Mitral Annular Disjunction: An Under-Recognized Entity in Pediatrics.

Mitral annular disjunction (MAD) is a rare and under-recognized entity in the pediatric population. We present 2 cases of MAD in previously healthy pediatric patients and highlight clinical scenarios where MAD should be suspected.

Neonatal Survival After Serial Amnioinfusions for Bilateral Renal Agenesis: The Renal Anhydramnios Fetal Therapy Trial.

Importance: Early anhydramnios during pregnancy, resulting from fetal bilateral renal agenesis, causes lethal pulmonary hypoplasia in neonates. Restoring amniotic fluid via serial amnioinfusions may promote lung development, enabling survival. Objective: To assess neonatal outcomes of serial amnioinfusions initiated before 26 weeks' gestation to mitigate lethal pulmonary hypoplasia. Design, Setting, and Participants: Prospective, nonrandomized clinical trial conducted at 9 US fetal therapy centers between December 2018 and July 2022. Outcomes are reported for 21 maternal-fetal pairs with confirmed anhydramnios due to isolated fetal bilateral renal agenesis without other identified congenital anomalies. Exposure: Enrolled participants initiated ultrasound-guided percutaneous amnioinfusions of isotonic fluid before 26 weeks' gestation, with frequency of infusions individualized to maintain normal amniotic fluid levels for gestational age. Main Outcomes and Measures: The primary end point was postnatal infant survival to 14 days of life or longer with dialysis access placement. Results: The trial was stopped early based on an interim analysis of 18 maternal-fetal pairs given concern about neonatal morbidity and mortality beyond the primary end point despite demonstration of the efficacy of the intervention. There were 17 live births (94%), with a median gestational age at delivery of 32 weeks, 4 days (IQR, 32-34 weeks). All participants delivered prior to 37 weeks' gestation. The primary outcome was achieved in 14 (82%) of 17 live-born infants (95% CI, 44%-99%). Factors associated with survival to the primary outcome included a higher number of amnioinfusions (P = .01), gestational age greater than 32 weeks (P = .005), and higher birth weight (P = .03). Only 6 (35%) of the 17 neonates born alive survived to hospital discharge while receiving peritoneal dialysis at a median age of 24 weeks of life (range, 12-32 weeks). Conclusions and Relevance: Serial amnioinfusions mitigated lethal pulmonary hypoplasia but were associated with preterm delivery. The lower rate of survival to discharge highlights the additional mortality burden independent of lung function. Additional long-term data are needed to fully characterize the outcomes in surviving neonates and assess the morbidity and mortality burden. Trial Registration: ClinicalTrials.gov Identifier: NCT03101891.

Fetal circulatory physiology and brain development in complex congenital heart disease: A multi-modal imaging study.

OBJECTIVE: Fetuses with complex congenital heart disease have altered physiology, contributing to abnormal neurodevelopment. The effects of altered physiology on brain development have not been well studied. We used multi-modal imaging to study fetal circulatory physiology and brain development in hypoplastic left heart syndrome (HLHS) and d-transposition of the great arteries (TGA). METHODS: This prospective, cross-sectional study investigated individuals with fetal congenital heart disease and controls undergoing fetal echocardiography and fetal brain MRI. MRI measured total brain volume and cerebral oxygenation by the MRI quantification method T2*. Indexed cardiac outputs (CCOi) and vascular impedances were calculated by fetal echocardiography. Descriptive statistics assessed MRI and echocardiogram measurement relationships by physiology. RESULTS: Sixty-six participants enrolled (control = 20; HLHS = 25; TGA = 21), mean gestational age 33.8 weeks (95% CI: 33.3-34.2). Total brain volume and T2* were significantly lower in fetuses with cardiac disease. CCOi was lower in HLHS, correlating with total brain volume - for every 10% CCOi increase, volume increased 8 mm3 (95% CI: 1.78-14.1; p = 0.012). Echocardiography parameters and cerebral oxygenation showed no correlation. TGA showed no CCOi or aortic output correlation with MRI measures. CONCLUSIONS: In HLHS, lower cardiac output is deleterious to brain development. Our findings provide insight into the role of fetal cardiovascular physiology in brain health.

