Fetal Hemodynamics, Early Survival, and Neurodevelopment in Patients With Cyanotic Congenital Heart Disease.

BACKGROUND: Fetuses with cyanotic congenital heart disease (CHD) exhibit profound fetal circulatory disturbances that may affect early outcomes. OBJECTIVES: This study sought to investigate the relationship between fetal hemodynamics and early survival and neurodevelopmental (ND) outcomes in patients with cyanotic CHD. METHODS: In this longitudinal observational study, fetuses with cyanotic CHD underwent late gestational fetal cardiovascular magnetic resonance (CMR) to measure vessel blood flow and oxygen content. Superior vena cava (SVC) flow was used as a proxy for cerebral blood flow. Primary outcomes were 18-month mortality and Bayley Scales of Infant Development-III assessment. RESULTS: A total of 144 fetuses with cyanotic CHD were assessed. By 18 months, 18 patients (12.5%) died. Early mortality was associated with reduced combined ventricular output (P = 0.01), descending aortic flow (P = 0.04), and umbilical vein flow (P = 0.03). Of the surviving patients, 71 had ND outcomes assessed. Cerebral oxygen delivery was the fetal hemodynamic variable most strongly associated with cognitive, language, and motor outcomes (P < 0.05). Fetal SVC flow was also associated with cognitive, language, and motor outcomes (P < 0.01), and it remained an independent predictor of cognitive (P = 0.002) and language (P = 0.04) outcomes after adjusting for diagnosis. Diminished SVC flow also performed better than other fetal CMR and echocardiographic predictors of cognitive ND delay (receiver-operating characteristic curve area: 0.85; SE 0.05). CONCLUSIONS: Among fetuses with cyanotic CHD, diminished fetal combined ventricular output is associated with mortality, whereas cerebral blood flow and oxygen delivery are associated with early cognitive, language, and motor development at 18 months of age. These results support the inclusion of fetal CMR to help identify patients at risk of adverse ND outcomes.

Pharmacological Management of Cardiac Arrhythmias in the Fetal and Neonatal Periods: A Scientific Statement From the American Heart Association: Endorsed by the Pediatric & Congenital Electrophysiology Society (PACES).

Disorders of the cardiac rhythm may occur in both the fetus and neonate. Because of the immature myocardium, the hemodynamic consequences of either bradyarrhythmias or tachyarrhythmias may be far more significant than in mature physiological states. Treatment options are limited in the fetus and neonate because of limited vascular access, patient size, and the significant risk/benefit ratio of any intervention. In addition, exposure of the fetus or neonate to either persistent arrhythmias or antiarrhythmic medications may have yet-to-be-determined long-term developmental consequences. This scientific statement discusses the mechanism of arrhythmias, pharmacological treatment options, and distinct aspects of pharmacokinetics for the fetus and neonate. From the available current data, subjects of apparent consistency/consensus are presented, as well as future directions for research in terms of aspects of care for which evidence has not been established.

Decreased left heart flow in fetal lambs causes left heart hypoplasia and pro-fibrotic tissue remodeling.

Low blood flow through the fetal left heart is often conjectured as an etiology for hypoplastic left heart syndrome (HLHS). To investigate if a decrease in left heart flow results in growth failure, we generate left ventricular inflow obstruction (LVIO) in mid-gestation fetal lambs by implanting coils in their left atrium using an ultrasound-guided percutaneous technique. Significant LVIO recapitulates important clinical features of HLHS: decreased antegrade aortic valve flow, compensatory retrograde perfusion of the brain and ascending aorta (AAo) from the arterial duct, severe left heart hypoplasia, a non-apex forming LV, and a thickened endocardial layer. The hypoplastic AAo have miRNA-gene pairs annotating to cell proliferation that are inversely differentially expressed by bulk RNA-seq. Single-nucleus RNA-seq of the hypoplastic LV myocardium shows an increase in fibroblasts with a reciprocal decrease in cardiomyocyte nuclei proportions. Fibroblasts, cardiomyocytes and endothelial cells from hypoplastic myocardium have increased expression of extracellular matrix component or fibrosis genes with dysregulated fibroblast growth factor signaling. Hence, a severe sustained ( ~ 1/3 gestation) reduction in fetal left heart flow is sufficient to cause left heart hypoplasia. This is accompanied by changes in cellular composition and gene expression consistent with a pro-fibrotic environment and aberrant induction of mesenchymal programs.

