Right Heart Structure, Geometry and Function Assessed by Echocardiography in 6-Year-Old Children Born Extremely Preterm-A Population-Based Cohort Study.

Preterm birth has been associated with altered cardiac phenotype in adults. Our aim was to test the hypothesis that children surviving extremely preterm birth have important structural or functional changes of the right heart or pulmonary circulation. We also examined relations between birth size, gestational age, neonatal diagnoses of bronchopulmonary dysplasia (BPD) and patent ductus arteriosus (PDA) with cardiac outcomes. We assessed a population-based cohort of children born in Sweden before 27 weeks of gestation with echocardiography at 6.5 years of age (n = 176). Each preterm child was matched to a healthy control child born at term. Children born preterm had significantly smaller right atria, right ventricles with smaller widths, higher relative wall thickness and higher estimated pulmonary vascular resistance (PVR) than controls. In preterm children, PVR and right ventricular myocardial performance index (RVmpi') were significantly higher in those with a PDA as neonates than in those without PDA, but no such associations were found with BPD. In conclusion, children born extremely preterm exhibit higher estimated PVR, altered right heart structure and function compared with children born at term.

Cardiac Troponin T in Healthy Full-Term Infants.

In this prospective cohort study of healthy full-term infants, we hypothesized that high-sensitivity cardiac troponin T (hs-cTnT) would be elevated in cord blood, compared with adult reference values, and that it would further increase over the first days of age. Cardiac troponin T has been shown to be significantly increased in healthy full-term newborns compared with adult reference values, but there is no established reference range. Most studies of cTnT in newborns have been performed before the introduction of high-sensitivity cTnT (hs-cTnT) assay. We conducted a study including 158 full-term newborns, at Stockholm South General Hospital. High-sensitivity cTnT was analyzed in umbilical cord blood and at 2-5 days of age. Median hs-cTnT (interquartile range) in cord blood was 34(26-44) ng/L; 99th percentile 88 ng/L. Median hs-cTnT at 2-5 days of age was 92(54-158) ng/L; 99th percentile 664 ng/L. We conclude that hs-cTnT is elevated in cord blood in healthy, full-term newborn infants compared with adult reference values, and that it increases significantly during the first days of life. Our findings further underline the need of caution when using hs-cTnT as a measurement of cardiac impact in newborns.

A rapid smartphone-based lactate dehydrogenase test for neonatal diagnostics at the point of care.

There is a growing recognition of the importance of point-of-care tests (POCTs) for detecting critical neonatal illnesses to reduce the mortality rate in newborns, especially in low-income countries, which account for 98 percent of reported neonatal deaths. Lactate dehydrogenase (LDH) is a marker of cellular damage as a result of hypoxia-ischemia in affected organs. Here, we describe and test a POC LDH test direct from whole blood to provide early indication of serious illness in the neonate. The sample-in-result-out POC platform is specifically designed to meet the needs at resource-limited settings. Plasma is separated from whole blood on filter paper with dried-down reagents for colorimetric reaction, combined with software for analysis using a smartphone. The method was clinically tested in newborns in two different settings. In a clinical cohort of newborns of Stockholm (n = 62) and Hanoi (n = 26), the value of R using Pearson's correlation test was 0.91 (p < 0.01) and the R2 = 0.83 between the two methods. The mean LDH (±SD) for the reference method vs. the POC-LDH was 551 (±280) U/L and 552 (±249) U/L respectively, indicating the clinical value of LDH values measured in minutes with the POC was comparable with standardized laboratory analyses.

The Preterm Heart in Childhood: Left Ventricular Structure, Geometry, and Function Assessed by Echocardiography in 6-Year-Old Survivors of Periviable Births.

BACKGROUND: Preterm birth has been associated with increased risk of cardiovascular morbidity in adult life. We evaluated whether preterm birth is associated with deviating cardiac structure and function before school start. METHODS AND RESULTS: In total, 176 children aged 6 years and born extremely preterm (EXPT; gestational age of 22-26 weeks) and 134 children born at term (control [CTRL]) were studied. We used echocardiography to assess left heart dimensions, geometry, and functions. Recording and off-line analyses of echocardiographic images were performed by operators blinded to group belonging. Body size, blood pressure, and heart rate were also measured. Rates of family history of cardiovascular disease and sex distribution were similar in the EXPT and CTRL groups. Heart rate and systolic blood pressure did not differ, whereas diastolic blood pressure was slightly higher in EXPT than CTRL participants. After adjusting for body surface area, left ventricular length, width, and aortic valve annulus diameter were 3% to 5% smaller in EXPT than CTRL participants. Left ventricular longitudinal shortening and systolic tissue velocity were 7% to 11% lower, and transversal shortening fraction was 6% higher in EXPT than CTRL participants. The EXPT group also exhibited lower atrial emptying velocities than the CTRL group. Sex, fetal growth restriction, or a patent ductus arteriosus in the neonatal period did not contribute to cardiac dimensions or performance. CONCLUSIONS: Six-year-old children born extremely preterm exhibit a unique cardiac phenotype characterized by smaller left ventricles with altered systolic and diastolic functions than same-aged children born at term.

Relationship between various maternal conditions and lactic acid dehydrogenase activity in umbilical cord blood at birth.