Congenitally Corrected Transposition of the Great Arteries: Fetal Diagnosis, Associations, and Postnatal Outcome: A Fetal Heart Society Research Collaborative Study.

Background Fetal diagnosis of congenitally corrected transposition of the great arteries (ccTGA) has been increasingly reported; however, predictors of clinical outcomes remain underexplored. We undertook a multicenter, retrospective study to investigate natural history, associated anomalies, and outcomes of fetal ccTGA. Methods and Results Fetuses with ccTGA diagnosed from January 2004 to July 2020 within 20 North American programs were included. Fetuses with severe ventricular hypoplasia thought to definitively preclude biventricular repair were excluded. We included 205 fetuses diagnosed with ccTGA at a median gestational age of 23 (interquartile range, 21-27) weeks. Genetic abnormalities were found in 5.9% tested, with extracardiac anomalies in 6.3%. Associated cardiac defects were diagnosed in 161 (78.5%), with atrioventricular block in 23 (11.3%). On serial fetal echocardiogram, 39% demonstrated a functional or anatomic change, most commonly increased tricuspid regurgitation (6.7%) or pulmonary outflow obstruction (11.1%). Of 194 fetuses with follow-up, 26 were terminated, 3 experienced fetal death (2 with atrioventricular block), and 165 were live-born. Of 158 with postnatal data (median follow-up 3.7 years), 10 (6.6%) had death/transplant before 1 year. On univariable analysis, fetal factors associated with fetal death or death/transplant by 1 year included ≥ mild tricuspid regurgitation, pulmonary atresia, aortic obstruction, fetal arrhythmia, and worsening hemodynamics on serial fetal echocardiogram (defined as worse right ventricular function, tricuspid regurgitation, or effusion). Conclusions Associated cardiac lesions and arrhythmias are common in fetal ccTGA, and functional changes commonly occur through gestation. Worse outcomes are associated with fetal tricuspid regurgitation (≥mild), any arrhythmia, pulmonary atresia, aortic obstruction, and worsening hemodynamics on serial echocardiograms. These findings can inform prenatal counseling and perinatal management planning.

Comparison of Adverse Clinical Outcomes in Children Hospitalized for Myocarditis with and Without COVID-19.

We used a nationally representative database of the US, which included 1995 myocarditis cases, among whom 620 children had COVID-19. While the risk of in-hospital mortality was not higher, illness severity and length of hospital stay were higher in patients with myocarditis and COVID-19 than those without COVID-19.

Fetal Echocardiographic Z Score Pilot Project: Study Design and Impact of Gestational Age and Variable Type on Reproducibility of Measurements Within and Across Investigators.

BACKGROUND: Fetal echocardiography is widely available, but normative data are not robust. In this pilot study, the authors evaluated (1) the feasibility of prespecified measurements in a normal fetal echocardiogram to inform study design and (2) measurement variability to assign thresholds of clinical significance and guide analyses in larger fetal echocardiographic Z score initiatives. METHODS: Images from predefined gestational age groups (16-20, >20-24, >24-28, and >28-32 weeks) were retrospectively analyzed. Fetal echocardiography expert raters attended online group training and then independently analyzed 73 fetal studies (18 per age group) in a fully crossed design of 53 variables; each observer repeated measures for 12 fetuses. Kruskal-Wallis tests were used to compare measurements across centers and age groups. Coefficients of variation (CoVs) were calculated at the subject level for each measurement as the ratio of SD to mean. Intraclass correlation coefficients were used to show inter- and intrarater reliabilities. Cohen's d > 0.8 was used to define clinically important differences. Measurements were plotted against gestational age, biparietal diameter, and femur length. RESULTS: Expert raters completed each set of measurements in a mean of 23 ± 9 min/fetus. Missingness ranged from 0% to 29%. CoVs were similar across age groups for all variables (P < .05) except ductus arteriosus mean velocity and left ventricular ejection time, which were both higher at older gestational age. CoVs were >15% for right ventricular systolic and diastolic widths despite fair to good repeatability (intraclass correlation coefficient > 0.5); ductal velocities and two-dimensional measures, left ventricular short-axis dimensions, and isovolumic times all had high CoVs and high interobserver variability despite good to excellent intraobserver agreement (intraclass correlation coefficient > 0.6). CoVs did not improve when ratios (e.g., tricuspid/mitral annulus) were used instead of linear measurements. Overall, 27 variables had acceptable inter- and intraobserver repeatability, while 14 had excessive variability between readers despite good intraobserver agreement. CONCLUSIONS: There is considerable variability in fetal echocardiographic quantification in clinical practice that may affect the design of multicenter fetal echocardiographic Z score studies, and not all measurements may be feasible for standard normalization. As missingness was substantial, a prospective design will be needed. Data from this pilot study may aid in the calculation of sample sizes and inform thresholds for distinguishing clinically significant from statistically significant effects.

