Recurrent Mild Acute Rejections and Donor-specific Antibodies as Risk Factors for Cardiac Allograft Vasculopathy in a National Pediatric Heart Transplant Cohort.

Background: Immune-mediated factors such as acute cellular rejections and donor-specific antibodies (DSAs) are risk factors for cardiac allograft vasculopathy (CAV). We studied a national cohort with a unified setting and thorough protocol endomyocardial biopsy (EMB) data for an association between cellular rejections, especially when mild and recurrent, and DSAs with CAV in pediatric heart transplant (HTx) patients. Methods: This is a retrospective, national cohort study of 94 pediatric HTxs performed between 1991 and 2019 and followed until December 31, 2020. Diagnosis of CAV was based on reevaluation of angiographies. Protocol and indication EMB findings with other patient data were collected from medical records. Associations between nonimmune and immune-mediated factors and CAV were analyzed with univariable and multivariable Cox regression analyses. Results: Angiographies performed on 76 patients revealed CAV in 23 patients (30%). Altogether 1138 EMBs (92% protocol biopsies) were performed on 78 patients (83%). During the first posttransplant year, grade 1 rejection (G1R) appeared in 45 patients (58%), and recurrent (≥2) G1R findings in 14 patients (18%). Pretransplant DSAs occurred in 13 patients (17%) and posttransplant DSAs in 37 patients (39%). In univariable analysis, pretransplant DSAs, appearance and recurrence of G1R findings, and total rejection score during the first posttransplant year, as well as recurrent G1R during follow-up, were all associated with CAV. In multivariable analysis, pretransplant DSAs and recurrent G1R during the first posttransplant year were found to be associated with CAV. Conclusions: Our results indicate that pretransplant DSA and recurrent G1R findings, especially during the first posttransplant year, are associated with CAV after pediatric HTx.

Heart Transplantation for Early-Onset Anthracycline-Induced Cardiomyopathy Within 5 Months of Chemotherapy Completion.

A 9-year-old boy developed progressive anthracycline-induced cardiomyopathy three months after completion of chemotherapy for osteosarcoma. Five months after completion of chemotherapy, at the age of 10 years, heart transplantation was performed. At 29 months since transplantation, the patient remains free of rejection and recurrence of osteosarcoma. (Level of Difficulty: Intermediate.).

Lung Injury After Neonatal Congenital Cardiac Surgery Is Mild and Modifiable by Corticosteroids.

OBJECTIVES: The present study was performed to determine whether lung injury manifests as lung edema in neonates after congenital cardiac surgery and whether a stress-dose corticosteroid (SDC) regimen attenuates postoperative lung injury in neonates after congenital cardiac surgery. DESIGN: A supplementary report of a randomized, double-blinded, placebo-controlled clinical trial. SETTING: A pediatric tertiary university hospital. PARTICIPANTS: Forty neonates (age ≤28 days) undergoing congenital cardiac surgery with cardiopulmonary bypass. INTERVENTIONS: After anesthesia induction, patients were assigned randomly to receive intravenously either 2 mg/kg methylprednisolone or placebo b, which was followed by hydrocortisone or placebo bolus six hours after weaning from CPB for five days as follows: 0.2 mg/kg/h for 48 hours, 0.1 mg/kg/h for the next 48 hours, and 0.05 mg/kg/h for the following 24 hours. MEASUREMENTS AND MAIN RESULTS: The chest radiography lung edema score was lower in the SDC than in the placebo group on the first postoperative day (POD one) (p = 0.03) and on PODs two and three (p = 0.03). Furthermore, a modest increase in the edema score of 0.9 was noted in the placebo group, whereas the edema score remained at the preoperative level in the SDC group. Postoperative dynamic respiratory system compliance was higher in the SDC group until POD three (p < 0.01). However, postoperative oxygenation; length of mechanical ventilation; and tracheal aspirate biomarkers of inflammation and oxidative stress, namely interleukin-6, interleukin-8, resistin, and 8-isoprostane, showed no differences between the groups. CONCLUSIONS: The SDC regimen reduced the development of mild and likely clinically insignificant radiographic lung edema and improved postoperative dynamic respiratory system compliance without adverse events, but it failed to improve postoperative oxygenation and length of mechanical ventilation.

