Use of a Postoperative Care Management Pathway Reduces the Incidence of Chylothorax Post-Fontan Palliation.

Pleural effusions and chylothorax are challenging morbidities post-Fontan palliation. We sought to evaluate the efficacy of our Fontan Care Pathway (FCP) in reducing the incidence of post-operative chylothorax and Time to Chest Tube Removal (TTCTR), and to determine risk factors associated with longer TTCTR. Between 2016 and 2022 our institutional approach to post-Fontan care fell into three categories: Group 1 (n = 36): no standardized approach; Group 2 (n = 30): a prophylactic chylothorax diet (fat content < 5%); Group 3 (n = 57): the FCP (a chylothorax diet, fluid restriction, supplemental O2 and aggressive diuresis). The incidence of chylothorax and TTCTR was compared between groups. Predictors of TTCTR were analyzed using linear regression modelling, adjusting for covariates. Chylothorax rate decreased in Group 3 compared to Groups 1 and 2 (9% vs. 28% and 33% respectively, p = 0.011), without alteration in TTCTR. Univariate factors associated with median TTCTR included chylothorax (+ 13.7 days, p = 0.001), additional procedures at time of Fontan (+ 2.4 days per procedure p = 0.017), Fontan revision or takedown (+ 11.7 days, p = 0.018) and minor/major complications (+ 5.1, p = 0.01 and + 15.8, p < 0.001, respectively). On multivariable analysis, chylothorax (+ 6.5 days, p = 0.005) and major complications (+ 15.8 days, p = 0.001) were associated with increased TTCTR. When chylothorax was excluded from multivariable analysis, the FCP showed a significant decrease in TTCTR (- 3.3 days, p = 0.034). A bundled therapy approach was associated with reduced laboratory confirmed chylothorax post-Fontan, whereas diet change alone was not. Additional studies in this area, with larger sample sizes are warranted.

Lower Socioeconomic Status is Associated with an Increased Incidence and Spectrum of Major Congenital Heart Disease and Associated Extracardiac Pathology.

Several studies have suggested an inverse relationship between lower socioeconomic status (SES) and the incidence of congenital heart disease (CHD) among live births. We sought to examine this relationship further in a Canada-wide population study, exploring CHD subtypes, trends, and associated noncardiac abnormalities. Infants born in Canada (less Quebec) from 2008 to 2018 with CHD requiring intervention in the first year were identified using ICD-10 codes through the Canadian Institute for Health Information Discharge Abstract Database. Births of CHD patients were stratified by SES (census-based income quintiles) and compared against national birth proportions using X2 tests. Proportions with extracardiac defects (ED) and nonlethal genetic syndromes (GS) were also explored. From 2008 to 2018, 7711 infants born with CHD were included. The proportions of major CHD distributed across SES quintiles were 27.1%, 20.1%, 19.2%, 18.6%, and 15.0% from lowest to highest, with significant differences relative to national birth proportions (22.0%, 20.0%, 20.6%, 20.7%, and 16.7% from lowest (1) to highest (5)) (p < 0.0001). No temporal trends in the CHD proportions across SES categories were observed over the study period. The distribution across SES quintiles was different only for specific CHD subtypes (double-outlet right ventricle (n = 485, p = 0.03), hypoplastic left heart syndrome (n = 547, p = 0.006), heterotaxy (n = 224, p = 0.03), tetralogy of Fallot (n = 1007, p = 0.008), truncus arteriosus (n = 126, p < 0.0001), and ventricular septal defect (n = 1916, p < 0.0001)), with highest proportions observed in the lowest quintile. The proportion of the total population with ED but not GS was highest in lower SES quintiles (< 0.0001) commensurate with increased proportion of CHD. Our study suggests a negative association between SES and certain CHD lesions and ED.

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.

Extra-cardiac diagnoses and postnatal outcomes of fetal tetralogy of fallot.