BACKGROUND: Lactic acid dehydrogenase (LDH) is a valuable marker for some of the most important diseases in newborns and the plasma LDH activity in newborns correlates well with conditions such as asphyxia. If LDH should be considered as a useful tool also in obstetric care, key factors associated with maternal health before and during pregnancy which could affect umbilical cord LDH activity need to be known. The aims of this study were to explore relationships between selected maternal conditions and arterial lactic acid dehydrogenase activity (aLDH) in umbilical cord blood at delivery. METHODS: A prospective observational study was conducted at Sodersjukhuset, Stockholm, Sweden. Included in the study were 1247 deliveries, and cord blood samples from each were analyzed for aLDH. Background, delivery and neonatal data were collected from the medical records. RESULTS: Higher median values of aLDH were found (P=0.001) among women with chronic disorders not related to pregnancy but there was no increased frequency of high aLDH levels (>612 µ/L, P=0.30). No difference in aLDH was identified between infants born to women with pregnancy-related disorders compared with healthy women, neither in median values, nor in high values (>612 µ/L, P=0.95). CONCLUSION: Newborn infants born to women with non-pregnancy-related chronic disorders had a somewhat higher median value of aLDH in cord blood at delivery. The influence of common maternal conditions and diseases on umbilical cord arterial LDH levels is small compared to the increase reported in fetal distress and several other critical conditions in the newborn.

Trends in Congenital Heart Defects in Infants With Down Syndrome.

BACKGROUND: As a result of antenatal screening, abortion of fetuses with Down syndrome has become increasingly common. Little is known about the cardiovascular phenotype in infants with Down syndrome born today. METHODS: Population-based cohort study based on national health registers including 2588 infants with Down syndrome, live-born in Sweden from 1992 to 2012. Risk ratios for congenital heart defects were calculated per 3-year period, adjusted for maternal age, parity, BMI, smoking, diabetes and hypertensive disease, and infant gender. RESULTS: Any congenital heart defect was diagnosed in 54% of infants with Down syndrome. Overall, year of birth was not associated with risk of any congenital heart defect. However, the risk of complex congenital heart defects decreased over time. Compared with 1992 to 1994, the risk in 2010 to 2012 was reduced by almost 40% (adjusted risk ratio 0.62, 95% confidence interval 0.48-0.79). In contrast, risks for isolated ventricular septal defect (VSD) or atrial septal defect showed significant increases during latter years. Overall, the 3 most common diagnoses were atrioventricular septal defect, VSD, or atrial septal defect, accounting for 42%, 22%, and 16% of congenital heart defects, respectively. Although atrioventricular septal defect was far more common than VSD in 1992 to 1994, they were equally common in 2010 to 2012. CONCLUSIONS: Complex congenital heart defects have become less common in infants diagnosed with Down syndrome. This phenotypic shift could be a result of selective abortion of fetuses with Down syndrome, or due to general improvements in antenatal diagnostics of complex congenital heart defects.

Childhood cardiac outcome after intrauterine laser treatment of twin-twin transfusion syndrome is favourable.

AIM: Intrauterine laser treatment is used to alleviate abnormal circulatory load and cardiac morbidity affecting foetuses with twin-twin transfusion syndrome (TTTS). We conducted this childhood follow-up study to fill the gap in knowledge about final cardiac outcomes after such interventions. METHODS: We investigated 19 TTTS pairs - 11 male and eight female - with a mean age of four and a half years (range 1.1-9.9) using 2D, blood flow and tissue Doppler, 3D and speckle tracking echocardiography, and compared them with 19 age-matched and gender-matched singletons. RESULTS: The only observed differences in cardiac structure or function between the donors and recipients were related to diastolic ventricular filling. Recipients had a lower left ventricular ratio of early and late diastolic filling compared with their donor cotwins [1.48(0.35) versus 1.66 (0.28), p < 0.05], but not compared with singleton controls. All observations, except one, were within the reference limits. Speckle tracking could not demonstrate any group differences in systolic ventricular function, besides marginally lower ventricular strain in the donors than controls. CONCLUSION: Double survivors of laser-treated TTTS showed only minor within-pair differences in diastolic cardiac function at childhood follow-up. Cardiac function in TTTS twins compared well to singleton controls, suggesting a favourable long-term outcome.

Survival and neonatal outcome after fetoscopic guided laser occlusion (FLOC) of twin-to-twin transfusion syndrome (TTTS) in Sweden.

AIM: To determine infant survival and neonatal outcome after fetoscopic laser treatment of twin-to-twin transfusion syndrome (TTTS). RESULTS: In 53/71(75%) laser-treated TTTS cases, at least one twin was liveborn and in 42/71(59%) cases at least one twin survived infancy. Fetal survival did not differ between donors [41/71(58%)] and recipients [46/71(65%), P=0.36]. Among liveborns, infant survival was 29/41(71%) in donors and 36/46(78%) in recipients (P=0.12). Infant survival did not correlate to maternal characteristics (age, BMI, smoking or parity), gestational age at treatment or severity of TTTS (Quintero stage). No TTTS infant born before 25 weeks of gestation survived the first week. Among the 87 infant survivors, 26 (30%) had an Apgar score <7 at 5 min, 47 (54%) developed respiratory distress syndrome, 10 (11%) showed signs of severe brain damage, nine (10%) renal failure, eight (9%) bronchopulmonary dysplasia, and five (6%) infants developed retinopathy of prematurity ≥stage 3. There was no significant difference in neonatal morbidity between recipients and donors. CONCLUSIONS: Fetal survival after laser treatment was comparable to that reported by other international centers. There was no significant difference in survival or neonatal morbidity between donors and recipients. Major neonatal morbidity was common, and combined with extremely preterm delivery the prognosis of TTTS is poor.