Bradycardia associated with Multisystem Inflammatory Syndrome in Children with COVID-19: a case series.

BACKGROUND: Multisystem inflammatory syndrome in children (MIS-C) is a rare life-threatening clinical condition that can develop in patients younger than 21 years of age with a history of infection/exposure to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The cardiovascular system is a main target of the inflammatory process that frequently causes myocardial dysfunction, myopericarditis, coronary artery dilation, hypotension, and shock. Multisystem inflammatory syndrome in children-associated myocarditis is usually characterized by fever, tachycardia, non-specific electrocardiogram abnormalities, and left ventricular dysfunction, but serious tachyarrhythmias may also occur. We report two cases of patients with MIS-C-associated myocarditis who developed severe bradycardia. CASE SUMMARY: Two female adolescents with recent history of coronavirus disease 2019 (COVID-19) were initially hospitalized for long-lasting high-grade fever and severe gastrointestinal symptoms. Both patients were diagnosed with MIS-C-associated myocarditis for elevation of markers of myocardial injury (mean highly-sensitive cardiac troponin 2663 pg/mL, mean N-terminal-pro-brain natriuretic peptide 5097 pg/mL) and left ventricular dysfunction, which was subsequently confirmed by cardiac magnetic resonance. Both patients developed a severe sinus bradycardia (lowest heart rate 36 and 42, respectively), which appeared refractory to the treatment with intravenous Methylprednisolone and Immunoglobulins, despite a clinical and biochemical improvement. The use of Anakinra (a recombinant interleukin-1 receptor antagonist), was associated with a rapid improvement of cardiac rhythm and excellent clinical outcome at 6 months of follow-up. DISCUSSION: In patients with MIS-C-associated myocarditis, a continuous cardiac monitoring is mandatory to promptly identify potential conduction abnormalities. Adolescents may present bradycardia as a rhythm complication. We experienced a rapid recovery after treatment with Anakinra, to be considered as add-on therapy in cases refractory to standard anti-inflammatory treatment.

Left Ventricular Function, Epicardial Adipose Tissue, and Carotid Intima-Media Thickness in Children and Adolescents With Vertical HIV Infection.

BACKGROUND: Life expectancy of HIV patients has increased considerably as a result of antiretroviral therapy (ART), and cardiovascular (CV) disease has emerged as an important late concern. People with HIV infection could have an impaired systolic function; however data on diastolic function and markers of CV risk, such as epicardial adipose tissue (EAT) and intima-media thickness (IMT), are lacking. Aim of this study is to evaluate left ventricular function, EAT, and IMT in children and adolescents with vertically acquired HIV infection. METHODS: We enrolled 29 subjects on ART (13, 45% men; median age of 13.0, and interquartile range 9-18), and 29 age-matched controls. All patients and controls underwent echocardiographic evaluation, with study of the systolic and diastolic function and measurement of the EAT, and a carotid ultrasound study for IMT measurement. RESULTS: Comparing HIV-infected patients to healthy controls, we found a statistically significant increase of EAT and IMT (mean ± SD) (EAT: 3.16 ± 1.05 vs 1.24 ± 0.61 mm; P < 0.0001. IMT: 0.77 ± 0.15 vs 0.51 ± 0.11 mm; P < 0.0001), and a significant reduction of ejection fraction, evaluated with the biplane Simpson method (mean ± SD) (58.5% ± 6.66% vs 66% ± 4.24%; P = 0.029). These results are not related with age, gender, degree of lipodystrophy, dyslipidemia, hyperinsulinism, and ART duration or the use of single antiretroviral classes. CONCLUSIONS: Vertically infected HIV children and adolescents show an increased thickness of EAT and IMT, expression of potentially increased CV risk. They also show an impaired systolic function.

Echocardiographic nomograms for chamber diameters and areas in Caucasian children.

BACKGROUND: Although a quantitative evaluation of cardiac chamber dimensions in pediatric echocardiography is often important, nomograms for these structures are limited. The aim of this study was to establish reliable echocardiographic nomograms of cardiac chamber diameters and areas in a wide population of children. METHODS: A total of 1,091 Caucasian Italian healthy children (age range, 0 days to 17 years; 44.8% female) with body surface areas (BSAs) ranging from 0.12 to 1.8 m(2) were prospectively enrolled. Twenty-two two-dimensional and M-mode measurements of atrial and ventricular chamber diameters and areas were performed. Models using linear, logarithmic, exponential, and square-root relationships were tested. Heteroscedasticity was tested by the White test and the Breusch-Pagan test. Age, weight, height, and BSA, calculated by the Haycock formula, were used as the independent variables in different analyses to predict the mean value of each echocardiographic measurement. The influence of various confounders, including gender, type of delivery, prematurity, and interobserver variability, was also evaluated. Structured Z scores were then computed. RESULTS: The Haycock formula provided the best fit and was used when presenting data as predicted values (mean ± 2 SDs) for a given BSA and within equations relating echocardiographic measurements to BSA. Confounders were not included in the final models, because they did not show significant effects for most of the measurements. CONCLUSIONS: Echocardiographic reference values are presented for chamber area and diameters, derived from a large population of healthy children. These data partly cover a gap in actual pediatric echocardiographic nomograms. Further studies are required to reinforce these data, as well as to evaluate other parameters and ethnicities.