High-sensitivity cardiac troponin T in infants exposed to anti-Ro antibodies.

OBJECTIVES: Cardiac involvement in neonatal lupus erythematosis (NLE) can present as myocarditis/endocardial fibroelastosis (EFE). It is unknown whether high-sensitivity cardiac troponin T (hs-cTnT) is useful in identifying subclinical myocardial inflammation in infants exposed prenatally to anti-Ro antibodies. This study reports hs-cTnT levels in infants exposed to anti-Ro antibodies with/without cardiac NLE and reports cardiac MRI (CMR) findings in a subset of these children. METHODS: The study included 45 consecutive infants exposed prenatally to anti-Ro antibodies with (n = 7) or without (n = 38) cardiac NLE, who were seen at the SickKids NLE Clinic between 2012 and 2014. Hs-cTnT levels were measured at least once, and those infants with values of ≥30 ng/l were offered the opportunity to undergo CMR. Descriptive statistics were performed. RESULTS: Of 38 infants without cardiac NLE, 25 had a hs-cTnT level of ≥30 ng/l (including 1 of >113 ng/l); of these, 8 underwent CMR (all without myocarditis/EFE). All 7 infants with cardiac NLE had at least one hs-cTnT level of ≥30 ng/l, but only 2/7 had a level of >113 ng/l; 4/7 infants with cardiac NLE had CMR (all without myocarditis/EFE); 6/7 infants with cardiac NLE had their steroid treatment adjusted based on the trend in their hs-cTnT levels. CONCLUSION: Only 3/45 anti-Ro antibodies-exposed infants had hs-cTnT values outside the reference range reported in healthy infants. None of 12 infants who had CMR had subclinical myocarditis/EFE. Routine measurement of hs-cTnT in every anti-Ro antibody-exposed infant is not indicated. Further studies are needed to define the role of hs-cTnT as a biomarker for cardiac NLE.

Maternal Anti-Ro Antibody Titers Obtained With Commercially Available Immunoassays Are Strongly Associated With Immune-Mediated Fetal Heart Disease.

OBJECTIVE: Anti-Ro antibody-positive mothers are frequently referred for serial echocardiography due to the fetal risk of developing heart block and endocardial fibroelastosis. Little is known why only some and not all offspring develop these cardiac manifestations of neonatal lupus (CNL). This prospective study examined associations between anti-Ro antibody titers and fetal CNL. METHODS: Antibody-positive mothers referred since 2018 for fetal echocardiography at risk of CNL (group 1; n = 240) or with CNL (group 2; n = 18) were included. Maternal antibody titers were measured with a chemiluminescent immunoassay (CIA). Additional testing on diluted serum samples was used to quantify anti-Ro 60 antibody titers above the analytical measuring range (AMR) of the standard CIA (≥1,375 chemiluminescent units [CU]). RESULTS: Among 27 total mothers with a fetal diagnosis of CNL, all displayed anti-Ro 60 antibody titers that exceeded the AMR of the CIA at least 10-fold. Of 122 mothers in group 1 who underwent additional anti-Ro 60 antibody testing, event rates of CNL (n = 9) were 0% (0 of 45) among mothers with anti-Ro 60 antibody titers from 1,375-10,000 CU, 5% (3 of 56) among mothers with titers from 10,000-50,000 CU, but 29% (6 of 21) among mothers with titers >50,000 CU (odds ratio 13.1, P = 0.0008). Of mothers in group 2 with a primary diagnosis of CNL, 0% (0 of 18 mothers) had anti-Ro 60 antibody titers <10,000 CU, 44% (8 of 18 mothers) had titers from 10,000-50,000 CU, and 56% (10 of 18 mothers) had titers >50,000 CU. CONCLUSION: CNL is associated with substantially higher anti-Ro antibody titers than are obtained using a standard CIA. Enhancing the assay measuring range allows an improved specificity of identifying pregnancies at risk of CNL.

Atrial Standstill in the Pediatric Population: A Multi-Institution Collaboration.

