Long-Term Enlargement of the Neo-Aortic Root and Aortic Arch Following Arch Reconstruction in Hypoplastic Left Heart Syndrome.

BACKGROUND: Long-term enlargement of the aortic arch after aortic arch reconstruction (AAR) in hypoplastic left heart syndrome (HLHS) is not well described. METHODS: Aortic arch measurements for 50 patients with HLHS who achieved Fontan completion were converted to Pediatric Heart Network z-scores. Dimensions were assessed using linear mixed models and differences among time points were evaluated with F-tests. Sub-analysis was conducted comparing Norwood (n=36) vs hybrid (n=14) strategies. RESULTS: Median time to last imaging was 6.4 (IQR, 3.5-11.3) years. Prior to intervention, the main pulmonary artery was dilated whereas the ascending aorta (AA), transverse arch (TA), and isthmus (ISTH) were hypoplastic. With AAR, there were expected increases in all arch z-scores. The aortic arch continued to dilate after AAR reaching peak values at 7 months [Neo-Aortic Complex (NAC): z= 6.9 (5.6-8.0)] or 12 months following stage I [AAo: z=6.1 (2.9-8.3); TA: z=4.7 (3.0-5.9)]. Following peak values, there was a gradual decline in z-scores with most components still at least mildly dilated at 16 years [NAC: z=3.2 (3.1-3.9), AAo: z=3.9 (3.3-4.2); TA: z=3.1 (2.5-3.7)] with abrupt calibre change at ISTH: z= -0.8 (-1.1- -0.3)]. Norwood and hybrid strategies showed similar enlargement profiles after 7 months of age. CONCLUSIONS: Neo-aortic root and aortic arch in HLHS are enlarged early after AAR and continue to enlarge out of proportion to normal controls until 12 months of age, with gradual decline in enlargement up to adolescence. Further work should focus on modifiable surgical factors which may prove important to optimize arch growth and geometry.

Extracorporeal Membrane Oxygenation After Norwood Surgery in Patients With Hypoplastic Left Heart Syndrome: A Retrospective Single-Center Cohort Study From Brazil.

Background: Extracorporeal membrane oxygenation (ECMO) is increasingly being used to support patients after the repair of congenital heart disease. Objective: We report our experience with patients with a single functional ventricle who were supported by ECMO after the Norwood procedure, reviewing the outcomes and identifying risk factors for mortality in these patients. Methods: In this single-center retrospective cohort study, we enrolled 33 patients with hypoplastic left heart syndrome (HLHS) who received ECMO support after the Norwood procedure between January 2015 and December 2019. The independent variables evaluated in this study were demographic, anatomical, and those directly related to ECMO support (ECMO indication, local of initiation, time under support, and urinary output while on ECMO). The dependent variable was survival. A p < 0.05 was considered statistically significant. Results: The ECMO support was applied in 33 patients in a group of 120 patients submitted to Norwood procedure (28%). Aortic atresia was present in 72.7% of patients and mitral atresia in 51.5%. For 15% of patients, ECMO was initiated in the operating room; for all other patients, ECMO was initiated in the intensive care unit. The indications for ECMO in the cardiac intensive care unit were cardiac arrest in 22 (79%) of patients, low cardiac output state in 10 (18%), and arrhythmia in 1 patient (3%). The median time under support was 5 (2-25) days. The median follow-up time was 59 (4-150) days. Global survival to Norwood procedure was 90.9% during the 30-day follow-up, being 33.3% for those submitted to ECMO. Longer ECMO support (p = 0.004) was associated with a higher risk of death in the group submitted to ECMO. Conclusions: The mortality of patients with HLHS who received ECMO support after stage 1 palliation was high. Patients with low urine output were related to worse survival rates, and longer periods under ECMO support (more than 9 days of ECMO) were associated with 100% mortality. Earlier ECMO initiation before multiorgan damage may improve results.

Growth and Nutritional Intake of Infants with Univentricular Circulation.