Echocardiographic nomograms for ventricular, valvular and arterial dimensions in caucasian children with a special focus on neonates, infants and toddlers.

BACKGROUND: A quantitative echocardiographic assessment is often essential for the management of congenital heart disease, especially in the first months of life. Despite this, pediatric echocardiographic nomograms are limited and heterogeneous, particularly for neonates and infants. The aim of this study was to establish reliable echocardiographic nomograms in a broad population of healthy Caucasian children. METHODS: Two-dimensional and M-mode measurements of 22 cardiovascular structures were performed. Models using linear, logarithmic, exponential, and square root relationships were tested. Heteroscedasticity was tested using the White and Breusch-Pagan tests. Age, weight, height, and body surface area (BSA; calculated using seven different formulas) were used as the independent variables in different analyses to predict the mean value of each echocardiographic measurement. Structured Z scores were then computed. RESULTS: A total of 445 consecutive Caucasian Italian healthy subjects (age range, 0 days to 36 months; 49% female subjects) with BSAs ranging from 0.12 to 0.67 m(2) were prospectively enrolled. The calculation of BSA using the Haycock formula provided the best results, while other formulas either underestimated (DuBois, Mosteller, Dreyer, and Meban) or overestimated (Boyd and Gehan) BSA. The Haycock formula has been used when presenting data as predicted values (mean ± 2 SDs) for a given BSA and within equations relating echocardiographic measurements to BSA. For all the measurements, there was no significant intraobserver or interobserver variability. CONCLUSIONS: The investigators report new, reliable echocardiographic Z scores derived from a large population of Caucasian neonates, infants, and toddlers calculated using a rigorous statistical design. These nomograms represent a valid diagnostic tool for echocardiographic quantification in this age group.

Diagnostic accuracy and clinical relevance of brain natriuretic peptide assay in pediatric patients with congenital heart diseases.

BACKGROUND: The clinical usefulness of B-type natriuretic peptide (BNP) assay in congenital heart diseases is still controversial. We evaluated the diagnostic accuracy and clinical relevance of this assay in different cardiovascular hemodynamic conditions in pediatric patients with congenital heart diseases. MATERIALS AND METHODS: BNP was measured in 173 healthy individuals and in 382 pediatric patients with congenital heart diseases. We identified five subgroups of hemodynamic conditions: left ventricular volume overload, right ventricular volume overload, left ventricular pressure overload, right ventricular pressure overload, and biventricular volume overload. RESULTS: BNP was higher (P<0.0001) in patients (median 49.0 ng/l, range 0.45-14363 ng/l) than in the reference population (median 6.1 ng/l, range 1.0-29.7 ng/l). BNP assay showed a good diagnostic accuracy in discriminating between healthy individuals and patients (area under the receiver operating characteristic curve 0.95, SE 0.009). Lower BNP values were found in right ventricular pressure overload than in left ventricular pressure overload, left ventricular volume overload, or biventricular volume overload. In the left ventricular volume overload subgroup, BNP significantly correlated with peak systolic gradients (rho=0.622, P<0.001) and left ventricular dilatation (rho=0.35, P=0.03). In the right ventricular volume overload subgroup, BNP correlated with right ventricular pressure (rho=0.622, P<0.001) and right ventricular dilatation (rho=0.377, P=0.0077). Moreover, in cyanotic defects, BNP showed a significant correlation with O2 saturation (rho=0.204 P=0.0128). CONCLUSION: BNP assay showed a good diagnostic accuracy in discriminating between healthy individuals and patients. Congenital heart disease with left ventricular pressure overload and biventricular volume overload has higher BNP values than that with right ventricular pressure overload.

Myocardial infarction and arterial thrombosis in identical newborn twins with homozygosity for the PAI-1 4 G/5 G polymorphism.

Myocardial infarction in the perinatal period, in the absence of congenital heart disease or coronary artery lesions, is rare. The most common etiology described are the thromboembolism and perinatal asphyxia. We report a case of monozygotic twins who developed, after birth, acute vascular events and both had PAI-1 4G/4G homozygosity.

Heat shock protein 70-1 gene expression in pediatric heart surgery using blood cardioplegia.

BACKGROUND: In response to many stress stimuli, cardiomyocytes produce a common set of heat shock proteins (HSP). Up-regulation of HSP70-1 (the inducible isoform) is known to reduce the risk of myocardial cell damage during open-heart surgery and seems to be protective against ischemia. We assessed hsp70-1 gene expression during blood cardioplegic arrest in children undergoing surgical correction of congenital heart defects. METHODS: In tissue samples taken from the right atrium of 59 pediatric patients, we examined hsp70-1 gene expression using a real-time quantitative reverse transcription PCR, with 18S rRNA as internal standard. RESULTS: On average, hsp70-1 gene expression was higher than the baseline level by a factor of 1.44+/- 0.17 (mean+/-SEM). A significant relationship between hsp70-1 mRNA levels and aortic cross-clamp time was observed (R(2)=0.069, p=0.044). Conversely, no significant correlation was observed between hsp70-1 mRNA levels and temperature. CONCLUSIONS: These data suggest that blood cardioplegia can induce an increment in the expression of hsp70-1, confirming its protective role in ischemia/reperfusion injury.