Neuroinflammatory Disease following Severe Acute Respiratory Syndrome Coronavirus 2 Infection in Children.

OBJECTIVE: To describe neurologic, radiologic and laboratory features in children with central nervous system (CNS) inflammatory disease complicating severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. STUDY DESIGN: We focused on CNS inflammatory diseases in children referred from 12 hospitals in the Paris area to Necker-Sick Children Reference Centre. RESULTS: We identified 19 children who had a history of SARS-CoV-2 infection and manifest a variety of CNS inflammatory diseases: encephalopathy, cerebellar ataxia, acute disseminated encephalomyelitis, neuromyelitis optica spectrum disorder, or optic neuritis. All patients had a history of SARS-CoV-2 exposure, and all tested positive for circulating antibodies against SARS-CoV-2. At the onset of the neurologic disease, SARS-CoV-2 PCR results (nasopharyngeal swabs) were positive in 8 children. Cerebrospinal fluid was abnormal in 58% (11/19) and magnetic resonance imaging was abnormal in 74% (14/19). We identified an autoantibody co-trigger in 4 children (myelin-oligodendrocyte and aquaporin 4 antibodies), representing 21% of the cases. No autoantibody was found in the 6 children whose CNS inflammation was accompanied by a multisystem inflammatory syndrome in children. Overall, 89% of patients (17/19) received anti-inflammatory treatment, primarily high-pulse methylprednisolone. All patients had a complete long-term recovery and, to date, no patient with autoantibodies presented with a relapse. CONCLUSIONS: SARS2-CoV-2 represents a new trigger of postinfectious CNS inflammatory diseases in children.

Acute Heart Failure in Multisystem Inflammatory Syndrome in Children in the Context of Global SARS-CoV-2 Pandemic.

BACKGROUND: Cardiac injury and myocarditis have been described in adults with coronavirus disease 2019 (COVID-19). Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in children is typically minimally symptomatic. We report a series of febrile pediatric patients with acute heart failure potentially associated with SARS-CoV-2 infection and the multisystem inflammatory syndrome in children as defined by the US Centers for Disease Control and Prevention. METHODS: Over a 2-month period, contemporary with the SARS-CoV-2 pandemic in France and Switzerland, we retrospectively collected clinical, biological, therapeutic, and early outcomes data in children who were admitted to pediatric intensive care units in 14 centers for cardiogenic shock, left ventricular dysfunction, and severe inflammatory state. RESULTS: Thirty-five children were identified and included in the study. Median age at admission was 10 years (range, 2-16 years). Comorbidities were present in 28%, including asthma and overweight. Gastrointestinal symptoms were prominent. Left ventricular ejection fraction was <30% in one-third; 80% required inotropic support with 28% treated with extracorporeal membrane oxygenation. Inflammation markers were suggestive of cytokine storm (interleukin-6 median, 135 pg/mL) and macrophage activation (D-dimer median, 5284 ng/mL). Mean BNP (B-type natriuretic peptide) was elevated (5743 pg/mL). Thirty-one of 35 patients (88%) tested positive for SARS-CoV-2 infection by polymerase chain reaction of nasopharyngeal swab or serology. All patients received intravenous immunoglobulin, with adjunctive steroid therapy used in one-third. Left ventricular function was restored in the 25 of 35 of those discharged from the intensive care unit. No patient died, and all patients treated with extracorporeal membrane oxygenation were successfully weaned. CONCLUSIONS: Children may experience an acute cardiac decompensation caused by severe inflammatory state after SARS-CoV-2 infection (multisystem inflammatory syndrome in children). Treatment with immunoglobulin appears to be associated with recovery of left ventricular systolic function.

Neopulmonary Outflow Tract Obstruction Assessment by 4D Flow MRI in Adults With Transposition of the Great Arteries After Arterial Switch Operation.