Impact of congenital heart disease on outcomes among pediatric patients hospitalized for COVID-19 infection.

BACKGROUND: COVID-19 infection is generally regarded as an acute self-limiting illness in children, but it can cause significant morbidity and mortality in both healthy and high-risk children. There are limited data on the outcomes of children with congenital heart disease (CHD) and COVID-19. This study aimed to examine the risks of mortality, in-hospital cardiovascular and non-cardiovascular complications in this patient population. METHODS: We analyzed data from hospitalized pediatric patients from 2020 using the nationally representative National Inpatient Sample (NIS). Children hospitalized for COVID-19 were included, and weighted data were used to compare in-hospital mortality and morbidities between children with and without CHD. RESULTS: Out of 36,690 children admitted with a diagnosis of COVID-19 infection(ICD-10 code:U07.1 and B97.29) during calendar year 2020, 1240 (3.4%) had CHD. The risk of mortality in children with CHD was not significantly higher than those without CHD(1.2% vs. 0.8%, p = 0.50), with adjusted OR (aOR) of 1.7 (95% CI: 0.6-5.3). Tachyarrhythmias and heart block were more likely in CHD children with an aOR of 4.2 (95% CI: 1.8-9.9) and aOR of 5.0 (95% CI: 2.4-10.8), respectively. Similarly, respiratory failure [aOR = 2.0 (1.5-2.8)], respiratory failure requiring non-invasive mechanical ventilation [aOR = 2.7 (1.4-5.2)] and invasive mechanical ventilation [aOR = 2.6 (1.6-4.0)], and acute kidney injury [aOR = 3.4 (2.2-5.4)] were all significantly higher among patients with CHD. Median length of hospital stay in children with CHD was longer than those without CHD [5 days (IQR: 2-11) vs. 3 days (IQR: 2-5), p = < 0.001]. CONCLUSIONS: Children with CHD hospitalized with COVID-19 infection were at increased risk of serious cardiovascular and non-cardiovascular adverse clinical outcomes. They also had increased length of hospital stay and utilization of healthcare resources.

Association of Body Mass Index With Clinical Features and Outcomes in Adults With Fontan Palliation.

Background With improving survival of patients with single ventricle physiology who underwent Fontan palliation, there is also an increase in the prevalence of overweight and obesity in these patients. This tertiary care single-center study aims to determine the association of body mass index (BMI) with the clinical characteristics and outcomes in adults with Fontan. Methods and Results Adult patients (aged ≥18 years) with Fontan who were managed at a single tertiary care center between January 1, 2000, and July 1, 2019, and had BMI data available were identified via retrospective review of medical records. Univariate and multivariable (after adjusting for age, sex, functional class, and type of Fontan) linear and logistic regression, as appropriate, were utilized to evaluate associations between BMI and diagnostic testing and clinical outcomes. A total of 163 adult patients with Fontan were included (mean age, 29.9±9.08 years), with a mean BMI of 24.2±5.21 kg/m2 (37.4% of patients had BMI ≥25 kg/m2). Echocardiography data were available for 95.7% of patients, exercise testing for 39.3% of patients, and catheterization for 53.7% of patients. Each SD increase in BMI was significantly associated with decreased peak oxygen consumption (P=0.010) on univariate analysis and with increased Fontan pressure (P=0.035) and pulmonary capillary wedge pressure (P=0.037) on multivariable analysis. In addition, BMI ≥25 kg/m2 was independently associated with heart failure hospitalization (adjusted odds ratio [AOR], 10.2; 95% CI, 2.79-37.1 [P<0.001]) and thromboembolic complications (AOR, 2.79; 95% CI, 1.11-6.97 [P=0.029]). Conclusions Elevated BMI is associated with poor hemodynamics and worse clinical outcomes in adult patients with Fontan. Whether elevated BMI is the cause or consequence of poor clinical outcomes needs to be further established.

