoplastic Right Heart Syndrome

Pulmonary atresia with intact ventricular septum (PA-IVS) is a rare (4-8 per 100,000 live births) type of hypoplastic right heart syndrome (HRHS) where the right-sided structures in the heart are malformed. In PA-IVS, the pulmonary valve that acts to regulate the unidirectional flow of blood from the right ventricle (RV) to the lungs does not open, resulting in no connection between the RV and the pulmonary arteries. After surgical or catheter-based intervention, PA-IVS patients have clinical outcomes that range from single-ventricle palliation to a biventricular repair. Mechanisms underlying the spectrum of RV hypoplasia in PA-IVS are difficult to fully ascribe to an atretic pulmonary valve. There are no reliable animal models available for studying disease mechanisms of PA-IVS. In this study, we leverage patient-specific induced pluripotent stem cells (iPSCs) and single-cell RNA sequencing to elucidate cellular etiologies of ventricular hypoplasia in PA-IVS. PA-IVS iPSC-derived cardiomyocytes are less proliferative compared to controls under both static and cyclic stretch, suggesting that genetic factors may contribute to a spectrum of ventricular hypoplasia in PA-IVS. Single-cell transcriptomic analysis reveals that cell lineage determination towards second heart progenitors is suppressed, with enhanced differentiation into first heart field and epicardial lineages during cardiac differentiation. Additionally, biological pathways associated with cell proliferation and cell cycle progression are downregulated whereas mitochondrial activities are elevated in early cardiomyocytes originated from PA-IVS patients. In conclusion, abnormal cell lineage differentiation and cardiomyocyte proliferation may underlie the cellular and developmental etiologies of ventricular hypoplasia in HRHS.

Fetal pulmonary valvuloplasty for pulmonary atresia with intact ventricular septum: a single-center clinical experience.

Fetal pulmonary valvuloplasty for pulmonary atresia with intact ventricular septum: a single-center clinical experience.

The electrical heart axis in fetuses with congenital heart disease, measured with non-invasive fetal electrocardiography.

ObjectivesTo determine if the electrical heart axis in different types of congenital heart defects (CHD) differs from that of a healthy cohort at mid-gestation.MethodsNon-invasive fetal electrocardiography (NI-fECG) was performed in singleton pregnancies with suspected CHD between 16 and 30 weeks of gestation. The mean electrical heart axis (MEHA) was determined from the fetal vectorcardiogram after correction for fetal orientation. Descriptive statistics were used to determine the MEHA with corresponding 95% confidence intervals (CI) in the frontal plane of all fetuses with CHD and the following subgroups: conotruncal anomalies (CTA), atrioventricular septal defects (AVSD) and hypoplastic right heart syndrome (HRHS). The MEHA of the CHD fetuses as well as the subgroups was compared to the healthy control group using a spherically projected multivariate linear regression analysis. Discriminant analysis was applied to calculate the sensitivity and specificity of the electrical heart axis for CHD detection.ResultsThe MEHA was determined in 127 fetuses. The MEHA was 83.0° (95% CI: 6.7°; 159.3°) in the total CHD group, and not significantly different from the control group (122.7° (95% CI: 101.7°; 143.6°). The MEHA was 105.6° (95% CI: 46.8°; 164.4°) in the CTA group (n = 54), -27.4° (95% CI: -118.6°; 63.9°) in the AVSD group (n = 9) and 26.0° (95% CI: -34.1°; 86.1°) in the HRHS group (n = 5). The MEHA of the AVSD and the HRHS subgroups were significantly different from the control group (resp. p = 0.04 and p = 0.02).The sensitivity and specificity of the MEHA for the diagnosis of CHD was 50.6% (95% CI 47.5% - 53.7%) and 60.1% (95% CI 57.1% - 63.1%) respectively.ConclusionThe MEHA alone does not discriminate between healthy fetuses and fetuses with CHD. However, the left-oriented electrical heart axis in fetuses with AVSD and HRHS was significantly different from the control group suggesting altered cardiac conduction along with the structural defect.Trial registrationClinical trial registration number: NL48535.015.14.

