The Diagnostic and Clinical Approach to Pediatric Myocarditis: A Review of the Current Literature

Clinical Effect Analysis of Different Doses of Creatine Phosphate Sodium Combined with Immunoglobulin in the Treatment of Pediatric Viral Myocarditis

The purpose of this paper was to unravel the clinical effect analysis of different doses of creatine phosphate sodium (CPS) combined with immunoglobulin in the treatment of pediatric viral myocarditis (VMC). One hundred and twenty children with VMC were recruited and randomized into three groups (40 patients each). Group I received 1.0 g of CPS dissolved in 100 mL of 5% glucose injection intravenously 1 time/day; group II received 1.25 g of CPS dissolved in 125 mL of 5% glucose injection intravenously 1 time/day; group III received 1.5 g of CPS dissolved in 150 mL of 5% glucose injection intravenously 1 time/day; then all three groups were treated with combined use of immunoglobulin (300-400 mg/day) intravenously once a day; and all three groups were treated for 14 days. The clinical efficacy, cardiac function, serum inflammatory factor levels, immune function, and the occurrence of drug toxicity and adverse effects of the children in the three groups were compared after 14 days of treatment. All three groups achieved better therapeutic effects after treatment, in which the effective rate of the Group II and Group III was notably higher versus the Group I. Lower levels of cTnI, CK-MB, LDH, AST, IL-18, IL-6, IFN-γ, and LVEDD and higher CD3+, CD4+, and CD4+/CD8+, FS, and LVEF values were noted in the Group II and Group III versus the Group I, and the results were more pronounced in the high-dose group. The liver and kidney functions of the children in the three groups before and after treatment did not show any significant changes and the incidence of adverse reactions during the treatment period was low in all three groups. Children with VMC can be treated with high-dose CPS in combination with immunoglobulin, which can improve their cardiac function and immune function and reduce the inflammatory response with good overall therapeutic efficacy and fewer adverse effects.

Pediatric Chest Pain: A Review of Diagnostic Tools in the Pediatric Emergency Department

Pediatric chest pain is a common chief complaint in the emergency department. Not surprisingly, children with chest pain are usually brought to the emergency department by their parents out of fear of heart disease. However, chest pain in the pediatric population is generally a benign disease. In this review, we have identified musculoskeletal pain as the most prevalent etiology of chest pain in the pediatric population, accounting for 38.7-86.3% of cases, followed by pulmonary (1.8-12.8%), gastrointestinal (0.3-9.3%), psychogenic (5.1-83.6%), and cardiac chest pain (0.3-8.0%). Various diagnostic procedures are commonly used in the emergency department for cardiac chest pain, including electrocardiogram (ECG), chest radiography, cardiac troponin examination, and echocardiography. However, these examinations demonstrate limited sensitivity in identifying cardiac etiologies, with sensitivities ranging from 0 to 17.8% for ECG and 11.0 to 17.2% for chest radiography. To avoid the overuse of these diagnostic tools, a well-designed standardized algorithm for pediatric chest pain could decrease unnecessary examination without missing severe diseases.

Diagnostic challenges and forensic implications in a case of infantile fatal myocarditis

We present the case of a 23-month-old child who died less than 24 h after the onset of cardiac symptoms, despite being admitted to the hospital 72 h earlier. Autopsy revealed no significant macroscopic changes, and histologic examination revealed focal lymphocytic myocarditis with myocyte disruption, diffuse alveolar damage in the exudative phase, and generalized lymphocytic immune activation in other organs. Ante-mortem and post-mortem microbiological exams did not clearly prove a causative role of infectious agents. The peculiarity of this case was characterized by the contrast between the severe clinical features and the mild cardiac histological findings. This discrepancy, coupled with the suspicion of a viral causative role based on both ante-mortem and post-mortem microbiological examinations, presented significant challenges in reaching an etiological diagnosis. This case also confirms that the diagnosis of myocarditis in children cannot be made solely on the basis of histological cut-offs or microbiological results. Using abductive reasoning, various diagnostic hypotheses were formulated and evaluated to arrive at the final diagnosis of fatal myocarditis of viral or post-viral origin. Data from post-mortem examination are often the only source of information that is available to the experts, especially in cases of sudden infant death syndrome. In such cases, the forensic pathologists should accurately evaluate findings that may appear to indicate a different etiology, and, in the absence of clinical or radiological data, interpret post-mortem data in a logically correct manner. The autopsy is the first essential step to evaluate the cause of death and must be integrated with the results of ante- and post-mortem diagnostic tests in a holistic approach, which is crucial to allow forensic pathologists to provide an appropriate and relevant opinion.