BACKGROUND: Atrial standstill (AS) is a rare condition characterized by absence of electrical activity within the atria. Studies to date have been limited. OBJECTIVES: The authors sought to describe the clinical characteristics, genetics, and outcomes of patients with AS. METHODS: This was a retrospective multicenter study of patients <18 years at AS diagnosis, defined as absence of atrial activity documented during an electrophysiology study, device placement, or noninvasive rhythm tracings and confirmed by echocardiogram. Patients with acquired disorders were excluded. Clinical details and genetic variants were recorded and analyzed. RESULTS: Twenty patients were diagnosed at a median age of 6.6 years (IQR: 2.9-10.8 years). Arrhythmias included 16 (80%) with atrial/supraventricular arrhythmias and 8 (40%) with ventricular tachycardia, including 4 with cardiac arrests. A type 1 Brugada pattern was documented in 4. Pacemakers were implanted in 18 (90%). Although atrial leads were attempted in 15, only 4 achieved pacing at implantation. During a median follow-up of 6.9 years (IQR: 1.2-13.3 years), 7 (35%) had thromboembolic events. Of these, none had atrial pacing, 6 were not on anticoagulation, and 1 was on aspirin. Genetic testing identified SCN5A variants in 13 patients (65%). Analyses suggest SCN5A loss-of-function may be one mechanism driving AS. Ventricular arrhythmias and cardiac arrest were more commonly seen in patients with biallelic SCN5A variants. CONCLUSIONS: AS may be associated with loss-of-function SCN5A variants. Patients demonstrate atrial and ventricular arrhythmias, and may present challenges during device placement. Patients without the capacity for atrial pacing are at risk for thromboembolic events and warrant anticoagulation.

Comparison of Pre- and Postnatally Diagnosed Coronary Artery Fistulae: Echocardiographic Features and Clinical Outcomes.

BACKGROUND: Coronary artery fistulae (CAFs) are abnormal connections of a coronary artery to a cardiac chamber or vessel. There is a paucity of data regarding clinical outcomes, especially when detected prenatally. METHODS: This was a multicenter retrospective cohort study of all CAF cases from 2002 to 2016. Clinical characteristics and outcomes were compared between the prenatal and postnatal cohorts. A scoping literature review of prenatal CAFs was completed. RESULTS: CAFs were diagnosed prenatally in 12 (median, 23 weeks' gestation; interquartile range, 17-36 weeks' gestation) and postnatally in 94 (median, 2.8 years; interquartile range, 0-15 years) cases. Structural heart defects were present in five (42%) prenatal and 19 (20%) postnatal cases (P = .011) and genetic conditions in five (42%) and 14 (15%), respectively (P = .001). CAFs were considered large in 12 (100%) prenatal versus 14 (15%) postnatal cases (P < .001). The CAF distribution was similar between cohorts: 39 (67%) from the left and 19 (33%) from the right coronary artery, with the most common exit sites being the main pulmonary artery 54 (51%), right ventricle 30 (28%), and right atrium 12 (11%). Of prenatal cases, all large at presentation, none progressed, six (50%) resolved by birth, and one (8%) underwent elective neonatal ligation. Of postnatal cases, one presented in cardiogenic shock, and no other case had ventricular dysfunction, arrhythmias, or ischemic changes. Nine (10%) with large shunts underwent intervention (seven percutaneous, two surgical), of whom three were symptomatic. Two (17%) prenatal and two (2%) postnatal cases had coronary abnormalities, two with normal results on stress perfusion imaging. Postnatal death occurred in two (17%) prenatal and four (4%) postnatal cases (P = .05). Of the total 36 prenatal cases reported in the literature, including the 12 cases in the present series, 10 (28%) had clinical symptoms at birth, including three (8%) with cardiogenic shock, and 19 (53%) underwent intervention. CONCLUSIONS: Prenatally and postnatally encountered CAFs are associated with a good prognosis for most, with many not requiring intervention. Although half of the prenatal CAFs resolved prenatally, given the risk for cardiogenic shock at birth and heart failure in early infancy, appropriate perinatal planning and postnatal surveillance is warranted.

Impact of Planned Delivery on the Perinatal Outcome of Term Fetuses with Isolated Heart Defects.

