Predicting High-Risk Fetal Cardiac Disease Anticipated to Need Immediate Postnatal Stabilization and Intervention with Planned Pediatric Cardiac Operating Room Delivery.

BACKGROUND: Distances between delivery and cardiac services can make the care of fetuses with cardiac disease at risk of acute cardiorespiratory instability at birth a challenge. In 2013 we implemented a fetal echocardiography-based algorithm targeting fetuses considered high risk for acute cardiorespiratory instability at ≤2 hours of birth for delivery in our pediatric cardiac operating room of our children's hospital, and, herein, examine our experience. METHODS AND RESULTS: We reviewed maternal and postnatal medical records of all fetuses with cardiac disease encountered January 2013 to March 2022 considered high risk for acute cardiorespiratory instability. Secondary analysis was performed including all fetuses with diagnoses of d-transposition of the great arteries/intact ventricular septum (d-TGA/IVS) and hypoplastic left heart syndrome (HLHS) encountered over the study period. Forty fetuses were considered high risk for acute cardiorespiratory instability: 15 with d-TGA/IVS and 7 with HLHS with restrictive atrial septum, 4 with absent pulmonary valve syndrome, 3 with obstructed anomalous pulmonary veins, 2 with severe Ebstein anomaly, 2 with thoracic/intracardiac tumors, and 7 others. Pediatric cardiac operating room delivery occurred for 33 but not for 7 (5 with d-TGA/IVS, 2 with HLHS with restrictive atrial septum). For high-risk cases, fetal echocardiography had a positive predictive value of 50% for intervention/extracorporeal membrane oxygenation/death at ≤2 hours and 70% at ≤24 hours. Of "low-risk" cases, 6/46 with d-TGA/IVS and 0/45 with HLHS required intervention at ≤2 hours. Fetal echocardiography for predicting intervention/extracorporeal membrane oxygenation/death at ≤2 hours had a sensitivity of 67%, specificity 93%, and positive and negative predictive values of 80% and 87%, respectively, for d-TGA/IVS, and 100%, 95%, 71%, and 100% for HLHS, respectively. CONCLUSIONS: Fetal echocardiography can predict the need for urgent intervention in a majority with d-TGA/IVS and HLHS and in half of the entire spectrum of high-risk cardiac disease.

Impact of Neonatal Intervention on Left Ventricular Performance in Ebstein's Anomaly and Tricuspid Valve Dysplasia.

BACKGROUND: Severe neonatal Ebstein's anomaly (EA) and tricuspid valve dysplasia (TVD) are associated with high perinatal morbidity and mortality. The authors recently demonstrated left ventricular (LV) dysfunction and dyssynchrony to be prevalent in affected newborns and to contribute to poor outcomes. The aim of this study was to investigate the impact of patent ductus arteriosus (PDA) closure, spontaneous or surgical ligation, or right ventricular exclusion (Starnes procedure) on LV performance in neonatal EA and TVD. METHODS: Neonates with EA or TVD encountered from 2004 to 2018 at three institutions were identified. Pre- and postoperative LV function was assessed using two-dimensional, Doppler-derived deformation (six-segment vector velocity imaging) and two measures of mechanical dyssynchrony (the SD of time to peak and global dyssynchrony index), and values were compared using paired t test analysis or the Wilcoxon rank sum test. RESULTS: Before the intervention, LV function was impaired in the PDA (n = 18) and Starnes (n = 6) groups and was similar between groups. After PDA closure, LV performance did not change. After the Starnes procedure, however, LV function, including synchrony, improved significantly: fractional area change from 45 ± 5% to 58 ± 8% (P = .003), global circumferential strain from -18.2 ± 5.0% to -32.5 ± 5.5% (P = .01), cardiac index from 1.9 ± 0.3 to 3.9 ± 1.5 L/min/m2 (P = .05), and circumferential strain dyssynchrony (dyssynchrony index from 0.19 ± 0.09 to 0.04 ± 0.02 [P = .009] and SD of time to peak from 59.8 ± 18.5 to 29.9 ± 8.2 [P = .02]). CONCLUSION: The Starnes procedure results in early improvements in LV dysfunction and dyssynchrony, not observed after PDA closure in neonatal severe EA and TVD, which may benefit critically unwell neonates.

Perinatal iron restriction is associated with changes in neonatal cardiac function and structure in a sex-dependent manner.