BACKGROUND: The main complication in adult patients with transposition of the great arteries (TGA) treated by an arterial switch operation (ASO) is neopulmonary outflow tract stenosis (NPOTS). However, pulmonary flow velocity measurements cannot always be performed with transthoracic echocardiography (TTE) due to complex anatomical features. 4D flow MRI allows detection, quantification, and location of the obstruction site along the NPOTS. PURPOSE AND HYPOTHESIS: To investigate the accuracy of 4D flow for the diagnosis of NPOTS in adults with TGA corrected by ASO. STUDY TYPE: Prospective. POPULATION: Thirty-three adult patients with TGA treated by ASO (19 men, mean age 25.5 years old). FIELD STRENGTH/SEQUENCE: Accelerated 4D flow research sequence at 3T. ASSESSMENT: Maximum NPOTS velocities on TTE and 4D flow MRI done the same day. STATISTICAL TESTS: Pearson correlation coefficient, paired t-test, and Bland-Altman analysis were used to investigate the relationship between TTE and MRI data. RESULTS: In 16 patients (48.5%), evaluation of NPOTS anatomy was not obtained by TTE, while it was always possible by 4D flow. Peak flow velocity (PV) measurements in Doppler and 4D flow were highly correlated (r = 0.78; P < 0.001). PV >350 cm.s-1 was detected in only one patient (3%) by TTE vs. five patients (15%) by 4D flow. Moreover, a high correlation was found between PV and the right ventricle (RV) mass index to body surface area when using 4D flow (r = 0.63; P < 0.001). The location of NPOTS was determined in all patients using 4D flow and concerned the main pulmonary artery in 42%. DATA CONCLUSION: Compared to TTE, 4D flow MRI provides better sensitivity to detect and locate NPOTS in patients with TGA treated by ASO. 4D flow PV measurements in NPOTS were well correlated with TTE PV and RV mass. LEVEL OF EVIDENCE: 1 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2020;51:1699-1705.

Increased aortic pressures and pulsatile afterload components promote concentric left ventricular remodeling in adults with transposition of the great arteries and arterial switch operation.

BACKGROUND: Functional abnormalities of the ascending aorta (AA) have been mainly reported in young patients who underwent arterial switch operation (ASO) for transposition of the great arteries (TGA). OBJECTIVES: To compare systolic, diastolic brachial and central blood pressures (bSBP, bDBP, cSBP, cDBP), aortic biomechanical parameters, and left ventricular (LV) afterload criteria in adult ASO patients with healthy controls and to assess their relationships with LV remodeling and aortic size. MATERIALS AND METHODS: Forty-one prospectively enrolled patients (16.8 to 35.8 years) and 41 age- and sex-matched healthy volunteers underwent cardiac MRI to assess LV remodeling with simultaneous brachial BP estimation. After MRI, carotid-femoral tonometry was performed to measure pulse wave velocity (cfPWV), cSBP and cDBP for further calculation of pulse pressure (cPP), AA distensibility (AAD), and AA and LV elastance (AAE, LVE). RESULTS: bSBP, bDBP, cSBP,cDBP and cPP were all significantly higher in ASO group than in controls: cSBP (116.5 ± 13.8 vs 106.1 ± 12.0, p < 0.001), cDBP (72.5 ± 6.9 vs 67.1 ± 9.4, p = 0.002), cPP (44.0 ± 12.1 vs 39.1 ± 8.9, p = 0.003) and not related to aortic size. AAD were decreased in ASO patients vs controls (4.70 ± 2.72 vs 6.69 ± 2.16, p < 0.001). LV mass was correlated with bSBP, cSBP, cPP (ρ = 0.48; p < 0.001), while concentric LV remodeling was correlated with AAE (ρ = 0.60, p < 0.001) and LVE (ρ = 0.32, p = 0.04), but not with distensibility. CONCLUSION: Even without reaching arterial hypertension, aortic sBP and PP are increased in the adult TGA population after ASO, altering the pulsatile components of afterload and contributing to LV concentric remodeling.

Outcomes after aortic coarctation repair in neonates weighing less than 2000 g.