Ventilator-derived dynamic respiratory system compliance: Comparison with static compliance in children.

Measurement of dynamic lung compliance during breathing requires measurement of esophageal pressure, whereas static respiratory system compliance (Crs) method requires several airway occlusions. Despite their precision these compliance methods are cumbersome and not suitable for evaluation of pulmonary system in intensive care. The current ventilators display dynamic Crs, which, however, is seldom utilized in clinical practice. We studied the feasibility of ventilator-derived dynamic Crs measurement in pulmonary evaluation after congenital cardiac surgery in children. In 50 children static Crs was measured by double-occlusion technique, and compared with simultaneous ventilator-derived dynamic Crs values. The early postoperative dynamic and static Crs showed a correlation (r = 0.57, p < 0.0001), but static Crs was 48% higher than dynamic (p < 0.0001). Dynamic Crs measurement showed no correlation with radiographic lung edema findings, whereas the static Crs showed a negative correlation with radiographic lung edema scoring (r = -0.50, p = 0.0002). Thus ventilator-derived dynamic Crs seems less reliable in postoperative pulmonary evaluation than static Crs.

Assessment of extravascular lung water by ultrasound after congenital cardiac surgery.

BACKGROUND: Lung ultrasounds show vertical artifacts known as B-lines in the presence of increased extravascular lung water (EVLW). We aimed to investigate whether lung ultrasound could estimate EVLW after congenital cardiac surgery. METHODS: This prospective observational study comprised 61 children (age range 3 days to 7.4 years) undergoing congenital cardiac surgery. We compared postoperative B-line scores from lung ultrasounds, early postoperative ultrasound as our primary interest, with corresponding postoperative chest radiography (CXR) lung edema scores, with static lung compliance, and with short-term clinical outcome interpreted as time on mechanical ventilation and length of pediatric intensive care unit (PICU) stay. RESULTS: Our findings showed lung ultrasound B-line scores and CXR lung edema scores as correlating 1-6 hr postoperatively (r2 = 0.41, P < 0.0001), on the first postoperative day (r2 = 0.15, P = 0.004) and on the fourth postoperative day (r2 = 0.28, P = 0.008). The B-line score or CXR lung edema score showed no correlation with lung compliance. We found that in multivariable analyses, with length of perfusion and presence of postoperative complications as covariates, both lung ultrasound (P ≤ 0.02) and CXR (P ≤ 0.002) 1-6 hr postoperatively predicted the length of mechanical ventilation and PICU stay. The interobserver variability was less for lung ultrasound B-line score than for CXR lung edema score (P = 0.001). CONCLUSIONS: Our results show that lung ultrasound in assessment of postoperative EVLW predicted length of mechanical ventilation and stay in the PICU, and it had less interobserver variability than CXR. Accordingly, lung ultrasound may complement CXR in assessment of lung edema after surgery for congenital heart defect. Pediatr Pulmonol. 2017;52:345-352. © 2016 Wiley Periodicals, Inc.

Chronic Hypoxemia in Children With Congenital Heart Defect Impairs Airway Epithelial Sodium Transport.