OBJECTIVE: Past studies of fetal tetralogy of fallot (ToF) have reported extra-cardiac anomalies (ECAs) in 17%-45%, genetic syndromes in as low as 20% and poor postnatal outcomes. This study sought to examine these factors in a contemporary cohort. METHODS: A retrospective review examining 83 fetuses with ToF diagnosed 2012-2019. Referral indication, ToF subtype, additional cardiac, extra-cardiac and genetic diagnoses, pregnancy outcomes and survival were documented. RESULTS: The mean gestational age at diagnosis was 23 ± 4 weeks. Of 94% (78/83) with genetic testing (GT), 30% (23/78, 95%CI 21%-40%) had genetic anomalies (GA), including Trisomy 21 (39%, 9/23), 22q11 deletion (35%, 8/23), Trisomy 13 or 18 (17%, 4/23) and 9% (2/23) others. A further 4% (3/78) had VACTERL association. Forty-one percent (34/83, 95%CI 31%-52%) had ≥1 major ECA of whom 41% (14/34) also had a genetic anomaly. OUTCOMES: 22% (18/83) pregnancy termination, 5% (4/83) intrauterine death and 72% (60/83) live birth. Of live births, 3% (2/60) experienced neonatal death, 7% late death (4/60) and 90% (54/60) were alive at last follow-up (mean age 3.5 ± 2.4 years). CONCLUSION: In a cohort of fetuses with ToF and high rates of GT, compared to previous reports, GA were more common and there were similar rates of ECAs.

Comparing a knowledge-based 3D reconstruction algorithm to TomTec 3D echocardiogram algorithm in measuring left cardiac chamber volumes in the pediatric population.

BACKGROUND: Three-dimensional echocardiography (3DE) is an emerging method for volumetric cardiac measurements; however, few vendor-neutral analysis packages exist. Ventripoint Medical System Plus (VMS3.0+) proprietary software utilizes a validated Magnetic resonance imaging (MRI) database of normal ventricular and atrial morphologies to calculate chamber volumes. This study aimed to compare left ventricular (LV) and atrial (LA) volumes obtained using VMS3.0+ to Tomtec echocardiography analysis software. METHODS: Healthy controls (n = 98) aged 0-18 years were prospectively recruited and 3D DICOM datasets focused on the LV and LA acquired. LV and LA volumes and ejection fractions were measured using TomTec Image Arena 3D LV analysis package and using VMS3.0+. Pearson correlation coefficients, Bland-Altman's plots, and intraclass coefficients (ICC) were calculated, along with analysis time. RESULTS: There was a very good correlation between Ventripoint Medical System (VMS) and Tomtec LV systolic (r2  = .88, ICC .89 [95% CI .81, .94]), and diastolic (r2  = .88, ICC .90 [95% CI .77, .95]) volumes, and between VMS and Tomtec LA diastolic (r2  = .75, ICC .89 [95% CI .81, .93]) and systolic (r2  = .88, ICC .91 [95% CI .78, .96]) volumes on linear regression models. Natural log transformations eliminated heteroscedasticity, and power transformations provided the best fit. The time (mins) to analyze volumes using VMS were less than using Tomtec (LV VMS 2.3 ± .5, Tomtec 3.3 ± .8, p < .001; LA: VMS 1.9 ± .4, Tomtec 3.4 ± 1.0, p < .001). CONCLUSIONS: There was a very good correlation between knowledge-based (VMS3.0+) and 3D (Tomtec) algorithms when measuring 3D echocardiography-derived LA and LV volumes in pediatric patients. VMS was slightly faster than Tomtec in analyzing volumetric measurements.

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.

Fetal double outlet right ventricle without heterotaxy syndrome: Diagnostic spectrum, associated extracardiac pathology and clinical outcomes.