Adolescent Onset of Acute Heart Failure

Heart failure in adolescents can manifest due to a multitude of causes. Presentation is often quite variable ranging from asymptomatic to decompensated heart failure or sudden cardiac death. Because of the diverse nature of this disease, a thoughtful and extensive evaluation is critical to establishing the diagnosis and treatment plan. Identifying and addressing reversible pathologies often leads to functional cardiac recovery. Some disease states are irreversible and progressive, requiring chronic heart failure management and potentially advanced therapies such as transplantation.

Review of cardiac safety in onasemnogene abeparvovec gene replacement therapy: translation from preclinical to clinical findings

Human gene replacement therapies such as onasemnogene abeparvovec (OA) use recombinant adeno-associated virus (rAAV) vectors to treat monogenic disorders. The heart and liver are known target organs of toxicity in animals; with cardiac and hepatic monitoring recommended in humans after OA dosing. This manuscript provides a comprehensive description of cardiac data from preclinical studies and clinical sources including clinical trials, managed access programs and the post-marketing setting following intravenous OA administration through 23 May 2022. Single dose mouse GLP-Toxicology studies revealed dose-dependent cardiac findings including thrombi, myocardial inflammation and degeneration/regeneration, which were associated with early mortality (4-7 weeks) in the high dose groups. No such findings were documented in non-human primates (NHP) after 6 weeks or 6 months post-dose. No electrocardiogram or echocardiogram abnormalities were noted in NHP or humans. After OA dosing, some patients developed isolated elevations in troponin without associated signs/symptoms; the reported cardiac adverse events in patients were considered of secondary etiology (e.g. respiratory dysfunction or sepsis leading to cardiac events). Clinical data indicate cardiac toxicity observed in mice does not translate to humans. Cardiac abnormalities have been associated with SMA. Healthcare professionals should use medical judgment when evaluating the etiology and assessment of cardiac events post OA dosing so as to consider all possibilities and manage the patient accordingly.

Q wave in paediatric myocarditis: an underinvestigated, readily available prognostic factor

BACKGROUND

Myocarditis is an uncommon disease in children with potentially fatal consequences. An electrocardiogram (ECG) change seen in myocarditis is pathological Q wave. Pathological Q wave is linked to permanent damage and myocardial death in several cardiac diseases. We investigated the significance of pathological Q waves in children with acute myocarditis (AM).

METHODS

This retrospective observational study analysed the data of 59 children with AM admitted to our hospital between January 2016 and July 2021. They were divided into Q wave and non-Q wave myocarditis groups. Patients' laboratory data, echocardiography, treatment and hospital outcome were analysed.

RESULTS

Patients were 64.4% male and had a median age of 6 years and 9 months. Pathological Q waves were found in 52.5% of the patients. Q wave myocarditis group had higher troponin I values (499 vs. 145 ng/L, p = 0.011) and longer hospital stays (13 vs. 9 days, p = 0.020) than the non-Q wave group. They also required higher doses of inotropic or vasoactive drugs. 61.3% of Q wave patients needed mechanical ventilation compared to 35.7% of non-Q wave patients (p = 0.069). All the patients who died or discharged with an LVEF < 30% belonged to the Q wave group.

CONCLUSION

Q wave in AM warrants close monitoring and intensive treatment as it accompanies more severe complications and poorer outcomes. This readily available ECG finding can be a clue to prognoses of AM patients. Further research with larger populations is needed to better understand Q wave prognostic accuracy and its potential role in guiding more expensive treatments.