Blood Flow Disturbance and Morphological Alterations Following the Right Atrial Ligation in the Chick Embryo.

Collectively known as congenital heart defects (CHDs), cardiac abnormalities at birth are the most common forms of neonatal defects. Being principally responsible for the heart‘s pumping power, ventricles are particularly affected by developmental abnormalities, such as flow disturbances or genomic defects. Hypoplastic Right Heart Syndrome (HRHS) is a rare disease where the right ventricle is underdeveloped. In this study, we introduce a surgical procedure performed on chick embryo, termed right atrial ligation (RAL) for disturbing hemodynamics within the right heart aiming in order to generate an animal model of HRHS. RAL is a new surgical manipulation, similar to the well-studied left atrial ligation (LAL) surgery but it induces the hemodynamic change into the right side of the heart. After inducing RAL, We utilized techniques such as Doppler ultrasound, x-ray micro-CT, histology, and computational fluid dynamics (CFD) analysis, for a comprehensive functional and structural analysis of a developing heart. Our results displayed that RAL does not induce severe flow disturbance and ventricular abnormalities consistent with clinical findings. This study allows us to better understand the hemodynamics-driven CHD development and sensitivities of ventricles under disturbed flows.

Probing single ventricle heart defects with patient-derived induced pluripotent stem cells and emerging technologies.

Single ventricle heart defects (SVHDs) are a severe type of congenital heart disease with poorly understood pathogenic mechanisms. New research using patient-specific induced pluripotent stem cells (iPSCs) as a cellular model is beginning to uncover genetic and cellular etiologies of SVHDs. Hypoplastic left heart syndrome (HLHS) is a type of SVHD that is characterized by an underdeveloped left ventricle and other malformations in the left side of the heart. Hypoplastic right heart syndrome (HRHS), the second type of SVHD, is characterized by an underdeveloped right heart, including malformed tricuspid and pulmonary valves. Despite a noticeable lack of research on SVHD, emerging technologies offer a promising future to further probe the genetic and cellular mechanisms of these diseases. Pediatric cardiovascular research is at the dawn of a new era in terms of what can be discovered with patient-specific iPSCs in conjunction with other technologies (e.g., organoids, single-cell genomics, CRISPR/Cas9 genome editing). In this review, we present recent approaches and findings utilizing patient-specific iPSCs to identify cellular mechanisms responsible for improper cardiac organogenesis in HLHS and HRHS.

Hypoplastic right heart syndrome

Congenital heart diseases (CHDs) are of two types-acyanotic and cyanotic. Acyanotic heart diseases include atrial septal defect ASD, ventricular septal defect VSD, patent ductus arteriosus PDA, coarctation of aorta and atrioventricular cushion defects. Cyanotic heart disease includes Fallot’s tetralogy, transposition of the great vessels, Total anomalous pulmonary venous return, Tricuspid atresia and single ventricle or hypoplastic left heart or hypoplastic right heart syndrome (HRHS). Hypoplastic right heart is a rarer condition than the hypoplastic left heart. Our patient had a cyanotic heart disease; presented to us with hypoplastic right heart, a very rare association consisting of pulmonary atresia combined with a hypoplastic right ventricle and well-developed pulmonary arteries. Early clinical diagnosis and surgical intervention saved this child.

Abstract 10252: State Wide Pregnancy Outcomes for Adolescents and Adults with Single-Ventricle Congenital Heart Disease - A 14 Year Review