OBJECTIVES: To document the clinical spectrum and outcomes of fetal double outlet right ventricle (DORV) without heterotaxy in a recent diagnostic era. METHODS: Prenatal cases of DORV consecutively diagnosed from 2007 to 2018 were retrospectively identified. Clinical records, including details regarding genetic testing and pre and postnatal imaging were reviewed. RESULTS: DORV was diagnosed in 99 fetuses without heterotaxy. The most common anatomic subtype was subaortic ventricular septal defect (VSD) and normally related great arteries with (n = 45, 45%) or without (n = 13, 13%) pulmonary stenosis. The remainder had a subpulmonic VSD with transposed great arteries (n = 15, 15%), atrioventricular valve atresia (n = 24, 24%), or remote VSD (n = 2, 2%). A genetic diagnosis was found in 32 (34%) of 93 tested. Major extracardiac anomalies were found in 40 (40%), including 17/24 (71%) with and 22/69 (32%) without an abnormal karyotype, with VACTERL association in 9. Genetic and/or extracardiac pathology was identified in 37/58 (64%) with a subaortic VSD, 5/15 (33%) with a subpulmonic VSD, 9/24 (38%) of those with AV valve atresia and 2/2 (100%) with a remote VSD. A genetic abnormality was a significant predictor of fetal demise (9/37 vs 1/62 p < 0.01) or pregnancy termination (12/35 vs 9/64 p = 0.03). CONCLUSIONS: Fetal DORV is associated with a high rate of genetic abnormalities and extracardiac pathology. The presence of genetic abnormalities impacts prenatal outcomes and parental decision-making.

Influence of extreme prematurity and bronchopulmonary dysplasia on cardiac function.

OBJECTIVE: Prematurity and bronchopulmonary dysplasia (BPD) are associated with poorly understood abnormalities of ventricular function. We therefore comprehensively compared biventricular function in infants with and without BPD. METHODS: Prospective observational study in extremely preterm infants with (n = 20) and without (n = 38) BPD using conventional and advanced echocardiography at 28 days (T1) and near-term (T2). RESULTS: Infants with BPD had lower birth gestational age (26.7±1.9 vs 27.4±1.1 weeks, p = 0.047) and weight (884±207 vs 1108±190 g, p = 0.0001). BPD was associated with larger right ventricles (RV) and reduced RV systolic strain rate at T1 and pulmonary hypertensive indicators at T2 (pulmonary artery acceleration time BPD 51±17 vs no BPD 63±12 ms, p = 0.017). At T1/T2, infants with BPD had lower RV tissue Doppler velocities (e', a' and s) and higher E/e' ratios (T1: BPD 10.4±2.4 vs no BPD 6.2±3.1 cm/sec, p = 0.001; T2: BPD 8.0±3.1 vs no BPD 5.6±2.6 cm/sec, p = 0.02), altered LV diastolic function (apical circumferential T1 early diastolic strain rate BPD 2.8±0.8 vs no BPD 3.6±1.0 /sec, p = 0.04; T2 late diastolic strain rate, BPD 2.29 ± 0.99 vs no BPD 1.67±0.84 /sec, p = 0.03) and LV rotational mechanics (T1: twist rate BPD 90±16 vs no BPD 130±48 deg/sec, p = 0.008; untwist rate (UTR) BPD -69±90 vs no BPD -147±68 deg/sec, p = 0.008; torsion BPD 2.78±0.56 vs no BPD 4.48±1.74 deg/cm, p = 0.009; and T2: UTR BPD -132±69 vs no BPD -179±57 deg/sec, p = 0.013). CONCLUSION: BPD is associated with altered RV diastolic function that persists near term, with elevated pulmonary vascular resistance, and with persistent alterations in LV apical strain rate and rotational mechanics.

Fetal Diagnosis is Associated with Improved Perioperative Condition of Neonates Requiring Surgical Intervention for Coarctation.

To define the relative importance of fetal diagnosis and comorbidities in severity of preoperative compromise, outcomes and hospitalization in neonatal coarctation of the aorta (CoA). Retrospective comparison of preoperative condition and postoperative course of neonates prenatally (PreDx n = 48) or postnatally diagnosed (PostDx n = 67) with CoA. Congenital and non-congenital comorbidities were adjusted for. Postnatal diagnosis was associated with preoperative mortality (n = 2), and severe acidosis (lactate > 5 mM or pH < 7.20) on multivariate analysis (OR 4.2 (1.3-14.4, p = 0.02), with extracardiac congenital anomalies also a risk factor (OR 3.2 (1.03-10, p = 0.044). Median age at operation was delayed in the PostDx group (PreDx 6.5 days (IQR 4-9) vs PostDx 10 days (IQR 6-17)). Only comorbid left heart disease and extracardiac congenital anomalies were associated with prolonged total length of hospital stay. Prenatal diagnosis is the major adjustable risk factor affecting preoperative condition in critical CoA but does not reduce length of stay.