Viral Heart Disease: Diagnosis, Management, and Mechanisms

"Viral heart disease" is a term encompassing numerous virus-triggered heart conditions, wherein cardiac myocytes are injured, causing contractile dysfunction, cell death, or both. Cardiotropic viruses may also damage interstitial cells and vascular cells. Clinical presentation of the disorder varies widely. In most cases, patients are asymptomatic. Presentation includes-but is not limited to-flu-like symptoms, chest pain, cardiac arrhythmias, heart failure, cardiogenic shock, and sudden cardiac death. Laboratory studies, including blood-based heart injury indicators and cardiac imaging, may be needed. Management of viral heart disease requires a graded approach. Watchful observation at home may be the first step. Closer observation, with additional testing such as echocardiography in the clinic or hospital is less common yet may inform the use of cardiac magnetic resonance imaging. Intensive care may be indicated in severe acute illness. Viral heart disease mechanisms are complex. Initially, damage is predominantly virus mediated, whereas, in the second week, immune responses bring unintended obverse consequences for the myocardium. Innate immunity is largely beneficial in initial attempts to quell viral replication, whereas adaptive immunity brings helpful and antigen-specific mechanisms to fight the pathogen but also introduces the capability of autoimmunity. Each cardiotropic virus family has its own pathogenesis signature, including attack on myocytes, vascular cells, and other constitutive cells of myocardial interstitium. The stage of disease and preponderant viral pathways lend opportunities for potential intervention but also the likelihood of uncertainty about management. Overall, this review provides a novel glimpse into the depth of and need for solutions in viral heart disease.

Eosinophilic Granulomatosis with Polyangiitis in an 8-year-old Girl Manifesting as Hypereosinophilic Syndrome with Myocarditis, Stroke, and Subsequent Orbital Involvement

Hypereosinophilic syndrome (HES) is a heterogeneous group of disorders characterized by peripheral blood eosinophilia of 1.5 × 109/L (1,500/μL) or greater, with evidence of end-organ damage attributable to eosinophilia (e.g., heart, liver or lung) with no other cause for the end-organ damage [1]. Eosinophilic granulomatosis with polyangiitis (EGPA) is a rare disorder that may affect multiple organ systems (lungs, heart, kidneys, or the nervous system). The disorder is characterized by hypereosinophilia in the blood and tissues, inflammation of blood vessels (vasculitis), and the development of inflammatory nodular lesions called granulomatosis [2]. We report a case with a 9-year-old girl presenting with severe hypereosinophilia, ischemic stroke, right-sided hemiparesis and myocarditis treated with methylprednisolone, enoxaparin, rivaroxaban and carvedilol. The patient recovered successfully from myocarditis and stroke but manifested with right-sided orbital involvement as pre- and post-septal orbital cellulitis 10 months later with necrotizing granulomatous perivascular chronic infiltration with eosinophilic infiltration treated with methylprednisolone and subsequent mepolizumab with successful remission of orbital involvement, but severe exogenous Cushing's syndrome and myocardial fibrosis.

Parametric Mapping Cardiac Magnetic Resonance Imaging for the Diagnosis of Myocarditis in Children in the Era of COVID-19 and MIS-C

Myocarditis comprises many clinical presentations ranging from asymptomatic to sudden cardiac death. The history, physical examination, cardiac biomarkers, inflammatory markers, and electrocardiogram are usually helpful in the initial assessment of suspected acute myocarditis. Echocardiography is the primary tool to detect ventricular wall motion abnormalities, pericardial effusion, valvular regurgitation, and impaired function. The advancement of cardiac magnetic resonance (CMR) imaging has been helpful in clinical practice for diagnosing myocarditis. A recent Scientific Statement by the American Heart Association suggested CMR as a confirmatory test to diagnose acute myocarditis in children. However, standard CMR parametric mapping parameters for diagnosing myocarditis are unavailable in pediatric patients for consistency and reliability in the interpretation. The present review highlights the unmet clinical needs for standard CMR parametric criteria for diagnosing acute and chronic myocarditis in children and differentiating dilated chronic myocarditis phenotype from idiopathic dilated cardiomyopathy. Of particular relevance to today’s practice, we also assess the potential and limitations of CMR to diagnose acute myocarditis in children exposed to severe acute respiratory syndrome coronavirus-2 infections. The latter section will discuss the multi-inflammatory syndrome in children (MIS-C) and mRNA coronavirus disease 19 vaccine-associated myocarditis.