OBJECTIVE: Pregnancies complicated by fetal heart defects often undergo a planned delivery prior to term by either induction of labour or cesarean delivery to ensure optimal availability of neonatal care. We aimed to assess whether such planned deliveries achieve their goal of better perinatal care. METHODS: We conducted a retrospective case-control study of pregnancies complicated by isolated fetal cardiac defects, without other fetal comorbidities, managed at a single fetal medicine unit over a 10-year period. Only pregnancies delivered past 37 weeks gestation were included. Patients undergoing elective delivery for care planning reasons only were compared with patients in whom planned delivery was clinically indicated and patients who laboured spontaneously. Obstetric and perinatal outcomes were recorded. RESULTS: Of the 180 pregnancies included in the study, 59 (32.8%) were in the elective group, 49 (27.2%), in the indicated group, and 72 (40%), in the spontaneous group. Mean gestational age at delivery was 39.0 ± 1.1 weeks overall and did not differ between the groups. For the elective group, only 35.6% of deliveries occurred during office hours, which was similar to the 2 other groups. The rate of adverse obstetric or postnatal outcomes was not statistically significantly different between groups. CONCLUSION: Timed delivery at term does not seem to be associated with an increased risk of poor perinatal outcomes. It may improve perinatal care by providing proximity to a neonatal intensive care unit and convenience for patients and providers.

Postnatal recurrence and transesophageal inducibility of prenatally treated fetal supraventricular tachycardia.

BACKGROUND: Antiarrhythmic treatment of fetal supraventricular tachycardia (SVT) is used to prevent morbidity and mortality. The postnatal management of survivors is often arbitrary and varied. OBJECTIVE: The purpose of this study was to examine the utility of a risk-based postnatal management strategy. METHODS: Sixty-six prenatally treated newborns with fetal long or short ventriculoatrial tachycardia were reviewed. Postnatal diagnoses included atrioventricular reentrant tachycardia, atrial ectopic tachycardia, and permanent junctional reciprocating tachycardia. Unless SVT persisted to birth, early neonatal observation without treatment was recommended. For newborns without spontaneous arrhythmia after ≥2 days of observation, inducibility was tested by transesophageal pacing study (TEPS). Postnatal therapy was advised for spontaneous or inducible SVT. Characteristics associated with these outcomes were analyzed. RESULTS: Twenty-eight patients (42%) experienced SVT at or early after birth, which was associated with fetal long ventriculoatrial tachycardia (odds ratio [OR] 6.8; 95% confidence interval [CI] 1.88-24.57; P = .0029); delayed in utero cardioversion with treatment (median 11 days vs 5.5 days; P < .0001); prenatal treatment with multiple antiarrhythmics (OR 4.42; 95% CI 1.56-12.55; P = .0059); and postnatal atrial ectopic tachycardia/permanent junctional reciprocating (OR 18.0; 95% CI 2.11-153.9; P = .0013). Of the 38 neonates undergoing TEPS, 19 (50%) had inducible tachyarrhythmias. Recurrence of SVT during infancy or childhood was documented in 4 of 6 patients with SVT at birth (66%), 8 of 22 patients with early neonatal SVT (36%), 4 of 19 patients with inducible SVT (21%), and 0 of 19 untreated patients without inducible SVT (0%) (P = .0032). CONCLUSION: The postnatal risk of SVT is related to the arrhythmia mechanism and prenatal treatment response. In newborns without spontaneous SVT, TEPS may be useful to guide the need for postnatal treatment on the basis of SVT inducibility.

Impact of fetal haemodynamics on surgical and neurodevelopmental outcomes in patients with Ebstein anomaly and tricuspid valve dysplasia.

