Myocarditis in children after COVID-19 vaccine.

Three healthy adolescents presented with myocarditis confirmed on cardiac magnetic resonance imaging after receiving Pfizer-BioNTech COVID-19 vaccine. All patients were hemodynamically stable and had good short-term outcomes. Long-term outcomes are yet to be determined. Larger studies are needed to determine whether an association between Pfizer-BioNTech COVID-19 vaccine and myocarditis exists.

COVID-19 Vaccination-Associated Myocarditis in Adolescents.

OBJECTIVES: In this study, we aimed to characterize the clinical presentation, short-term prognosis, and myocardial tissue changes as noted on cardiovascular magnetic resonance (CMR) or cardiac MRI in pediatric patients with coronavirus disease 2019 vaccination-associated myocarditis (C-VAM). METHODS: In this retrospective multicenter study across 16 US hospitals, patients <21 years of age with a diagnosis of C-VAM were included and compared with a cohort with multisystem inflammatory syndrome in children. Younger children with C-VAM were compared with older adolescents. RESULTS: Sixty-three patients with a mean age of 15.6 years were included; 92% were male. All had received a messenger RNA vaccine and, except for one, presented after the second dose. Four patients had significant dysrhythmia; 14% had mild left ventricular dysfunction on echocardiography, which resolved on discharge; 88% met the diagnostic CMR Lake Louise criteria for myocarditis. Myocardial injury as evidenced by late gadolinium enhancement on CMR was more prevalent in comparison with multisystem inflammatory syndrome in children. None of the patients required inotropic, mechanical, or circulatory support. There were no deaths. Follow-up data obtained in 86% of patients at a mean of 35 days revealed resolution of symptoms, arrhythmias, and ventricular dysfunction. CONCLUSIONS: Clinical characteristics and early outcomes are similar between the different pediatric age groups in C-VAM. The hospital course is mild, with quick clinical recovery and excellent short-term outcomes. Myocardial injury and edema are noted on CMR. Close follow-up and further studies are needed to understand the long-term implications and mechanism of these myocardial tissue changes.

The Kawasaki Disease Comparative Effectiveness (KIDCARE) trial: A phase III, randomized trial of second intravenous immunoglobulin versus infliximab for resistant Kawasaki disease.

BACKGROUND: Although intravenous immunoglobulin (IVIG) is effective therapy for Kawasaki disease (KD), the most common cause of acquired heart disease in children, 10-20% of patients are IVIG-resistant and require additional therapy. This group has an increased risk of coronary artery aneurysms (CAA) and there has been no adequately powered, randomized clinical trial in a multi-ethnic population to determine the optimal therapy for IVIG-resistant patients. OBJECTIVES: The primary outcome is duration of fever in IVIG-resistant patients randomized to treatment with either infliximab or a second IVIG infusion. Secondary outcomes include comparison of inflammatory markers, duration of hospitalization, and coronary artery outcome. An exploratory aim records parent-reported outcomes including signs, symptoms and treatment experience. METHODS: The KIDCARE trial is a 30-site randomized Phase III comparative effectiveness trial in KD patients with fever ≥36 h after the completion of their first IVIG treatment. Eligible patients will be randomized to receive either a second dose of IVIG (2 g/kg) or infliximab (10 mg/kg). Subjects with persistent or recrudescent fever at 24 h following completion of the first study treatment will cross-over to the other treatment arm. Subjects will exit the study after their first outpatient visit (5-18 days following last study treatment). The parent-reported outcomes, collected daily during hospitalization and at home, will be compared by study arm. CONCLUSION: This trial will contribute to the management of IVIG-resistant patients by establishing the relative efficacy of a second dose of IVIG compared to infliximab and will provide data regarding the patient/parent experience of these treatments.

Cardiac arrest and pulmonary hypertension in scurvy: a case report.