OBJECTIVES: To evaluate the nutritional status and early nutritional intake of infants with univentricular congenital heart disease. STUDY DESIGN: The included infants underwent a Norwood procedure or hybrid intervention (stage 1) within the first 6 weeks of life, between January 2014 and January 2019, at Children's Health Ireland at Crumlin. Demographic, anthropometric, nutritional intake, and morbidity data were collected. RESULTS: Data were collected on 90 infants and 1886 neonatal admission days. There was a significant drop in mean weight-for-age z-score (WAZ) between measurements at birth, -0.01 and on discharge post stage 1 surgery -1.45 (P < .01). On hospital discharge (median hospital stay, 25 days) 32% of infants had a WAZ <-2 and 11% had a WAZ <-3. Pre-stage 1, 26% received trophic feeds and 39% received parenteral nutrition. Basal metabolic requirements and target caloric intake (120 kcal/kg) were met on 56% and 13% of admission days, respectively. Infants referred to a dietitian had a shorter time to any form of nutrition support, enteral feeds, and target caloric intake (P < .001, P = .016, and P = .048, respectively). At stage 3 (Fontan) surgery, 15% of infants were classified as stunted (length-for-age z-score [LAZ] <-2). CONCLUSIONS: The greatest decline in nutritional status occurs in the neonatal period, followed by significant growth stunting by the time of the Fontan procedure. Early involvement of dietitians is critical in the care of this nutritionally fragile group. With the currently low rate of preoperative nutritional support, there may be opportunities to improve intake at this critical stage.

Surgical Interventions in Infants Born Preterm with Congenital Heart Defects: An Analysis of the Kids' Inpatient Database.

OBJECTIVE: To evaluate short-term outcomes in infants born preterm with congenital heart defects (CHDs) and the factors associated with surgery, survival, and length of hospitalization in this population. STUDY DESIGN: We analyzed data from infants born preterm (gestational age <37 weeks) enrolled in the multicenter Kids' Inpatient Database of the Healthcare Cost and Utilization Project who were admitted to the hospital within 30 days after birth. Infants with atrial septal defects were excluded. RESULTS: Of 1 429 762 enrolled infants born preterm, 27 434 (2.0%) with CHDs were included. Overall survival to discharge was 90.5%; 74.0% among infants with critical CHDs and 45.7% among infants with hypoplastic left heart syndrome. Cardiac surgeries were performed in 12.2% of all infants born preterm. Rates of surgical intervention for infants with critical CHDs were lower for very low birth weight (≤1.5 kg) vs larger infants >1.5 kg (27% vs 44%), and only 6.3% of infants born with very low birth weight underwent surgeries in Risk-adjustment for Congenital Heart Surgery categories 4 or greater. Greater birth weight, left-sided lesions, care at children's hospitals, and absence of trisomies were associated with a greater likelihood of surgery. Birth weight <2 kg, nonwhite race, trisomy syndromes, prematurity-related morbidities, and Risk-adjustment for Congenital Heart Surgery category 4 or greater were independent predictors of mortality. Birth weight <2 kg, Risk-adjustment for Congenital Heart Surgery category, morbidities, and sidedness of lesion predicted length of stay. CONCLUSIONS: The high survival rates of infants born preterm with CHDs suggests that a cautiously optimistic approach to surgery may be warranted in all but the most immature infants with the greatest-risk conditions.

Hospital-associated venous thromboembolism in children: incidence and clinical characteristics.