OBJECTIVES: To evaluate the impact of fetal haemodynamics on surgical and neurodevelopmental outcomes in severe Ebstein anomaly and tricuspid valve dysplasia. METHODS: Thirty-four fetuses with Ebstein anomaly/tricuspid valve dysplasia were referred from 2013 to 2019 for fetal echocardiography and clinical management. Nineteen fetuses with Ebstein anomaly/tricuspid valve dysplasia and 30 controls underwent cardiovascular magnetic resonance to quantify the fetal blood flow and to calculate cerebral oxygen delivery (cDO2) and consumption (cVO2). The 3D steady-state free precession acquisition was used to measure fetal brain volume. Surgical outcome, brain MRI, and neurodevelopmental follow-up were reviewed. RESULTS: Twenty-six fetuses were live born (76%) and survival (65%) at a mean follow-up of 4 years. Nine fetuses had a brain MRI before discharge, and all had clinically silent injuries and volume loss. At 18 months, five single-ventricle patients had a neurodevelopmental delay in cognition and language (mean percentile: 11th), with gross-motor skills more affected than fine-motor skills (mean percentiles: 4th and 34th). Fetuses with Ebstein anomaly/tricuspid valve dysplasia had smaller brains, lower combined ventricular output, ascending aorta, superior caval vien and umbilical vein flows, lower oxygen saturation in ascending aorta and superior caval vien, lower cDO2 and cVO2 (p < 0.05). Superior caval vien/combined ventricular output and descending aorta/combined ventricular output ratios were lower in fetuses with circular shunt (p < 0.05). Fetuses requiring the Starnes procedure tended to have smaller brains, lower combined ventricular output, superior caval vien, descending aorta, and umbilical vein flows. CONCLUSIONS: All patients with Ebstein anomaly/tricuspid valve dysplasia are at high risk of neurodevelopmental delay and warrant follow-up. Fetal cardiovascular magnetic resonance revealed impaired brain growth with diminished cerebral blood flow and cDO2, the extenting dependent on the severity of the haemodynamic compromise.

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.

Outcome of Antibody-Mediated Fetal Heart Disease With Standardized Anti-Inflammatory Transplacental Treatment.

Background Transplacental fetal treatment of immune-mediated fetal heart disease, including third-degree atrioventricular block (AVB III) and endocardial fibroelastosis, is controversial. Methods and Results To study the impact of routine transplacental fetal treatment, we reviewed 130 consecutive cases, including 108 with AVB III and 22 with other diagnoses (first-degree/second-degree atrioventricular block [n=10]; isolated endocardial fibroelastosis [n=9]; atrial bradycardia [n=3]). Dexamethasone was started at a median of 22.4 gestational weeks. Additional treatment for AVB III included the use of a ß-agonist (n=47) and intravenous immune globulin (n=34). Fetal, neonatal, and 1-year survival rates with AVB III were 95%, 93%, and 89%, respectively. Variables present at diagnosis that were associated with perinatal death included an atrial rate <90 beats per minute (odds ratio [OR], 258.4; 95% CI, 11.5-5798.9; P<0.001), endocardial fibroelastosis (OR, 28.9; 95% CI, 1.6-521.7; P<0.001), fetal hydrops (OR, 25.5; 95% CI, 4.4-145.3; P<0.001), ventricular dysfunction (OR, 7.6; 95% CI, 1.5-39.4; P=0.03), and a ventricular rate <45 beats per minute (OR, 12.9; 95% CI, 1.75-95.8; P=0.034). At a median follow-up of 5.9 years, 85 of 100 neonatal survivors were paced, and 1 required a heart transplant for dilated cardiomyopathy. Cotreatment with intravenous immune globulin was used in 16 of 22 fetuses with diagnoses other than AVB III. Neonatal and 1-year survival rates of this cohort were 100% and 95%, respectively. At a median age of 3.1 years, 5 of 21 children were paced, and all had normal ventricular function. Conclusions Our findings reveal a low risk of perinatal mortality and postnatal cardiomyopathy in fetuses that received transplacental dexamethasone±other treatment from the time of a new diagnosis of immune-mediated heart disease.

Prenatal Diagnosis of Vascular Ring: Evaluation of Fetal Diagnosis and Postnatal Outcomes.