Expected small left heart size in the presence of congenital diaphragmatic hernia: Fetal values and Z-scores for infants confirmed to have no heart disease postnatally.

Objectives: In fetuses with left-sided congenital diaphragmatic hernia (CDH), left heart structures may appear small, but usually normalize after birth in the absence of structural cardiac anomalies. To decrease the possibility of an erroneous diagnosis of structural heart disease, we identify normal values for left heart structures in the presence of left CDH and secondarily investigate the relationship of left heart size and survival to neonatal hospital discharge. Methods: Left heart structures [mitral valve (MV) and aortic valve (AoV) annulus diameter, left ventricle (LV) length and width] were measured by fetal echocardiogram in fetuses with left CDH and no congenital heart disease. We generated linear regression models to establish the relationship of gestational age for each left heart structure using data from fetuses who survived after birth. We calculated z-scores (normalized to gestational age), and assessed the relationship of survival to the size of each structure. Results: One hundred forty-two fetuses underwent fetal echocardiogram (median 25 weeks' gestation, IQR 23, 27 weeks). Left heart structures were deemed small when using published normative data from unaffected fetuses (z-scores: MV -1.09 ± 1.35, AoV -2.12 ± 1.16, LV length -1.36 ± 1.24, LV width -4.79 ± 0.79). CDH-specific models derived from log-transformed values yielded left-shifted distributions, reflecting the small structures (mean z-score lower by: MV 0.99 ± 0.30, AoV 2.04 ± 0.38, LV length 1.30 ± 0.36, and LV width 4.69 ± 0.28; p < 0.0001 for all comparisons). Non-survivors had worse z-scores than survivors for all measurements, but this did not reach statistical significance. Conclusions: Log-transformed linear models generated new normative data for fetal left heart structures in left CDH, which may be used to allay antenatal concerns regarding structural left heart anomalies. There were no significant differences in z-scores between survivors and non-survivors, suggesting that in the absence of true structural disease, cardiac evaluation is not predictive in isolation and that causes of mortality are likely multifactorial in this population.

Atrial Appendage Anastomosis in Hypoplastic Left Heart Syndrome With Restrictive Atrial Septum: A Novel Approach.

Intact atrial septum (IAS), occurring in ∼10% of patients with hypoplastic left heart syndrome (HLHS), conveys significant neonatal morbidity and mortality. Perinatal interventions have been described, but outcomes remain poor. We present a fetus with HLHS with IAS who underwent immediate novel postnatal atrial appendage anastomosis, thus achieving rapid left atrial decompression. (Level of Difficulty: Advanced.).

Pulmonary artery acceleration time in young children is determined by heart rate and transpulmonary gradient but not by pulmonary blood flow: A simultaneous echocardiography-cardiac catheterization study.