Iron deficiency (ID) is common during gestation and in early infancy and can alter developmental trajectories with lasting consequences on cardiovascular health. While the effects of ID and anemia on the mature heart are well documented, comparatively little is known about their effects and mechanisms on offspring cardiac development and function in the neonatal period. Female Sprague-Dawley rats were fed an iron-restricted or iron-replete diet before and during pregnancy. Cardiac function was assessed in a cohort of offspring on postnatal days (PD) 4, 14, and 28 by echocardiography; a separate cohort was euthanized for tissue collection and hearts underwent quantitative shotgun proteomic analysis. ID reduced body weight and increased relative heart weights at all time points assessed, despite recovering from anemia by PD28. Echocardiographic studies revealed unique functional impairments in ID male and female offspring, characterized by greater systolic dysfunction in the former and greater diastolic dysfunction in the latter. Proteomic analysis revealed down-regulation of structural components by ID, as well as enriched cellular responses to stress; in general, these effects were more pronounced in males. ID causes functional changes in the neonatal heart, which may reflect an inadequate or maladaptive compensation to anemia. This identifies systolic and diastolic dysfunction as comorbidities to perinatal ID anemia which may have important implications for both the short- and long-term cardiac health of newborn babies. Furthermore, therapies which improve cardiac output may mitigate the effects of ID on organ development.

Trends in the Prenatal Detection of Major Congenital Heart Disease in Alberta From 2008-2018.

OBJECTIVE: The effect of expanded obstetrical ultrasound cardiac views on the diagnosis of fetal congenital heart disease (CHD) has not been fully examined at a population level. We hypothesized there has been a significant increase in the prenatal detection of CHD in Alberta, particularly for CHD associated with cardiac outflow tract and 3-vessel view abnormalities. METHODS: Using provincial databases, we retrospectively identified all fetuses and infants diagnosed between 2008 and 2018 in Alberta with major CHD requiring surgical intervention within the first postnatal year. We evaluated individual lesions and categorized CHDs into the following groups based on the obstetrical ultrasound cardiac views required for detection: (1) 4-chamber view (e.g., hypoplastic left heart syndrome, Ebstein's anomaly, single ventricle); (2) outflow tract view (e.g., tetralogy of Fallot, d-transposition, truncus arteriosus); (3) 3-vessel or other non-standard cardiac views (e.g., coarctation, anomalous pulmonary veins); and (4) isolated ventricular septal defects using any view. RESULTS: Of 1405 cases of major CHD, 814 (58%) were prenatally diagnosed. Over the study period, prenatal detection increased in all groups, with the greatest increase observed for groups 1 and 2 (75%-88%; P = 0.008 and 56%-79%; P = 0.0002, respectively). Although rates of prenatal detection also increased for groups 3 and 4 (27%-43%; P = 0.007 and 13%-30%; P = 0.04, respectively), fewer than half of the cases in each group were detected prenatally, even in more recent years. CONCLUSIONS: While rates of prenatal detection of CHD have significantly improved during the past decade, many defects with abnormal 3-vessel and non-standard views, as well as isolated ventricular septal defects, still go undetected.

Left Ventricular Dysfunction in Neonatal Ebstein's Anomaly and Tricuspid Valve Dysplasia.

BACKGROUND: The mechanisms and prognostic importance of left ventricular (LV) dysfunction in neonatal Ebstein's anomaly (EA) and tricuspid valve dysplasia (TVD) are not well understood. The authors recently demonstrated reduced cardiac output and dyssynchrony to be common in fetal EA/TVD and therefore hypothesized that LV dysfunction may be associated with worse outcomes in neonatal EA/TVD. METHODS: A multicenter retrospective case-control study was conducted among neonatal patients with EA/TVD (n = 32) and a healthy control cohort (n = 17) encountered from 2004 to 2019. The left ventricle was assessed in the first 48 hours after birth using two-dimensional, Doppler-derived, six-segment global and segmental longitudinal strain and circumferential strain (CS) and dyssynchrony indices (the SD of time-to-peak strain and a novel global dyssynchrony index [DI], calculated as [peak segmental average - peak global average]/peak segmental average). RESULTS: Neonates with EA/TVD demonstrated reduced combined cardiac index (4.2 ± 1.5 L/min/m2 vs 6.5 ± 2.2 L/min/m2 in control subjects, P < .001), impaired LV CS (-15.4 ± 6.9 vs -26.2 ± 5.8, P < .001), and increased circumferential dyssynchrony (CS DI 0.20 ± 0.16 vs 0.09 ± 0.04 [P = .019]; SD of time-to-peak CS 63 ± 25 vs 40 ± 15 [P = .003]). Transplantation-free survival occurred in 20 of 32 patients (63%) at 6 months. Increased CS DI and absence of pulmonary valve flow (PVF) were most predictive of mortality; CS DI > 0.2 was associated with 25% survival in subjects without PVF, whereas all patients with CS DI < 0.1 survived. CONCLUSIONS: In neonates with EA/TVD and absence of PVF, there is abnormal LV deformation and compromised cardiac output in association with increased dyssynchrony. Increased CS DI is associated with increased risk for mortality in EA/TVD with no forward PVF.