Introduction: With advances in care, survival into adulthood of single-ventricle (SV) palliation is more frequent. Fertility and family planning in this setting is complex. In the general population, maternal mortality is 0.02%, post-partum hemorrhage (PPH) is 3.1% and pre-eclampsia is 7.5%. There are limited data on outcomes of pregnancies of women with SV physiology. This study reviews deliveries of SV mothers in Texas over the past 14 years. Methods: This is a retrospective review of the Texas Inpatient Discharge Dataset, an administrative dataset containing most hospital discharges. All discharges of females≥15 years old between 1/1/2006-12/31/2019 were reviewed. ICD-9/10 diagnosis codes consistent with Hypoplastic Left Heart Syndrome (HLHS), Double Inlet Ventricle (DIV)/Common Ventricle (CV), and Hypoplastic Right Heart Syndrome (HRHS)/Tricuspid Atresia (TA) were included. Pregnancy-related discharges were identified by ICD-9/10 codes. Descriptive and univariate statistics were utilized. Results: A total of 56 pregnancy-related discharges were identified, with 40 (71.4%) deliveries (Table). One (2.5%) was a twin gestation and 4(10%) had fetal demise. Number of annual deliveries increased from 0 in 2006 to 8 in 2019. Median gestational age was 37[IQR: 33.25-38] weeks, 7 (17.5%) had fetal anomalies and 7(17.5%) had poor fetal growth. Twelve (30%) underwent C-Section. Median length of stay was 3.5[2-5] days, 3(7.5%) mothers had PPH, 2(5%) required ventilator support, and there were no in-hospital mortalities. Conclusions: As the number of patients with SV surviving into adulthood increases, accurate counseling on risks of pregnancy is required. While these data cannot evaluate the outcomes for the delivered baby, they suggest favorable short-term outcomes for mothers with no in-hospital mortalities. Further research is needed to both understand outcomes for the delivered babies as well as potential longer-term sequelae for mothers.

Fetal cardiac intervention and perioperative management of fetus with hypoplastic right heart syndrome

Objective: To summarize the experience of perioperative management strategy of fetal pulmonary valvuloplasty (FPV) for hypoplastic right heart syndrome (HRHS). Methods: In the retrospective study of perioperative data, 13 fetuses of HRHS were treated with FPV in Qingdao Women and Children's Hospital from July 2018 to June 2019. Results: (1) The evaluation indexes of the right ventricle in 13 fetuses before FPV: the mean ratio of tricuspid/mitral annulus, right/left ventricular length, pulmonary/aortic annulus, and tricuspid inflow time/cardiac cycle were 0.81±0.04, 0.56±0.14, 0.69±0.06, and 0.35±0.03, respectively. (2) All pregnant mothers underwent general anesthesia. The basic fetal heart rate was (156±12) beats per minutes before FPV, and 9 fetuses showed bradycardia during the operation, and recovered to normal after drug resuscitation. On the first day after FPV, two cases had bradycardia and pregnancy was terminated. The fluctuation of systolic blood pressure of pregnant mother was less than 20%, and there was no significant difference between preoperative and intraoperative pulse pressure [(36.0±5.6) vs (35.8±6.9) mmHg (1 mmHg=0.133 kPa); t=8.102, P=0.951]. (3) All cases of HRHS fetus successfully underwent FPV. The average gestational age was (27.3±0.8) weeks. The average operation time was (23.2±1.0) minutes. The ratio of tricuspid to mitral annulus (t=-2.513, P=0.022) and the ratio of right to left ventricular length (t=-3.373, P=0.003) were significantly improved at 6 weeks postoperatively. Ten fetuses were delivered, and there was no death after early intervention. (4) Of 13 pregnant women, 3 cases were nausea and vomiting on the day of FPV operation, the treatment of the symptoms was improved by tropisetron; one case had tolerable abdominal pain and improved without special treatment. Pregnant women had no major complications such as cardiac failure, abortion and death. (5) Chromosome karyotype analysis and microarray analysis of amniotic fluid was retained during the operation. No typical chromosome abnormality or other abnormal genetic diagnosis was found. Conclusions: FPV colud be used as an effective intervention measure to promote the development of right ventricle in HRHS fetuses. The scientific management of multidisciplinary professional technical team in perioperative period is particularly important to ensure the success of FPV and the safety of pregnant women and fetuses.