OBJECTIVE: To determine incidence and clinical characteristics of hospital-associated venous thromboembolism (VTE) in pediatric patients. STUDY DESIGN: A retrospective analysis of patients with hospital-associated VTE at the Johns Hopkins Hospital from 1994 to 2009 was performed. Clinical characteristics of patients aged 21 years and younger who developed VTE symptoms after 2 days of hospitalization or <90 days after hospital discharge were examined. International Classification of Diseases, Ninth Revision codes were used to categorize patients with complex chronic medical conditions and trauma. RESULTS: There were 270 episodes of hospital-associated VTE in 90,485 admissions (rate 30 per 10,000 admissions). Young adults (18-21 years) and adolescents (14-17 years) had significantly increased rates of VTE compared with children (2-9 years) (incidence rate ratio [IRR] 7.7, 95% CI 5.1-12.0; IRR 4.3, 95% CI 2.7-6.8, respectively). A central venous catheter (CVC) was present in 50% of patients, and a surgical procedure was performed in 45% of patients before VTE diagnosis. For patients without a CVC, trauma was the most common admitting diagnosis. CVC-related VTE was diagnosed most frequently in infants (<1 year old) and in patients with malignancy. Renal and cardiac diseases were associated with the highest rates of VTE (51 and 48 per 10,000, respectively). Rates were significantly higher among those with ≥ 4 medical conditions compared with those with 1 medical condition (IRR 4.0, 95% CI 1.4-8.9). CONCLUSION: Older age and multiple medical conditions were associated with increased rates of hospital-associated VTE. These data can contribute to the design of future clinical trials to prevent hospital-associated VTE in high-risk children.

Variation in feeding practices following the Norwood procedure.

OBJECTIVES: To assess variation in feeding practice at hospital discharge after the Norwood procedure, factors associated with tube feeding, and associations among site, feeding mode, and growth before stage II. STUDY DESIGN: From May 2005 to July 2008, 555 subjects from 15 centers were enrolled in the Pediatric Heart Network Single Ventricle Reconstruction Trial; 432 survivors with feeding data at hospital discharge after the Norwood procedure were analyzed. RESULTS: Demographic and clinical variables were compared among 4 feeding modes: oral only (n = 140), oral/tube (n = 195), nasogastric tube (N-tube) only (n = 40), and gastrostomy tube (G-tube) only (n = 57). There was significant variation in feeding mode among sites (oral only 0%-81% and G-tube only 0%-56%, P < .01). After adjusting for site, multivariable modeling showed G-tube feeding at discharge was associated with longer hospitalization, and N-tube feeding was associated with greater number of discharge medications (R(2) = 0.65, P < .01). After adjusting for site, mean pre-stage II weight-for-age z-score was significantly higher in the oral-only group (-1.4) vs the N-tube-only (-2.2) and G-tube-only (-2.1) groups (P = .04 and .02, respectively). CONCLUSIONS: Feeding mode at hospital discharge after the Norwood procedure varied among sites. Prolonged hospitalization and greater number of medications at the time of discharge were associated with tube feeding. Infants exclusively fed orally had a higher weight-for-age z score pre-stage II than those fed exclusively by tube. Exploring strategies to prevent morbidities and promote oral feeding in this highest risk population is warranted.

Maternal race/ethnicity and survival experience of children with congenital heart disease.

OBJECTIVE: To investigate the existence of racial/ethnic disparity in mortality risk among children with individual congenital heart defects and identify any other risk factors. STUDY DESIGN: The study cohort, comprising children born between 1983 and 2006 with a selected congenital heart defect, was matched to death records to ascertain vital status. The birth and maternal risk factors were obtained from birth certificates. RESULTS: After adjusting for covariates using a multivariate regression model, the risk of mortality was significantly higher in children of non-Hispanic black mothers with transposition of the great arteries (hazard ratio (HR), 1.31; 95% CI, 1.07-1.60), tetralogy of Fallot (HR, 1.34; 95% CI, 1.06-1.69), and coarctation of the aorta (HR, 1.40; 95% CI, 1.10-1.79), compared with children of non-Hispanic white mothers. Time trends analysis examining the mortality risk by survival age and birth period found a significant decrease in 5-year mortality risk from 1983 to 2003 births, with a nearly 50% reduction for hypoplastic left heart syndrome and coarctation of the aorta across 3 maternal racial/ethnic groups examined. CONCLUSION: Our findings may help identify at-risk populations and mortality risk factors and thereby contribute to improved survival and quality of life for these children across the lifespan.