INTRODUCTION: Pulmonary artery acceleration time (PAAT) is considered useful for the non-invasive evaluation of pulmonary artery pressure (PAP) and pulmonary vascular resistance (PVR). PAAT is dependent on PAP, PVR, pulmonary artery compliance, stroke volume, and heart rate. Its relative dependency on these determinants may differ between young and older children, raising uncertainty regarding its utility in young children. We aim to identify the primary determinants of the PAAT in children less than 36 months undergoing cardiac catheterization and its utility for the diagnosis of elevated PVR. METHODS: We prospectively studied 42 children undergoing cardiac catheterization and simultaneous echocardiography. We determined the correlations of PAAT to the above-mentioned determinants and evaluated receiver operator characteristic (ROC) curves for diagnosis of PVR indexed to body surface area (PVRi) ≥3 Wu*m2 . RESULTS: Median age was 11.5 (IQR 5.2, 21.2) months. Moderate correlations were found between PAAT and mean PAP (R = -.66, p < .001), PVRi (R = -.54, p = .004), pulmonary artery compliance (R = .65, p < .001), transpulmonary gradient (R = -.67, p < .001), stroke volume (R = .61, p = .002), and heart rate (R = -.63, p < .001). In multivariate regression modeling, only transpulmonary gradient and heart rate were independent determinants of PAAT. PAAT ≤77 msec had acceptable utility for diagnosing PVRi ≥ 3 Wu*m2 (AUC .8 [.64, .95], n = 36), low sensitivity (59%), and excellent specificity (94%). CONCLUSION: Transpulmonary gradient and heart rate, but not pulmonary blood flow, are important determinants of PAAT in children <36 months undergoing cardiac catheterization. PAAT has low sensitivity for diagnosing elevated PVRi, therefore, should not be solely relied upon in screening for elevated PVRi in young children.

Care Levels for Fetal Therapy Centers.

Fetal therapies undertaken to improve fetal outcome or to optimize transition to neonate life often entail some level of maternal, fetal, or neonatal risk. A fetal therapy center needs access to resources to carry out such therapies and to manage maternal, fetal, and neonatal complications that might arise, either related to the therapy per se or as part of the underlying fetal or maternal condition. Accordingly, a fetal therapy center requires a dedicated operational infrastructure and necessary resources to allow for appropriate oversight and monitoring of clinical performance and to facilitate multidisciplinary collaboration between the relevant specialties. Three care levels for fetal therapy centers are proposed to match the anticipated care complexity, with appropriate resources to achieve an optimal outcome at an institutional and regional level. A level I fetal therapy center should be capable of offering fetal interventions that may be associated with obstetric risks of preterm birth or membrane rupture but that would be very unlikely to require maternal medical subspecialty or intensive care, with neonatal risks not exceeding those of moderate prematurity. A level II center should have the incremental capacity to provide maternal intensive care and to manage extreme neonatal prematurity. A level III therapy center should offer the full range of fetal interventions (including open fetal surgery) and be able manage any of the associated maternal complications and comorbidities, as well as have access to neonatal and pediatric surgical intervention including indicated surgery for neonates with congenital anomalies.

Current State of Fetal Heart Disease Counseling and Training: Room for Improvement? : Endorsed by the Fetal Heart Society.

We sought to describe the fellowship experiences and current practice habits of pediatric cardiologists who counsel patients with fetal heart disease (FHD) and to identify fellowship experiences related to FHD counseling perceived as valuable by respondents as well as opportunities for improvement. A cross-sectional survey of attending pediatric cardiologists who care for patients with FHD was performed. The respondents' demographics, fellowship experiences related to FHD counseling, reflections on fellowship training, and current practice habits were collected. The Fetal Heart Society endorsed this survey. There were 164 survey responses. 56% of respondents did not have 4th-year subspecialty training in fetal cardiology. Observing and performing FHD counseling were the most commonly used methods of training, with the highest perceived effectiveness. The number of counseling sessions observed and performed correlated moderately with confidence in FHD counseling skills at fellowship graduation. Extracardiac pathology and neurodevelopment were the least frequently addressed topics in fellowship training and in current practice. Fewer than 50% of respondents received formal education and feedback in counseling techniques during fellowship training. A significant proportion of practicing pediatric cardiologists provide FHD counseling with only standard categorical training. This highlights the potential importance of expanding FHD counseling education into categorical fellowship curricula. We suggest increasing opportunities for fellows to perform FHD counseling and receive feedback as this is a valued and beneficial experience during training. A formalized curriculum including extracardiac pathology and neurodevelopment and the use of evidence-based workshops in counseling techniques may address identified gaps in fellowship education.

Congenital Aortic-Left Atrial Tunnel with Coarctation and Anomalous Left Coronary Artery from the Pulmonary Artery: A First-of-its-kind Case Report.