Minor alleles of genetic variants in second heart field increase the risk of hypoplastic right heart syndrome

Hypoplastic right heart syndrome(HRHS) is characterized by hypoplastic right ventricle (RV); Numerous transcriptional cascades in the second heart field (SHF) regulate RVdevelopment. The relationship of SHF gene variants with human HRHS remains unknown. The whole lengths of 17 SHF genes were sequenced in 16 HRHS, and the selected single-nucleotide variants (SNVs) were then genotyped in HRHS, other congenital heart disease (CHD) and healthy control. Luciferase assay was performed to verify the effect of FOXC2: rs34221221A>GandTBX20: rs59854940C>Gat the transcription level. There were 151 (12.86%) novel SNVs after sequence analysis, of which three were in exons (one was synonymous SNV and two were nonsynonymous SNVs), two in promoter, and most SNVs (89.95%) were in intronic regions. Genotype analyses revealed that the minor alleles of FOXC2: rs34221221 A>G and TBX20: rs59854940 C>G could increase HRHS risk (P<0.05), but not in other CHD or healthy control. Luciferase assay showed that the minor G allele in rs34221221 significantly increased FOXC2 transcription while in rs59854940 it decreased TBX20 transcription significantly. Novel variants of SHF gene associated with HRHS were identified. Minor alleles in two variants from FOXC2 and TBX20 could increase the risk of HRHS.

First-trimester ultrasound screening for prenatal diagnosis of fetal congenital heart disease

Objective To investigate the value of standardized ultrasound screening in diagnosis of fetal congenital heart disease (CHD) during the first trimester. Methods This study retrospectively analyzed the clinical data of 8 383 fetuses who received ultrasound screening during the first trimester in the Dongguan Maternal and Child Health Hospital from September 2015 to December 2016. Standardized ultrasound was performed to observe fetal heart position, apical direction, apical four-chamber view, three vessels and trachea view and the thickness of nuchal translucency (NT). Fetuses with thickened NT or fetal CHD observed during the first and second trimester were followed up. Pregnancy outcomes and the growth of newborns within one year after birth were recorded and analyzed. Pathological results after the termination of pregnancy were compared with the results of routine karyotyping and chromosome microarray analysis (CMA). Results (1) A total of 27 cases of fetal CHD were identified during the first trimester giving a detection rate of 0.32% (27/8 383). These included ten (37.0%) of single atrium and/or single ventricle, seven (25.9%) of endocardial cushion defect (including two complicated by persistent arterial trunk), three (11.1%) of hypoplastic right heart syndrome, three (11.1%) of interventricular septal defect, two (7.4%) of hypoplastic left heart syndrome, one (3.7%) of mirror-image dextrocardia and one (3.7%) of right atrial enlargement and severe tricuspid regurgitation. Nineteen out of the 27 cases had NT thickening (NT≥3.0 mm) and 17 of them had a cystic hygroma (NT≥6.0 mm). Among the 27 cases, 22 were terminated in the first trimester which autopsy results were consistent with ultrasound and the other five were rescreened during the second trimester. Thirteen out of the 27 cases received chorionic villus sampling, and seven of them were found to have chromosomal abnormalities by karyotyping and CMA, among whom one was microdeletion of 22q11. (2) Twenty-one cases of CHD were detected in the second-trimester ultrasound screening, including five initially identified in the first trimester. These cases included four (19.0%) of complex cardiac malformations (with three or more malformations), four (19.0%) of interventricular septal defect, three (14.3%) of dextroaortic arch, left subclavian artery vagus and 'U' shaped vascular ring, three (14.3%) of hypoplastic right heart syndrome (including one complicated by coronary artery-right ventricular fistula and one by interventricular septal defect), two (9.5%) of transposition of the great arteries, two (9.5%) of tetralogy of Fallot, one (4.8%) of hypoplastic left heart syndrome, one (4.8%) of Taussig-Bing anomaly and one (4.8%) of coarctation of the aorta. Among the 16 cases first identified in the second trimester, eight had NT thickening, including one with cystic hygroma. Among the 21 cases, two were lost to follow-up after being transferred to another hospital; four with negative results in karyotype analysis and CMA were delivered vaginally at term (37-40 gestational weeks) with 1-min Apgar scores of ten points and postpartum ultrasound of the baby was consistent with the second-trimester ultrasound screening; 15 were terminated and the autopsy confirmed those findings in the second-trimester ultrasound screening. Eleven out of the 21 cases received amniocentesis and five of them were found to be abnormal according to karyotype analysis and CMA, including one of microdeletion of 22q11. Conclusions Standardized first-trimester ultrasound screening is important and of great clinical value in the diagnosis of fetal CHD. Increased NT thickness could be a key indicator of fetal CHD and chromosomal abnormalities in early pregnancy. CMA may facilitate detecting the abnormality of genetic material in fetuses with normal chromosome karyotype. Key words: Heart defects, congenital; Ultrasonography, prenatal; Pregnancy trimester, first; Microarray analysis

Copy number variants in hypoplastic right heart syndrome.