OBJECTIVE: Ambient hypoxia impairs the airway epithelial Na transport, which is crucial in lung edema reabsorption. Whether chronic systemic hypoxemia affects airway Na transport has remained largely unknown. We have therefore investigated whether chronic systemic hypoxemia in children with congenital heart defect affects airway epithelial Na transport, Na transporter-gene expression, and short-term lung edema accumulation. DESIGN: Prospective, observational study. SETTING: Tertiary care medical center responsible for nationwide pediatric cardiac surgery. PATIENTS: Ninety-nine children with congenital heart defect or acquired heart disease (age range, 6 d to 14.8 yr) were divided into three groups based on their level of preoperative systemic hypoxemia: 1) normoxemic patients (SpO2% ≥ 95%; n = 44), 2) patients with cyanotic congenital heart defect and moderate hypoxemia (SpO2 86-94%; n = 16), and 3) patients with cyanotic congenital heart defect and profound systemic hypoxemia (SpO2 ≤ 85%; n = 39). MEASUREMENTS AND MAIN RESULTS: Nasal transepithelial potential difference served as a surrogate measure for epithelial Na transport of the respiratory tract. Profoundly hypoxemic patients had 29% lower basal nasal transepithelial potential difference (p = 0.02) and 55% lower amiloride-sensitive nasal transepithelial potential difference (p = 0.0003) than normoxemic patients. In profoundly hypoxemic patients, nasal epithelial messenger RNA expressions of two airway Na transporters (amiloride-sensitive epithelial Na channel and ß1- Na-K-ATPase) were not attenuated, but instead α1-Na-K-ATPase messenger RNA levels were higher (p = 0.03) than in the normoxemic patients, indicating that posttranscriptional factors may impair airway Na transport. The chest radiograph lung edema score increased after congenital cardiac surgery in profoundly hypoxemic patients (p = 0.0004) but not in patients with normoxemia or moderate hypoxemia. CONCLUSIONS: The impaired airway epithelial amiloride-sensitive Na transport activity in profoundly hypoxemic children with cyanotic congenital heart defect may hinder defense against lung edema after cardiac surgery.

Long-term outcome after treatment of pulmonary atresia with ventricular septal defect: nationwide study of 109 patients born in 1970-2007.

OBJECTIVES: Treatment of pulmonary atresia with ventricular septal defect (PA + VSD) has evolved during recent decades, but it still remains challenging. This study evaluated 41-year experience of outcome, survival and treatment of PA + VSD patients. METHODS: Patient records and angiograms of 109 patients with PA + VSD born in Finland between 1970 and 2007, and treated at the Children's Hospital, Helsinki University Central Hospital, were retrospectively analysed in this nationwide study. RESULTS: Of the 109 patients, 66 (61%) had simple PA + VSD without major aortopulmonary collateral arteries (MAPCAs). Although we observed no difference in overall survival between those with or without MAPCAs, the patients without MAPCAs had better probability to achieve repair (64 vs 28%, P < 0.0003). Only 3 patients were treated by compassionate care. Overall survival was affected by the size of true central pulmonary arteries on the first angiogram (P = 0.001) and whether repair was achieved (P < 0.0001). After successful repair, the survival rate was 93% at 1 year, 91% from the second year, and functional capacity as assessed by New York Heart Association (NYHA) I-II remained in 85% of patients alive at the end of follow-up. Palliated patients at 1, 5, 10 and 20 years of age had Kaplan-Meier estimated survival rates of 55, 42, 34 and 20%, respectively. Patients who underwent repair attempts but were left palliated with right ventricle (RV)-pulmonary artery connection and septal fenestration had better survival than the rest of the palliated patients (P = 0.001). Further, the McGoon index improved after implementation of a systemic-pulmonary artery shunt in the overall PA + VSD population (P < 0.0001). CONCLUSIONS: These findings show that achievement of repair and initial size of true central pulmonary arteries affect survival of patients with PA + VSD. Although the overall survival of patients with MAPCAs showed no difference compared with simple PA + VSD patients, they had a higher risk of remaining palliated. However, palliative surgery may have a role in treatment of PA + VSD because the size of pulmonary arteries increased after placement of systemic-pulmonary artery shunt. In addition, subtotal repair by a RV-pulmonary artery connection and septal fenestration improved survival over extracardiac palliation.