Myocarditis in Children: Impact of Early Presentation on Disease Outcomes at a Single Tertiary Center in Saudi Arabia

Purpose

Myocarditis is the inflammation of the heart muscle and can be caused by a variety of infections, incendiary diseases, and pollutants. It is challenging for an emergency pediatrician to have a sufficiently high degree of suspicion for myocarditis to avoid diagnostic delay given the broad overlap of myocarditis symptoms with other disease processes. The study aimed to evaluate the impact of early presentation and diagnosis on the outcomes of acute myocarditis in children.

Patients and Methods

We performed a retrospective analysis of the complete records of 80 pediatric patients diagnosed with acute myocarditis between 2015 and 2019 at a single tertiary center in Saudi Arabia. Patients were two weeks to 14 years of age and were admitted to the pediatric intensive care unit (PICU) for various sequelae of myocarditis. Data from routine clinical and laboratory investigations were collected.

Results

The incidence of delayed presentation at the hospital after the onset of symptoms of myocarditis was 42.5%. A total of 22 (27.5%) patients expired during their hospital stay. There was marginally significant association of earlier presentation with in-hospital survival (80.4% vs 61.8%) and delayed presentation with higher proportion of in-hospital mortality (38.2% vs 19.6%, p=0.064). The rate of mechanical ventilator was also marginally significant in delayed presentation (p=0.068). Shock and multisystem organ failure were the significantly associated manifestations of delayed acute myocarditis presentations. Length of stay in PICU was also significant in delayed presentation group. The impact of presenting symptoms, ECG findings, and use of mechanical ventilator was not significantly associated with delayed presentation.

Conclusion

An earlier presentation may have a substantial impact on overall prognosis and length of PICU stay and may lead to comparatively lesser frequency of mechanical ventilation use.

First Case of Acute Myocarditis Caused by Metapneumovirus in an Immunocompromised 14-year-old Girl

Background

Human metapneumovirus (hMPV) is a paramyxovirus, well known as a causative agent of respiratory tract infections. Non-respiratory manifestations, including cardiac impairments, remain rare. Only two cases of myocarditis caused by hMPV have been described in adults.

Case description

We present the case of a 14-year-old female suffering from Burkitt leukemia and diagnosed with severe myocarditis caused by hMPV, based on results from real-time polymerase chain reaction (RT-PCR) and magnetic resonance imaging (MRI). She was successfully treated by venoarterial extracorporeal membrane oxygenation and intravenous immunoglobulins. She was discharged from pediatric intensive care unit (PICU) 3 weeks later.

Conclusion

This is the first pediatric case of hMPV myocarditis requiring venoarterial extracorporeal membrane oxygenation.

How to cite this article

Makhlouf A, Peipoch L, Duport P, Darrieux E, Reguerre Y, Ramful D, et al. First Case of Acute Myocarditis Caused by Metapneumovirus in an Immunocompromised 14-year-old Girl. Indian J Crit Care Med 2022;26(6):745–747.

Dissecting the cellular landscape and transcriptome network in viral myocarditis by single-cell RNA sequencing

Coxsackievirus B3 (CVB3)-induced myocarditis is commonly employed to study viral pathogenesis in mice. Chronically affected mice may develop dilated cardiomyopathy, which may involve the mediation of immune and nonimmune cells. To dissect this complexity, we performed single-cell RNA sequencing on heart cells from healthy and myocarditic mice, leading us to note significant proportions of myeloid cells, T cells, and fibroblasts. Although the transcriptomes of myeloid cells were mainly of M2 phenotype, the Th17 cells, CTLs, and Treg cells had signatures critical for cytotoxic functions. Fibroblasts were heterogeneous expressing genes important in fibrosis and regulation of inflammation and immune responses. The intercellular communication networks revealed unique interactions and signaling pathways in the cardiac cellulome, whereas myeloid cells and T cells had upregulated unique transcription factors modulating cardiac remodeling functions. Together, our data suggest that M2 cells, T cells, and fibroblasts may cooperatively or independently participate in the pathogenesis of viral myocarditis.

Spectrum of Viral Pathogens Identified in Children with Clinical Myocarditis (Pre-Coronavirus Disease-2019, 2000-2018): Etiologic Agent Versus Innocent Bystander

OBJECTIVE

To identify the etiologies of viral myocarditis in children in the pre-coronavirus disease 2019 era.