Hypoplastic right heart syndrome (HRHS) is a rare congenital defect characterized by underdeveloped and malformed structures of the right heart. Familial recurrence of HRHS indicates genetic factors contribute to its etiology. Our study investigates the presence of copy number variants (CNVs) in HRHS cases. We genotyped 42 HRHS cases identified from live births throughout California (2003-2010) using the Illumina HumanOmni2.5-8 array. We identified 14 candidate CNVs in 14 HRHS cases (33%) based on the genes included in the CNVs and their functions. Duplications overlapping part of ERBB4 were identified in two unrelated cases. ERBB4 is a neuregulin receptor with a pivotal role in cardiomyocyte differentiation and heart development. We also described a 7.5 Mb duplication at 16q11-12. Multiple genes in the duplicated region have previously been linked to heart defects and cardiac development, including RPGRIP1L, RBL2, SALL1, and MYLK3. Of the 14 validated CNVs, we identified four CNVs in close proximity to genes linked to the Wnt signaling pathway. This study expands on our previous work supporting the role of genetics in HRHS. We identified CNVs affecting crucial genes and signaling pathways involved in right heart development. ERBB4 and duplication of the 16q11-12 region are important areas for future investigation.

Cerebrovascular hemodynamics in fetuses with congenital heart disease.

It is hypothesized that diminished cerebral vascular resistance or the "brain sparing effect" is associated with fetuses with complex congenital heart defects (CHD) and may affect their neurodevelopmental outcome. An alternative explanation is that it is related to the location, cardiac output, pressure, and resistance in left heart obstructive CHDs. We sought to determine the effects of various left and right heart obstructive defects on the cerebral and placental hemodynamics and to evaluate the utility of these variables for the assessment and prognosis of CHDs. A total of 290 fetal echocardiograms were reviewed, including 91 fetuses with CHD and 199 normal ones. The CHD fetuses were divided into four groups, that is, left-sided obstructive lesions (LSOL), hypoplastic left heart syndrome (HLHS), right-sided obstructive lesions (RSOL), and hypoplastic right heart syndrome (HRHS). The pulsatility index of middle cerebral artery (MCA-PI) and umbilical artery (UA-PI) were measured by pulse-wave Doppler, and their Z scores were also derived. Cerebroplacental ratio (CPR) was calculated as: CPR=MCA-PI/UA-PI. There was no significant difference in MCA-PI between the 4 CHD and normal control groups (P>.05). However, MCA-PI and Z score decreased in aortic stenosis but not in interrupted aortic arch or coarctation subgroups, whereas they increased in pulmonary atresia but not pulmonary stenosis or tetralogy of Fallot subgroups compared with normal group (P<.05). There was no significant difference in CPR between any study group or subgroup and normal control group. Our study suggests MCA-PI is lower in aortic stenosis and high in pulmonary atresia but not significantly different in other LSOL, HLHS, RSOL, and HRHS. MCA-PI regulation in CHD is probably more associated with left and right outflow obstruction, location of the obstruction, and hemodynamics rather than "brain sparing effect" or preferential shunting of blood to the fetal brain, heart, and adrenals in the stressed fetus (eg, IUGR). CPR may not be a sensitive measure for the effect of CHDs and their severity on cerebral and placental circulation.

Hypoplastic Left Heart Syndrome Sequencing Reveals a Novel NOTCH1 Mutation in a Family with Single Ventricle Defects.