The Perinatal Transition and Early Neonatal Period in Hypoplastic Left Heart Syndrome Is Associated With Reduced Systemic and Cerebral Perfusion.

BACKGROUND: The impact of the striking perinatal circulatory changes on blood flow distribution have not to date been well examined in hypoplastic left heart syndrome (HLHS). This study aimed to document perinatal redistribution of cardiac output in HLHS compared with healthy control subjects, to further understand the impact of the perinatal transition on cerebral and systemic blood flow. METHODS: Prospectively recruited HLHS case subjects (n = 31) and healthy control subjects (n = 19) underwent serial echocardiography from late fetal stages to 96 hours after birth. Combined cardiac output (CCO), systemic, pulmonary, cerebrovascular, and splanchnic flow data were compared between neonates with HLHS and control subjects, and the impact of vasoactive support and positive pressure ventilation in HLHS patients was examined. RESULTS: In late gestation, CCO was similar between HLHS and control subjects, whereas middle cerebral artery (MCA) pulsatility index (PI) in HLHS was consistent with low cerebral vascular resistance. In the 96 hours after birth, CCO and pulmonary blood flow progressively increased in HLHS compared with control subjects (P < 0.001), and CCO was further increased in neonates with HLHS receiving vasoactive support (P = 0.01). Neonates with HLHS had reduced systemic and 6-24-hour superior vena cava (SVC) flow compared with control subjects (P < 0.001). Low systemic flow was further suggested by increased MCA and celiac artery PI at 6-48 hours in neonates with HLHS (P < 0.001). Systemic and SVC flow did not differ between those with and without vasoactive support. CONCLUSIONS: We provide quantitative echocardiographic evidence associating impaired cerebral and systemic blood flow with perinatal hemodynamic changes in the preoperative neonate with HLHS.

Quantitative Assessment of Left Ventricular Dysfunction in Fetal Ebstein's Anomaly and Tricuspid Valve Dysplasia.

BACKGROUND: Fetal Ebstein's anomaly and tricuspid valve dysplasia (EA/TVD) are associated with high perinatal mortality relative to pulmonary atresia with intact ventricular septum (PAIVS), despite both requiring redistribution of the cardiac output (CO) to the left ventricle (LV). LV dysfunction is suspected to contribute to adverse outcomes in EA/TVD. OBJECTIVE: We sought to examine global and segmental LV function in fetal EA/TVD with comparison to normal controls and PAIVS. We hypothesized that LV dysfunction in EA/TVD is associated with abnormal LV remodeling and interventricular mechanics. METHODS: We retrospectively identified 63 cases of fetal EA/TVD (40 with retrograde ductal flow) and 22 cases of PAIVS encountered from 2004 to 2015 and compared findings to 77 controls of comparable gestational age. We measured the combined CO and global LV function using two-dimensional, Doppler-derived, deformational (six-segmental vector velocity imaging) and dyssynchrony indices (DIs; SD of time to peak), and a novel global DI. RESULTS: EA/TVD fetuses demonstrated abnormal LV global systolic function with reduced ejection fraction, fractional area change, and CO, while in PAIVS we observed a normal ejection fraction, fractional area change, and CO. PAIVS, but not EA/TVD, demonstrated increased LV sphericity, suggestive of remodeling, and associated enhanced radial function in the third trimester. In contrast, while EA/TVD fetuses had normal LV segmental longitudinal strain, there was abnormal radial segmental deformation and LV dyssynchrony with increased SD of time to peak and DI. CONCLUSIONS: Fetal EA/TVD is associated with a lack of spherical remodeling and presence of mechanical dyssynchrony, which likely contribute to reduced CO and ejection fraction. Clinical monitoring of LV function is warranted in fetal EA/TVD. Further studies incorporating quantification of LV function into prediction models for adverse outcomes are required.

Exercise-induced hypoxia secondary to an atrial septal defect and cor triatriatum dexter.

A 14-year-old boy presented to us with a diagnosis of severe asthma and oxygen desaturation of 76% on a 6-minute-walk test. A contrast echocardiogram revealed echocontrast in the left and right atria simultaneously. A secundum atrial septal defect and partial cor triatriatum dexter were diagnosed, and the atrial defect was closed by cardiac catheterisation.