BACKGROUND: Preterm birth is common in children with congenital heart disease. However, data on how to manage low-birth-weight infants with aortic coarctation are scarce and outcomes are poorly reported. Surgery is often delayed in these infants because gaining weight is supposed to improve mortality and to reduce the risk for recoarctation. METHODS: All infants weighing less than 2000 g who underwent repair for aortic coarctation at our institution between January 2017 and December 2020 were included in a retrospective study. Baseline characteristics, medical and surgical management, and outcomes, including recoarctation, death, and complications of preterm birth, were analyzed. RESULTS: A total of 15 patients had coarctation repair at a median age of 15 days and at a median weight of 1585 g. Infants with a birth weight <1200 g were operated on later and did not have higher recoarctation rates compared to those with a birth weight >1200 g. The recoarctation rate was 26.6% and one infant died of an extracardiac cause. Concerning prematurity-related complications, we observed 40% of bronchopulmonary dysplasia, 40% of intraventricular hemorrhage, and 27% of retinopathy of prematurity. These complications were more prevalent in children with a birth weight of <1200 g. CONCLUSION: Delaying surgery beyond 15 days to gain weight does not appear to decrease the risk of recoarctation and may be deleterious in low-birth-weight infants who are exposed for a longer period to risk factors of prematurity-related complications.

Severe Bacterial Infection Initially Misdiagnosed as MIS-C: Caution Needed.

Working in the era of the novel coronavirus disease 2019 can predispose to cognitive bias. We present a case of life-threatening bacterial infection misdiagnosed as multisystem inflammatory syndrome in children. While multisystem inflammatory syndrome in children-related myocardial dysfunction is now a well-recognized complication of coronavirus disease 2019, a rigorous differential diagnosis approach, notably for infectious etiologies, is paramount.

Multisystem inflammatory syndrome in children: Inputs of BNP, NT-proBNP and Galectin-3.

BACKGROUND: Since the COVID-19 pandemic began, a cohort of Multisystem inflammatory syndrome in children (MIS-C) patients has been described. Cardiac involvement is found in 80-85% patients, typically with cardiac dysfunction with or without cardiogenic shock. Here, three cardiac biomarkers, BNP, NT-proBNP and Galectin-3 were compared for the first time in MIS-C in a unique cohort of hospitalized French children. METHODS: Fourteen children with MIS-C hospitalized at Necker-Enfants Malades for cardiac management during the first three COVID-19 waves (March 2020-March 2021) were included. All had positive SARS-CoV-2 serology and proven cardiac involvement assessed by transthoracic echocardiography. NT-proBNP, BNP and Galectin-3 were measured at admission, discharge and first follow-up clinic. RESULTS: All admission Galectin-3 measurements were comprised within the reference interval, both in patients with and without cardiogenic shock, and did not vary between admission, discharge and first follow-up clinic. Both median admission BNP and NT-proBNP were higher in children with cardiogenic shock than without. Median admission NT-proBNP was higher than its predictive positive value in heart failure in both groups of children, while median BNP was below its negative predictive value in children without cardiogenic shock but with cardiac dysfunction. CONCLUSIONS: Galectin-3 does not seem affected by MIS-C. NT-proBNP seems to increase more precociously than BNP possibly making it a more sensitive marker for screening of heart failure in MIS-C.

Exercise electrocardiogram for risk-based screening of severe residual coronary lesion in children after coronary surgery.

BACKGROUND: Residual severe coronary artery (CA) lesion (SCL) in children after cardiac surgery involving the CA is a major concern. AIM: To evaluate the value of exercise electrocardiogram (eECG) for risk-based screening of SCL. METHODS: We analysed 135 maximal eECG from 115 children (mean age 13.6±3.7 years) who underwent concomitant CA imaging. SCL was defined as a stenosis exceeding 50%. RESULTS: Underlying congenital heart diseases were transposition of the great arteries (TGA) (n = 116), CA pathway anomaly (n = 13) and left CA from the pulmonary artery (n = 6). Eleven SCLs were identified in 10 patients, of which 3 had a known untreated non-severe lesion and 4 had no lesions on previous imaging. In multivariable analysis, risks markers for SCL were effort chest pain (OR: 4.72, 95% CI: 1.23-18.17; P=0.024), intramural pathway (OR: 4.37, 95% CI: 1.14-16.81; P=0.032). Yacoubs C-type CA was added as a risk marker for patients with TGA (P=0.0009). All patients with SCL had a positive eECG (sensitivity: 100%, 95% CI: 72-100). Specificity was 81% (95% CI: 73-87). In the low-risk group (0 risk markers), 3/95 patients had SCL (3%), and the post-test probability of SCL with positive eECG (PPr+) was 15% (95% CI: 8-21). In the high-risk group (≥1 risk marker) comprising 8/40 SCLs (20%), PPr+ was 53% (95% CI: 35-67). CONCLUSIONS: Most SCL tended to develop gradually, years after surgery. Provided it is near maximal, a negative eECG appears sufficient to exclude SCL. In the high-risk group, PPr+ exceeded 50%.