BACKGROUND: The impact of fetal echocardiography on the diagnosis and outcomes of vascular ring has not been well examined. We hypothesized that prenatal detection of vascular ring has improved over time and that prenatal diagnosis of vascular ring is associated with earlier intervention and favorable outcomes. METHODS: This is a single-center, retrospective study of the evolution and outcomes of prenatal diagnosis of vascular ring from 2000 to 2020. We compared clinical presentation, timing of surgical intervention, and outcomes between the prenatally and postnatally diagnosed cases during the same study period. RESULTS: A total of 170 patients were included: 50 with prenatal and 120 with postnatal diagnosis of vascular ring. Prenatal diagnoses included 42 patients (84%) with right aortic arch (RAA), aberrant left subclavian artery (ALSCA), and a left-sided ductus arteriosus and eight (16%) patients with double aortic arch (DAA). The postnatal cohort consisted mainly of 90 patients (75%) with DAA and 22 (18%) with RAA-ALSCA. None of the postnatally diagnosed cases had undergone a fetal echocardiogram. Numbers (percentage) of prenatally diagnosed cases of vascular ring compared with the postnatal cases improved from 4/31 (13%), to 10/29 (34%), to 14/25 (56%), and to 22/35 (69%), respectively, during 2000-2005, 2005-10, 2010-15, and 2015-20 (P = .032). Vascular ring was an isolated abnormality in 84% and 85% of the prenatal and postnatal cohorts, respectively. Compared with the prenatal cohort, postnatally diagnosed patients with an isolated vascular ring were more frequently symptomatic (66% vs 48%, P < .03) and underwent cross-sectional imaging (69% vs 44%, P = .009) and surgery more frequently (79% vs 48%, P = .003). Surgery was performed at a later patient age (18 [2-147] months vs 4.8 [0.5-42] months, P = .01) and was more often associated with residual symptoms (27/81 [33%] vs 1/20 [5%], P = .01) in the postnatal cohort than in the prenatal cohort. CONCLUSIONS: The diagnosis of vascular ring by fetal echocardiography has improved over time. A significantly higher incidence of RAA-ALSCA in the prenatal compared with the postnatal cohort suggests that patients with this form of vascular ring often do not present to medical attention with significant symptoms postnatally. Prenatal diagnosis of vascular ring was associated with a lower incidence of symptoms, less frequent use of cross-sectional imaging, earlier age at surgical intervention, and lower likelihood of residual symptoms.

Ethnicity and Neonatal Lupus Erythematosus Manifestations Risk in a Large Multiethnic Cohort.

OBJECTIVE: To evaluate the association between ethnicity and neonatal lupus erythematosus (NLE), as well as specific NLE manifestations in a large multiethnic population. METHODS: We conducted a cohort study of the children (≤ 1 yr of age) seen in the NLE clinic at The Hospital for Sick Children (SickKids), between January 2011 and April 2019. The cohort was divided into European, non-European, and mixed European-non-European groups according to parent-reported child's ethnicity (Canada Census categories). Outcomes were NLE and specific NLE manifestations (cardiac, cutaneous, cytopenias, transaminitis, and macrocephaly). The frequency of NLE and specific manifestations were compared between ethnic groups (Fisher exact test). We tested the association between ethnicity and (1) NLE risk, and (2) specific NLE manifestations with logistic regression models, including covariates for child's sex, maternal rheumatic disease status during pregnancy, and maternal use of antimalarials during pregnancy (multiple comparisons threshold P < 0.008). RESULTS: We included 324 children born to 270 anti-Ro antibody-positive mothers. Median age at first visit was 1.8 (IQR 1.4-2.3) months, and median follow-up time was 12 (IQR 2-24) months. The majority was non-European (48%), with 34% European, and 18% mixed European-non-European. There was no significant association between non-European ethnicity (OR 1.18, 95% CI 0.71-1.94, P = 0.51), mixed European-non-European ethnicity (OR 1.13, 95% CI 0.59-2.16, P = 0.70), and NLE risk compared with European ethnicity. We also did not find an association between ethnicity and specific NLE manifestations in univariate or multivariable-adjusted models. CONCLUSION: In a large multiethnic cohort, there was no association between a child's ethnicity and NLE risk or specific NLE manifestations.

Effects of Transplacental Dexamethasone Therapy on Fetal Immune-Mediated Complete Heart Block.