Right Ventricular Remodeling in Hypoplastic Left Heart Syndrome is Minimally Impacted by Cardiopulmonary Bypass: A Comparison of Norwood vs. Hybrid.

Right ventricular (RV) remodeling in hypoplastic left heart syndrome (HLHS) begins prenatally and continues through staged palliations. However, it is unclear if the most marked observed remodeling post-Norwood is secondary to cardiopulmonary bypass (CPB) exposure or if it is an adaptation intrinsic to the systemic RV. This study aims to determine the impact of CPB on RV remodeling in HLHS. Echocardiograms of HLHS survivors undergoing stage 1 Norwood (n = 26) or Hybrid (n = 20) were analyzed at pre- and post-stage 1, pre- and post-bidirectional cavo-pulmonary anastomosis (BCPA), and pre-Fontan. RV fractional area change (FAC), vector velocity imaging for longitudinal & derived circumferential deformation (global radial shortening (GRS) = peak radial displacement/end-diastolic diameter), and deformation ratio (longitudinal/ circumferential) were assessed. Both groups had similar age, clinical status and functional parameters pre-stage 1. No difference in RV size and sphericity at any stage between groups. RVFAC was normal (> 35%) throughout for both groups. Both Norwood and Hybrid patients had increased GRS (p = 0.0001) post-stage 1 and corresponding unchanged longitudinal strain, resulting in decreased deformation ratio (greater relative RV circumferential contraction), p = 0.0001. Deformation ratio remained decreased in both groups in subsequent stages. Irrespective of timing of the first CPB exposure, both Norwood and Hybrid patients underwent similar RV remodeling, with relative increase in circumferential to longitudinal contraction soon after stage 1 palliation. The observed RV remodeling in HLHS survivors were minimally impacted by CPB.

Cardiac function and dysfunction in the fetus.

Evaluation of fetal cardiac function is one of the most important components of fetal echocardiography. Fetal cardiac dysfunction is closely linked to risk of intrauterine fetal demise, in many, but not all cases is indicative of worse postnatal prognosis and may prompt the use of medications or interventions to optimize outcomes. There may be implications for termination versus continuation of pregnancy, an indication for early delivery, a change in location and even mode of delivery. In extreme cases, fetal cardiac dysfunction may prompt prenatal or early neonatal listing for cardiac transplantation. There are several important differences between the fetal and postnatal circulatory physiology which affect echocardiographic assessment of cardiac dysfunction. In this review, we examine the echocardiographic findings according to their underlying pathophysiology with reference to common causes.

Flail anterior tricuspid valve leaflet in a neonate: association with maternal antiphospholipid syndrome.

This brief report describes a case of flail anterior tricuspid valve leaflet in a neonate associated with maternal antiphospholipid syndrome. Fetal echocardiography at 27 weeks of gestation showed competent atrioventricular valves with biventricular echogenic chordae. Fetal distress was noted at delivery, and echocardiography showed a flail anterior leaflet of the tricuspid valve with severe regurgitation. Possible causation and implications of maternal antiphospholipid syndrome are discussed.

Twenty-five-year survival for aboriginal and caucasian children with congenital heart defects in Western Australia, 1980 to 2010.