Aortic-left atrial (Ao-LA) tunnel is an extremely rare vascular anomaly that involves an abnormal channel originating from the sinuses of the Valsalva and terminating in the left atrium. We present an unusual case of prenatally diagnosed Ao-LA tunnel with postnatal diagnosis of coarctation of the aorta and anomalous origin of the left coronary artery from the pulmonary artery (ALCAPA).

NAFTNet retrospective report on the treatment of anti-Ro/SSA mediated fetal heart block with dexamethasone.

BACKGROUND: Complete atrioventricular block (CAVB) is a complication of maternal antibody positivity and treatment of fetal disease is controversial in terms of efficacy and safety. We hypothesized that dexamethasone treatment for fetal anti-Ro/SSA antibody-mediated cardiac disease leads to better pregnancy outcomes than expectant management. METHODS: A retrospective multi-center cohort study of anti-Ro/SSA antibody positive pregnancies with fetal conduction disease reported by participating North American Fetal Therapy Network (NAFTNet) centers between January 2010 and December 2018. The primary outcomes included: fetal death, oligohydramnios, growth restriction, preterm delivery, and new maternal comorbidities. Secondary outcomes included: pacemaker prior to 28 days, transplantation, and neonatal death in maternal/fetal dyads treated with dexamethasone versus not. RESULTS: In 127 anti-Ro/SSA positive pregnancies, 98 were treated with dexamethasone and 29 were not. Of those treated, 61/96 (63.5%) met the primary outcome including 45/91 (49.4%) premature deliveries; 20 mothers developed comorbidities during treatment (fetal death 5, 10 growth restriction, 14 oligohydramnios, two new/worsening gestational diabetes). In the untreated group, 15/25 (60%) met the primary outcome including 11/22 (50%) premature deliveries and four mothers developing comorbidities during their pregnancy (fetal death 3, one growth restriction, one new onset maternal hypertension). Regarding secondary outcomes, 37/96 (43%) treated fetuses required a pacemaker or died by 28 days, while untreated 13/25 (52%) required pacemaker placement, died prior to 28 days or required listing for transplantation. Excluding terminations, survival without transplant was 17 (68%) in untreated and 85 (89%) in treated patients (p<.01). CONCLUSIONS: While the use of dexamethasone in anti-Ro/SSA positive pregnancies is associated with a high rate of poor pregnancy outcomes, there was an unexpected similarly high rate in untreated positive pregnancies. This suggests that the maternal disease itself is influencing pregnancy complications independent of dexamethasone. Our data, which show that treatment decreases neonatal morbidity and overall mortality without increasing overall pregnancy complications, warrant further study.

The aorto-left ventricular tunnel from a fetal perspective: Original case series and literature review.

INTRODUCTION: Aorto-left ventricular tunnel (ALVT) accounts for <0.1% of congenital heart defects. Evidence on the prognosis from a fetal perspective is limited. With this retrospective international case series, we provide information on the outcome of fetuses with ALVT. METHODS: All members of the Association for European Pediatric and Congenital Cardiology's (AEPC) fetal working group and fetal medicine units worldwide were invited for participation. We observed antenatal parameters, neonatal outcome and postnatal follow-up. Additionally, a systematic search of the literature was performed. RESULTS: Twenty fetuses with ALVT were identified in 10 participating centers (2001-2019). Fetal echocardiographic characteristics of ALVT included an increased cardiac-thorax ratio (95%), left ventricular end-diastolic diameter (90%) and a dysplastic aortic valve (90%). Extracardiac malformations were rare (5%). Eight fetuses died at a median gestational age (GA) of 21 + 6 weeks (range, 19-24): all showed signs of hydrops prior to 24 weeks or at autopsy. All others (60%, 12/2) were live-born (median GA 38 + 4, range 37-40), underwent surgery and were alive at last follow up (median 3.2 years, range 0.1-17). The literature reported 22 ALVT fetuses with similar outcome. CONCLUSIONS: In the absence of fetal hydrops, ALVT carries a good prognosis. Fetuses who survive to 24 weeks without hydrops are likely to have a good outcome.