Hypoplastic left heart syndrome (HLHS) has been associated with germline mutations in 12 candidate genes and a recurrent somatic mutation in HAND1 gene. Using targeted and whole exome sequencing (WES) of heart tissue samples from HLHS patients, we sought to estimate the prevalence of somatic and germline mutations associated with HLHS. We performed Sanger sequencing of the HAND1 gene on 14 ventricular (9 LV and 5 RV) samples obtained from HLHS patients, and WES of 4 LV, 2 aortic, and 4 matched PBMC samples, analyzing for sequence discrepancy. We also screened for mutations in the 12 candidate genes implicated in HLHS. We found no somatic mutations in our HLHS cohort. However, we detected a novel germline frameshift/stop-gain mutation in NOTCH1 in a HLHS patient with a family history of both HLHS and hypoplastic right heart syndrome (HRHS). Our study, involving one of the first familial cases of single ventricle defects linked to a specific mutation, strengthens the association of NOTCH1 mutations with HLHS and suggests that the two morphologically distinct single ventricle conditions, HLHS and HRHS, may share a common molecular and cellular etiology. Finally, somatic mutations in the LV are an unlikely contributor to HLHS.

Rare copy number variants in a population-based investigation of hypoplastic right heart syndrome.

Hypoplastic right heart syndrome (HRHS) is a rare congenital defect characterized by underdevelopment of the right heart structures commonly accompanied by an atrial septal defect. Familial HRHS reports suggest genetic factor involvement. We examined the role of copy number variants (CNVs) in HRHS. We genotyped 32 HRHS cases identified from all New York State live births (1998-2005) using Illumina HumanOmni2.5 microarrays. CNVs were called with PennCNV and prioritized if they were ≥20 Kb, contained ≥10 SNPs and had minimal overlap with CNVs from in-house controls, the Database of Genomic Variants, HapMap3, and Childrens Hospital of Philadelphia database. We identified 28 CNVs in 17 cases; several encompassed genes important for right heart development. One case had a 2p16-2p23 duplication spanning LBH, a limb and heart development transcription factor. Lbh mis-expression results in right ventricular hypoplasia and pulmonary valve defects. This duplication also encompassed SOS1, a factor associated with pulmonary valve stenosis in Noonan syndrome. Sos1-/- mice display thin and poorly trabeculated ventricles. In another case, we identified a 1.5 Mb deletion associated with Williams-Beuren syndrome, a disorder that includes valvular malformations. A third case had a 24 Kb deletion upstream of the TGFβ ligand ITGB8. Embryos genetically null for Itgb8, and its intracellular interactant Band 4.1B, display lethal cardiac phenotypes. To our knowledge, this is the first study of CNVs in HRHS. We identified several rare CNVs that overlap genes related to right ventricular wall and valve development, suggesting that genetics plays a role in HRHS and providing clues for further investigation. Birth Defects Research 109:16-26, 2017. © 2016 Wiley Periodicals, Inc.

TCT-429 Fetal Pulmonary Valvuloplasty. In-Utero and Post-Natal Outcomes

There is a paucity of data regarding the feasibility, safety and efficacy of fetal pulmonary valvuloplasty (FPV) for pulmonary atresia or stenosis with intact interventricular septum (PA/PS/IVS) and evolving hypoplastic right heart syndrome (HRHS) diagnosed in-utero. We report in-utero and post

Characteristics of echocardiographic imaging and pathology in fetuses with hypoplastic right heart syndrome

Objective To detect the echocardiographic and pathologic characteristics of hypoplastic right heart syndrome (HRHS) during fetal period.Methods The pathomorphology of fetal heart specimens with HRHS was detected,and the sections of the right ventricle,pulmonary artery and pulmonary conus were studied by light microscopy.Prenatal echocardiographic images were analysed retrospectively.Results Ten formalin-fixed necropsy heart specimens with HRHS were selected.Among the specimens,transverse diameter and vertical diameter of right ventricular and pulmonary artery measured values was smaller than those of control group,the difference was statistically significant (P ＜0.05),tricuspid regurgitation area and regurgitation velocity was significantly greater than that in control group and the difference was statistically significant(P ＜0.05).Histological change of right ventricular myocardial fibrosis was present in 100％.The coincidence of prenatal echocardiographic diagnosis was 100％.Conclusions There is higher accuracy of prenatal echocardiography in diagnosing fetal HRHS.Marked histological abnormalities in right ventricular myocardium,pulmonary artery and pulmonary conus with HRHS exist excepting morphologic abnormalities. Key words: Ultrasonography, prenatal; Fetus; Heart defects, congenital; Hypoplastic right heart syndrome