BACKGROUND: Australian Aboriginal children have increased infant and childhood mortality compared with Caucasian children, but their mortality related to congenital heart defects (CHDs) throughout life is unknown. METHODS: We conducted a retrospective cohort study using data on 8,110 live born, singleton infants with CHDs born January 1980 to December 2010 from the Western Australian Register of Developmental Anomalies. Vital status was determined from death and medical records. Data for infants with chromosomal anomalies (except Down syndrome) were excluded. Kaplan-Meier Product-Limit estimates and 95% confidence intervals (CIs) were computed by Aboriginality. Hazard ratios (HRs) and 95% CIs were calculated from multivariable Cox-Proportional Hazard Regression models. RESULTS: Aboriginal children had lower survival than Caucasians for all CHDs combined but most notably during the neonatal period for functional single ventricle (50.0% vs. 86.1%; p = 0.015) and during the postneonatal period for tetralogy of Fallot (87.0% vs. 97.4%; p = 0.021) and atrioventricular septal defect (60.0% vs. 94.6%; p = 0.010). After adjusting for covariates except remoteness and socioeconomic status (SES), Aboriginal children with all CHDs combined (HR = 1.4; 95% CI, 1.0-1.9), with transposition of the great arteries (HR = 4.3; 95% CI, 1.0-18.9) or functional single ventricle (HR = 8.6; 95% CI, 1.3-57.9) had increased risk of mortality compared with Caucasian children. When remoteness and SES were included, the risks were not statistically significant. CONCLUSION: Long-term survival was lower for Aboriginal children with CHDs, and Aboriginal children with specific CHD phenotypes had increased risk of mortality throughout life. Increased risk may be due to SES and environmental factors. Birth Defects Research (Part A), 2016. © 2016 Wiley Periodicals, Inc. Birth Defects Research (Part A) 106:1016-1031, 2016. © 2016 Wiley Periodicals, Inc.

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.

Two cases of warfarin-induced tracheobronchial calcification after Fontan surgery.

This study identified tracheobronchial cartilage calcification in children with congenital heart disease. Calcification of the tracheobronchial airways has been found previously in adults receiving warfarin and in children receiving warfarin after mitral valve replacement. A 9-year-old girl who had received a Fontan repair 6 years previously underwent a cardiac computed tomography (CT) scan to evaluate pulmonary artery size. The result was an incidental finding of extensive tracheobronchial cartilage calcification. A retrospective review of all pediatric Fontan patients who had undergone cardiac CT was conducted to search for calcification of the tracheobronchial cartilage. The study investigated ten pediatric Fontan patients who had undergone cardiac CT scanning. Two patients with extensive calcification of the tracheobronchial airways were identified. The index case had hypoplastic left heart syndrome, and the patient had undergone a staged repair with the Fontan at the age of 3 years. A 16-year-old boy with tricuspid atresia had undergone staged repair and Fontan at the age of 3.5 years. These two patients had received continuous warfarin therapy for 6 and 13 years, respectively. Other common causes of airway calcification were excluded from the study. This report describes warfarin-induced tracheobronchial calcification in patients after the Fontan procedure. This finding has possible implications for airway growth and vascular calcification.

Socioeconomic Determinants of Health: Remoteness From Care.

Remoteness from care remains a major challenge to equitable provision of health services worldwide. Beyond the difficulties associated with geographically and climatically rugged terrain, there are also socioeconomic, cultural, and technological challenges associated with remote residence. The objective of this review is to examine the factors whereby remoteness can be associated with sociodemographic disadvantage in health care and describe some of the methodologies for measurement and analysis of remoteness, with examples from the literature, particularly focusing on Canada. As surrogates for remoteness, simple measurements of direct distance or travel time may correlate well with more complex measures and can be performed relative to specific health care services of interest (for example, tertiary obstetric service). These metrics may also be measured, as general proxies for service availability, to various sizes of population centres. More complex measures of remoteness may also incorporate modes of available transport and availability of specific services into an index such as the Canadian Index of Remoteness. As an important independent predictor of health, remoteness requires careful predictive modelling because of potential complex nonlinear relationships, edge effects created by health system zone boundaries, and covariance with other sociodemographic factors and Indigenous population proportions. To combat disadvantage caused by remoteness, innovation in health service delivery, policy, and technology is required. Health-resource allocation must be adequate, and innovative technological advances-such as remote monitoring, expert clinical support, and artificial intelligence algorithms-must be supported by development of appropriate technological infrastructure, targeting remote regions. With these, the barriers to equitable health imposed by remoteness can be overcome.

A Comparison of Perinatal Circulatory Transition in Critical Right and Left Heart Obstructive Lesions.