INTRODUCTION: Antibody-mediated complete atrioventricular block (CAVB) is considered irreversible. We sought to examine the effects of transplacental steroids on fetal AV conduction. METHODS: Fifty-nine fetuses diagnosed with CAVB at our center from 1996 to 2018 were reviewed. Routine dexamethasone administration to birth was used to limit cardiac inflammatory damage. Restoration of fetal AV conduction was classified as "unexpected" treatment response. RESULTS: CAVB resolved in 5/29 (17%) fetuses first treated ≤24-week gestation with 8 mg/day of dexamethasone, when compared with 0/30 (0%) when treatment was initiated later and/or at a starting dose of 4 mg/day (odds ratio 13.69; 95% confidence interval 0.72-260.13; p = 0.024). Treatment response was also associated with a faster ventricular rate at diagnosis (median [range]: 80 [60-97] beats per minute [bpm] vs. 58 [38-92] bpm; p = 0.0036). CAVB reappeared in all 5 responders either prenatally (n = 1) or postnatally before (n = 3) or after (n = 1) the first year of life. When compared with infants with treatment-resistant CAVB (median follow-up 10.3 years), responders (median follow-up 12.3 years) required postnatal pacing less frequent (2/5 [40%] vs. 45/49 [92%]; p = 0.013). CONCLUSIONS: In a subgroup of CAVB fetuses, dexamethasone transiently restored AV conduction. This was associated with a lower rate of postnatal pacing when compared with nonresponders.

Extracardiac Doppler indices predict perinatal mortality in fetuses with Ebstein anomaly and tricuspid valve dysplasia.

OBJECTIVES: Ebstein anomaly and tricuspid valve dysplasia (EA/TVD) carry high perinatal mortality. Past studies have focused on cardiac predictors of mortality; we sought to describe the fetal echo (FE) extracardiac Dopplers in this cohort and determine their association with perinatal mortality. METHOD: Fetuses with EA/TVD at 23 centers from 2005-2011 were included for retrospective study. Doppler pattern and velocity of the umbilical artery (UA), umbilical vein (UV), ductus venosus (DV), and middle cerebral artery (MCA) were collected. Bivariate and multivariate analyzes were performed. The primary outcome measure was perinatal mortality, defined as fetal demise or neonatal death. RESULTS: Of 190 cases that met eligibility criteria, alterations were seen in 50% of UA, 16% of UV, 48% of DV, and 8% of MCA Doppler indices on the last FE (median 27.4 weeks). Independent predictors of perinatal mortality included abnormal UA Doppler pattern of absence or reversed end diastolic flow (OR 9.7) and UV velocity z score <1 (OR 2.5), in addition to diagnosis <32 weeks (OR 4.2) and tricuspid valve (TV) annulus z score ≥6 (OR 5.3). CONCLUSION: Abnormal UA Doppler pattern and decreased UV velocity are independent predictors of perinatal mortality in EA/TVD fetuses and should be used to refine mortality risk and guide perinatal management.

Umbilical and Middle Cerebral Artery Doppler Measurements in Fetuses With Congenital Heart Block.

OBJECTIVES: In fetal congenital complete heart block, the slow fetal heart rate prolongs the diastolic phase of the cardiac cycle, which may affect Doppler measurements that are typically used to quantify placental function. We here describe the umbilical artery (UA) and middle cerebral artery (MCA) Dopplers in a cohort of fetuses with heart block, hypothesizing that values will be increased but nevertheless remain associated with placental function and fetal outcome. METHODS: We retrospectively reviewed Doppler measurements of the UA and MCA pulsatility index (PI) and resistance index in fetuses with complete heart block. The cerebroplacental ratio (CPR) was calculated as a marker of central redistribution. Measurements were transformed to Z scores and compared between fetuses born with a normal weight (appropriate for gestational age [AGA]) to those with fetal growth restriction (FGR) and correlated with a composite adverse outcome consisting of FGR, fetal death, or preterm birth prior to 34 weeks' gestation. RESULTS: Fifty-four fetuses were included. There were 36 (67%) live births, 8 (22%) stillbirths, and 10 (19%) pregnancy terminations. Of those born alive, 14 (39%) had FGR. The UA PI decreased with gestational age and was higher in FGR compared with AGA fetuses (P < .001). Twenty-three percent of AGA fetuses developed absent end-diastolic flow in the UA. The MCA PI did not change with gestation and did not differ between AGA and FGR fetuses. The CPR was lower in FGR than in AGA fetuses (-2.43 ± 0.85 vs -1.44 ± 1.04, P = .006). The UA PI and resistance index were strongly correlated with the composite adverse outcome (P < .001). CONCLUSIONS: The UA and MCA PI are significantly elevated in fetuses with complete heart block. The UA Doppler indices and CPR nevertheless still reflect placental function. Longitudinal measurements may be useful in monitoring well-being in fetuses with heart block.