Background Multisystem inflammatory syndrome in children (MIS-C) is a novel condition temporally associated with SARS-CoV2 infection. Cardiovascular involvement is mainly evident as acute myocardial dysfunction in MIS-C. The aim of this study was to describe the cardiac dysfunction in patients with MIS-C, defining the role of severity in the clinical presentations and outcomes in a single cohort of pediatric patients. Methods A single-center retrospective study on patients diagnosed with MIS-C, according to the Center for Disease Control and Prevention (CDC) definition, and referred to Vittore Buzzi Children’s Hospital in Milan from November 2020 to February 2021. Patients were managed according to a local approved protocol. According to the admission cardiac left ventricular ejection fraction (LVEF), the patients were divided into group A (LVEF < 45%) and group B (LVEF ≥45%). Pre-existing, clinical, and laboratory factors were assessed for evaluating outcomes at discharge. Results Thirty-two patients were considered. Cardiac manifestations of MIS-C were reported in 26 patients (81%). Group A included 10 patients (9 M/1F, aged 13 years [IQR 5–15]), and group B included 22 patients (15 M/7 M, aged 9 years [IQR 7–13]). Significant differences were noted among clinical presentations (shock, diarrhea, intensive care unit admission), laboratory markers (leucocytes, neutrophils, and protein C-reactive), and cardiac markers (troponin T and N-terminal pro B-type Natriuretic Peptide) between the groups, with higher compromission in Group A. We found electrocardiogram anomalies in 14 patients (44%) and rhythm alterations in 3 patients (9%), without differences between groups. Mitral regurgitation and coronary involvement were more prevalent in group A. Total length of hospital stay and cardiac recovery time were not statistically different between groups. A recovery of cardiac functioning was reached in all patients. Conclusion Despite significant differences in clinical presentations and need for intensive care, all of the MIS-C patients with significant cardiac involvement in this study completely recovered. This suggests that the heart is an involved organ and did not influence prognosis if properly treated and supported in the acute phase.

Barth syndrome is an X-linked recessive disorder caused by the tafazzin (TAZ) gene mutations and includes dilated cardiomyopathy (DCM) with left ventricular non-compaction, neutropenia, skeletal myopathy, abnormal mitochondria and 3-methylglutaconic aciduria. Dilated cardiomyopathy with left ventricular non-compaction transmitted as an autosomal dominant condition has also been associated with LIM domain-binding 3 (LDB3) gene defects. We describe a family in which the 12-year-old proband had left ventricular non-compaction and DCM. His mother had five miscarriages, two other sons who died in infancy, and a healthy son and daughter. The proband showed left ventricular non-compaction-DCM, skeletal myopathy, recurrent oral aphthous ulcers and cyclic neutropenia. The DCM progressively improved with age; medical therapy was discontinued at 5 years of age. At present, left ventricular function is normal and arrhythmias are absent. Magnetic resonance imaging documented left ventricular non-compaction. However, oral aphthous ulcers and cyclic neutropenia have recurred. In the proband we identified two novel mutations, one of maternal origin in the TAZ gene (p.[Glu202ValfsX15]) and one of paternal origin in the LDB3 gene (p.[Thr350Ile]). The mother, brother and father are healthy; although the latter two show prominent left ventricle trabeculation without dysfunction. Expression studies of TAZ and LDB3 genes were conducted in family members and controls. In the proband, brother and father, LDB3 expression was similar to control cases. TAZ and LDB3 expression progressively declined with age in control both blood and myocardial samples. However, an endomyocardial biopsy performed in the proband at 6 months of age, showed significantly lower TAZ and LDB3 expression than in age-matched myocardial controls. We believe that the clinical, genetic and expression data support the hypothesis that tafazzins are essential during fetal and early post-natal life.

Multisystem inflammatory syndrome in children (MIS-C) is a severe hyperinflammatory disease related to SARS-CoV2 infection, with frequent cardiovascular involvement in the acute setting. The aim of the study was to evaluate the cardiac function at 6 months. Thirty-two patients diagnosed with MIS-C were enrolled and underwent advanced echocardiogram at discharge and at 6 months. According to the left ventricular ejection fraction (LVEF) at admission, the patients were divided into group A (LVEF < 45%) and group B (LVEF ≥ 45%) and the follow-up results were compared. At discharge, all patients had normal LV and RV systolic function (LVEF 61 ± 4.4%, LV global longitudinal strain −22.1%, TAPSE 20.1mm, s’ wave 0.13m/s, RV free wall longitudinal strain −27.8%) with normal LV diastolic function (E/A 1.5, E/e’ 5.7, and left atrial strain 46.5%) and no significant differences at 6 months. Compared to group B, the group A patients showed a reduced, even if normal, LV global longitudinal strain at discharge (−21.1% vs. −22.6%, p 0.02), but the difference was no longer significant at the follow-up. Patients with MIS-C can present with depressed cardiac function, but if treated, the cardiac function recovered without late onset of cardiac disease. This favorable result was independent of the severity of acute LV dysfunction.

Background: Cardiac rhabdomyomas (CRs) are the most common cardiac tumors in newborns. Approximately 80–90% of cases are associated with tuberous sclerosis complex (TSC). In selective cases, Everolimus has resulted in a remarkable tumoral regression effect in children with TS. The optimal dosage for neonates is still unknown. Case presentation: We describe the use of Everolimus in a neonate with multiple biventricular CRs, causing subaortic obstruction, in which a low-dose treatment (0.1 mg/die), in an effort to maintain serum trough levels of 3–7 ng/mL, was successfully used off-label, without adverse effects. Conclusions: We showed that a low-dose Everolimus regimen may be an effective and safe treatment for CR regression in TS neonates, when the minimum therapeutic range was maintained.