BACKGROUND: During perinatal transition in hypoplastic left heart syndrome (HLHS) reduced systemic (Qs) and cerebral blood flow and increased pulmonary flow (Qp) is observed, contributing to hemodynamic instability. In the current study, we explored whether similar or discordant perinatal changes occur in critical pulmonary outflow obstruction (POFO), when compared to HLHS and healthy controls. METHODS: Echocardiography was prospectively performed at 36-39 gestational weeks and then serially from 6-96 hours after birth prior to cardiac intervention. The combined cardiac output (CCO) superior vena cava (SVC), Qs and Qp flow-rates, and resistance indices (RI) in middle cerebral artery (MCA), celiac and superior mesenteric arterial were compared between the three groups. RESULTS: In fetal POFO (n=19) and HLHS (n=31), CCO was comparable to controls (n=21) due to elevated stroke volume, but CCO in POFO was lower compared to HLHS (p<0.01). Compared to controls, POFO CCO was lower at 6 hours post-delivery, but comparable at 24-96 hours. In contrast, from 6-96 hours the HLHS group had higher CCO than POFO and controls. Compared to controls, both POFO and HLHS neonates had lower Qs and SVC flow (POFO 24 hours (p<0.001), HLHS 6-hour Qs and 6-24-hour SVC flow). Compared to controls, Qp was increased in POFO at 48-96 hours (p< 0.05) and in HLHS at all time points (P<0.001). Compared to fetal MCARI, postnatal MCARI was acutely higher in both POFO and HLHS, whereas, in controls, it tended to decrease postnatally. Celiac artery RI and superior mesenteric artery pulsatility index were higher in POFO and HLHS from 6 to 48 hours versus controls. CONCLUSION: POFO and HLHS demonstrate divergent acute hemodynamic changes in the early neonatal period with early decreased CCO in POFO and increased CCO in HLHS. Both demonstrate early compromise in Qs and SVC (cerebral flow) and ongoing altered splanchnic flow.

PERINATAL CARDIAC FUNCTIONAL ADAPTATION IN HYPOPLASTIC LEFT HEART SYNDROME: A LONGITUDINAL ANALYSIS.

BACKGROUND: The perinatal transition is characterized by acute changes in cardiac loading. Compared to normal newborn combined cardiac output (CCO), single right ventricular (RV) output of neonates with hypoplastic left heart syndrome (HLHS) is markedly greater. We sought to examine the mechanisms of cardiac adaptation which facilitate this perinatal transition from late fetal to early neonatal life in HLHS. METHODS: Prospectively recruited pregnancies complicated by fetal HLHS (n=35) and health controls (Ctrl, n=17) underwent serial echocardiography in late gestation (38±1weeks) and 6, 24 and 48 hours after birth. Cardiac function was assessed using conventional, tissue Doppler and speckle tracking echocardiography. RESULTS: Term HLHS fetuses had an RV output (RVCO) comparable to Ctrl CCO via higher stroke volume (SV). Compared to both left ventricular (LV) and RV indices of Ctrls, they exhibited a globular and dilated RV with reduced relative wall thickness (RWT) [RWT: 0.40±0.08 vs. 0.49±0.10, p<0.01], increased Tei index' [HLHS vs. Ctrl LV/Ctrl RV: sphericity index (SI): 0.9±0.25 vs. 0.5±0.10/0.6±0.11, RV area index: 28±6cm2/m2 vs. 15±3cm2/m2/17±5cm2/m2, Tei index': 0.65±0.11 vs. 0.43±0.07/0.45±0.09, all p<0.0001]. HLHS neonates generated elevated RVCO compared to Ctrl CCO via higher heart rate and SV, with further RV dilatation, increased longitudinal systolic strain at 48h [-17±4% vs. -14±3%/-14±5%] with reduced circumferential and rotational myocardial deformation and altered diastolic function. HLHS neonates also demonstrated right atrial (RA) enlargement with increased longitudinal strain: 6h (33±12% vs. 26±6%), 24h (37±15% vs. 26±13%), 48h (38±11% vs. 24±13%), p<0.0001. CONCLUSIONS: Term HLHS fetuses exhibit altered RV geometry and RV systolic and diastolic functional parameters. After birth, further alterations in these cardiac parameters likely reflect adaptation to acutely altered RV loading from increasing cardiac output and pulmonary artery flow demands.

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.