Clinical study of cerebrovascular blood flow dynamics in fetus with congenital heart disease

Objective To determine whether CHD modify cerebrovascular flow dynamics in CHD fetuses,and the influence on different types of CHD.Methods Two hundred normal fefuses and 159 fetuses who were diagnosed CHD by prenatal echocardiogram were studied.CHD fetuses were divided into 6 groups according to hemodynamics:hypoplastic left heart syndrome(HLHS,n=23),left-sided obstructive lesions(LSOL,n=19),hypoplastic right heart syndrome(HRHS,n=15),right-sided obstructive lesions (RSOL,n=33),septal defect(SD,n=36),conotruneal defects(CTD,n=33).The pulsatility index(PI) and the cerebroplacental Doppler ratio(CPR)of the middle cerebral artery(MCA)and umbilical artery(UA) in normal and CHD group were measured by color Doppler flow system.Results MCA-PI and CPR in HLHS,HRHS,RSOL,CTD and SD groups all decreased compared with normal fetuses(P 0.05).Conclusions Fetuses with CHD had decreasing eerebrovascular impedance.Different types of CHD had different levels of eerebrovascular impedance,which indicated that different types of CHD induced different levels of cerebrovascular circulationcompensation. Key words: Ultrasonography,prenatal; Heart defects,congenital; Middle cerebral artery; Hemodynamic phenomena

Evaluation of the structure of tricuspid valve with three dimensional echocardiography in hypoplastic right ventricle

Objective To reveal the character of tricuspid valve in hypoplastic right ventrieular heart syndrome （HPRVHS） using 3-dimensional echocardiography（3DE）. Methods Twenty eight patients with HPRVHS were included in the study, and they were divided into two groups according the degree of tricuspid regurgitation. Eighteen normal children were included as the control. Volume of right ventricle（VRV）, area of tricuspid annulus（TVA ）, proportion of the leaflets and the distance from tips of leaflets to the nearest papillary muscle were measured with 3DE. These data was standardized by body surface area. Results The volume of right ventricle in HPRVHS was significantly less than that in normal group. The area of tricuspid annulus was significantly correlated with volume of right ventricle（ r = 0. 90, P 0. 0001）. In the tricuspid regurgitation group, the proportion of area of anterior leaflet to area of tricuspid annulus was significantly higher than non-regurgitation group and normal group（ P〈0.0001 ）. Respectively, the proportion of the area of posterior leaflet to the area of tricuspid annulus in regurgitation group was significantly less than normal and non- regurgitation group. The distance from tips of leaflets was significantly shorter in HPRVHS than in normal group. Furthermore,the distance from the tip of septal leaflet to the nearest papillary muscle was shorter in regurgitation group than non-regurgitation group （ P = 0. 0023）. Conclusions 3DE could be applied for evaluating the pathologic change of tricuspid valve in congenital heart disease. In HPRVHS, hypoplastic of posterior leaflet and shortness of the cords of septal leaflet could be the cause of tricuspid regurgitation. Key words: Echocardiography, three-dimensional ; Heart defects, congenital; Hypoplastic tricuspid valve

Prenatal Diagnosis of Bilateral Ventriculocoronary Fistulas With Hypoplasia of the Left Ventricle

Fetal echocardiography and color Doppler sonography have shown that most heart defects can be reliably diagnosed in utero by associated hemodynamic changes. Congenital ventriculocoronary fistulas associated with hypoplastic right heart syndrome (HRHS) and hypoplastic left heart syndrome (HLHS) have been described in the prenatal and neonatal periods, but little attention has been paid to their incidence and hemodynamic changes. There have been only a few reports of prenatal diagnosis of ventriculocoronary communications in HRHS and HLHS. Here we report prenatal diagnosis of HLHS and fistulas between the left ventricle and both the right and left coronary arteries to the pulmonary artery with a muscular ventricular septal defect (VSD) in a fetus at 23 weeks' gestation.