We report a case of a six-year-old boy who presented after a cardiac arrest, likely due to a pulmonary hypertensive crisis in the setting of vitamin C deficiency. After initially presenting with subacute multifocal bone lesions of unknown etiology, he experienced a pulseless electrical activity cardiac arrest while undergoing a diagnostic procedure under sedation. During his post-arrest convalescence, he developed persistent tachycardia and peripheral edema. An echocardiogram revealed findings consistent with significant pulmonary arterial hypertension, which was found to be responsive to inhaled nitric oxide. Laboratory investigation revealed undetectable levels of vitamin C, resulting in disclosure of a history of severe restrictive eating behavior. With ascorbate supplementation, the patient's pulmonary vasodilators were weaned and discontinued. Given his complete recovery, we suspect that the cardiac arrest and pulmonary hypertension were the consequence of a rare, but reversible, complication of scurvy.

A clinical prediction model to estimate the risk for coarctation of the aorta in the presence of a patent ductus arteriosus.

BACKGROUND: Diagnosing coarctation of the aorta (CoA) in the presence of a patent ductus arteriosus (PDA) may require observation until PDA closure. The aim of this study was to create a model incorporating previously published indices to estimate the probability of neonatal CoA in the presence of a PDA. METHODS: A retrospective "investigation" cohort of 80 neonates was divided into two groups: (1) neonates with PDA and suspicion for CoA requiring observation to confirm the presence or absence of CoA and (2) neonates with PDA and confirmed diagnosis of either CoA or unobstructed aortic arch. Multivariate logistic regression was used to create the coarctation probability model (CPM), which was used to calculate a neonate's probability of CoA. The CPM was validated internally using bootstrapping and subsequently validated prospectively using a "validation" cohort of 74 neonates with PDA. RESULTS: The CPM had an area under the receiver operating characteristic curve of 0.96 and demonstrated good clinical significance in the risk stratification of neonates with PDA and CoA. No neonate with a CPM probability of <15% had CoA after PDA closure. Neonates with CPM probability < 15% were classified at low risk, between 15% and 60% at moderate risk, and >60% at high risk for CoA. CONCLUSIONS: On the basis of these results, the authors recommend measurement of the CPM in all neonates with PDA. Those with CPM probability < 15% no longer require observation, which could decrease observation in as many as half of neonates with unobstructed aortic arches; those with CPM probabilities between 15% and 60% require follow-up imaging, while those with CPM probabilities > 60% should be observed as inpatients until PDA closure.

Chronically transfused pediatric sickle cell patients are protected from cardiac iron overload.

Iron overload is a major toxicity of chronic transfusions. Myocardial iron overload is associated with cardiac dysfunction. Cardiac and liver magnetic resonance imaging (MRI) was performed on 14 chronically transfused sickle cell disease (SCD) and non-sickle cell disease (non-SCD) patients seen at Vanderbilt Children's Hospital from 1 January 2000 to 10 March 2010. Retrospective review was conducted to assess cardiac T2*, liver T2*, ventricular dimensions and function, echocardiogram, length of transfusion, hemoglobin, and ferritin measurements. Ten patients had SCD and 4 had non-SCD, including α-thalassemia, ß-thalassemia, and Diamond-Blackfan anemia. Cardiac T2* was normal in all SCD patients (mean 39 ± 12 ms), but abnormal in 3 of 4 non-SCD patients (mean 11.8 ± 2.4 ms). Liver T2* was similar between SCD (mean 6.2 ± 1.6 ms) and non-SCD patients (mean 5.9 ± 1.9 ms), and did not correlate with serum ferritin. Comparing SCD and non-SCD patients with similar transfusion duration, SCD patients had normal cardiac T2* and non-SCD patients had abnormal cardiac T2*. No patients had cardiomyopathy, but ventricular dilatation was common among SCD patients. Chronically transfused pediatric SCD patients are relatively spared of myocardial iron overload, which is unlikely to be due to lower total body iron burden in SCD patients than non-SCD patients.

3-D CT angiographic demonstration of a neonatal ductus arteriosus aneurysm with development of ductal calcification: are the "ductus bump", ductus arteriosus aneurysm, and ductal calcification related?

A "ductus bump" was noted as an incidental finding on a chest radiograph in a newborn infant with congenital cystic adenomatoid malformation. A chest CT performed on the first day of life demonstrated this to be a ductus arteriosus aneurysm (DAA), which subsequently thrombosed. Ductal calcification was noted on follow-up imaging. We propose that the "ductus bump" may actually be a DAA, which resolves presumably by thrombus formation. Ductal calcification may also be related to the regression of the thrombus.