Outcomes after common arterial trunk repair: Impact of the surgical technique.

OBJECTIVES: We compared the risk of mortality and reintervention after common arterial trunk (CAT) repair for different surgical techniques, in particular the reconstruction of the right ventricle outflow tract with left atrial appendage (LAA) without a monocusp. METHODS: The study population comprised 125 patients with repaired CAT who were followed-up at our institution between 2000 and 2018. Statistical analysis included Cox proportional hazard models. RESULTS: Median follow-up was 10.6 years. The 10-year survival rate was 88.2% (95% confidence interval [CI], 80.6-92.4) with the poorest outcome for CAT type IV (64.3%; 95% CI, 36.8-82.3; P < .01). In multivariable analysis, coronary anomalies (hazard ratio [HR], 11.63 [3.84-35.29], P < .001) and CAT with interrupted aortic arch (HR, 6.50 [2.10-20.16], P = .001) were substantial and independent risk factors for mortality. Initial repair with LAA was not associated with an increased risk of mortality (HR, 0.37 [0.11-1.24], P = .11). The median age at reintervention was 3.6 years [7.3 days-13.1 years]. At 10 years, freedom from reintervention was greater in the group with LAA repair compared with the valved conduit group, 73.3% (95% CI, 41.3-89.4) versus 17.2% (95% CI, 9.2-27.4) (P < .001), respectively. Using a valved conduit for repair (HR, 4.79 [2.45-9.39], P < .001), truncal valve insufficiency (HR, 2.92 [1.62-5.26], P < .001) and DiGeorge syndrome (HR, 2.01 [1.15-3.51], P = .01) were independent and clinically important risk factors for reintervention. CONCLUSIONS: For the repair of CAT, the LAA technique for right ventricle outflow tract reconstruction was associated with comparable survival and greater freedom from reintervention than the use of a valved conduit.

A monocyte/dendritic cell molecular signature of SARS-CoV-2-related multisystem inflammatory syndrome in children with severe myocarditis.

BACKGROUND: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in children is generally milder than in adults, but a proportion of cases result in hyperinflammatory conditions often including myocarditis. METHODS: To better understand these cases, we applied a multiparametric approach to the study of blood cells of 56 children hospitalized with suspicion of SARS-CoV-2 infection. Plasma cytokine and chemokine levels and blood cellular composition were measured, alongside gene expression at the bulk and single-cell levels. FINDINGS: The most severe forms of multisystem inflammatory syndrome in children (MIS-C) related to SARS-CoV-2 that resulted in myocarditis were characterized by elevated levels of pro-angiogenesis cytokines and several chemokines. Single-cell transcriptomics analyses identified a unique monocyte/dendritic cell gene signature that correlated with the occurrence of severe myocarditis characterized by sustained nuclear factor κB (NF-κB) activity and tumor necrosis factor alpha (TNF-α) signaling and associated with decreased gene expression of NF-κB inhibitors. We also found a weak response to type I and type II interferons, hyperinflammation, and response to oxidative stress related to increased HIF-1α and Vascular endothelial growth factor (VEGF) signaling. CONCLUSIONS: These results provide potential for a better understanding of disease pathophysiology. FUNDING: Agence National de la Recherche (Institut Hospitalo-Universitaire Imagine, grant ANR-10-IAHU-01; Recherche Hospitalo-Universitaire, grant ANR-18-RHUS-0010; Laboratoire d'Excellence ''Milieu Intérieur," grant ANR-10-LABX-69-01; ANR-flash Covid19 "AIROCovid" and "CoVarImm"), Institut National de la Santé et de la Recherche Médicale (INSERM), and the "URGENCE COVID-19" fundraising campaign of Institut Pasteur.