STUDY DESIGN

This was a retrospective review of all patients (age <18 years) diagnosed with myocarditis and hospitalized at Rady Children's Hospital San Diego between 2000 and 2018.

RESULTS

Twenty-nine patients met inclusion criteria. Of 28 (97%) patients who underwent testing for viruses, polymerase chain reaction was used in 24 of 28 (86% of cases), and 16 of 24 (67%) detected a virus. Pathogens were rhinovirus (6), influenza A/B (4), respiratory syncytial virus (RSV) (3), coronavirus (3), parvovirus B19 (2), adenovirus (2), and coxsackie B5 virus, enterovirus, and parainfluenza virus type 2 in one case each. Six (21%) patients had no pathogen detected but imaging and other laboratory test results were compatible with myocarditis. Age 0-2 years was associated with RSV, influenza A/B, coronavirus, and enteroviruses (P < .001). Twenty-one patients (72%) experienced full clinical recovery. Three patients (10%) required venoarterial extracorporeal membrane oxygenation (VA-ECMO), and all 3 recovered. Three others (10%) required and underwent successful cardiac transplantation without complications. Two patients (7%) died 9-10 days after hospitalization (1 had RSV and 1 had influenza A/B). Two other patients presented with complete atrioventricular block; 1 case (rhinovirus) resolved spontaneously, and 1 (coronavirus) resolved after support with VA-ECMO. Age <2 years, female sex, lower ejection fraction at admission, and greater initial and peak levels of brain natriuretic peptide were significant predictors of critical outcomes (use of VA-ECMO, listing for cardiac transplantation, and death).

CONCLUSIONS

Viral nucleic acid-based testing revealed a wider spectrum of viruses that could be associated with myocarditis in children than previously reported and traditionally anticipated. A predilection of certain pathogens in the very young patients was observed. Whether the observed range of viral agents reflects an undercurrent of change in viral etiology or viral detection methods is unclear, but the wider spectrum of viral pathogens found underscores the usefulness of polymerase chain reaction testing to explore possible viral etiologies of myocarditis in children.

Arrhythmia spectrum and outcome in children with myocarditis

Introduction

Myocarditis remains an under-diagnosed entity among children. We evaluated the spectrum of electrocardiogram (ECG) changes and arrhythmias in children with myocarditis.

Methods

A single-center prospective observational study was conducted over a period of 18 months at a public university hospital, which included all cases with myocarditis from the ages of 1 month to 12 years. Myocarditis was diagnosed according to standard criteria. Arrhythmias were detected by 12-lead ECG or by multiparameter monitors.

Results

There were 63 children with myocarditis. Sinus tachycardia remained the most important ECG finding (61, 96.8%) followed by ST-T changes (30, 47.6%), low voltage QRS complexes (23, 36.5%), and premature complexes (11, 17.4%). Sustained arrhythmias were seen in 14/63 (22.2%) of the children (Group A), while the remaining 49 patients were designated as Group B. There were 11 (17.5%) cases with sustained tachyarrhythmias, comprising 5 with supraventricular tachycardia, 4 with ventricular tachycardia, and 2 with atrial flutter/fibrillation. Bradyarrhythmias were seen in 3 patients, including 2 children with atrioventricular block and 1 with severe sinus bradycardia. A longer hospital stay of 18.5 (4.75) days vs. 13 (4) days, P = 0.001), and more ST-T changes [12 (85.7%) vs. 18 (36.73%), P = 0.003] were seen in Group A. Multivariate regression analysis found only the presence of ST-T changes as predictors for arrhythmia.

Conclusions

A variety of arrhythmias and other ECG changes were commonly seen in children with myocarditis. Sustained arrhythmias were seen in one-fifth of the patients, being associated with ST-T changes and a longer hospital stay.

Challenges of Diagnosing Viral Myocarditis in Adolescents in the Era of COVID-19 and MIS-C

Myocarditis has a wide array of clinical presentations ranging from asymptomatic to sudden cardiac death. Pediatric myocarditis is a rare disease, with an estimated annual incidence of 1 to 2 per 100,000 children though its true prevalence remains unknown due to its variable and often subclinical presentation. The diagnosis of myocarditis is challenging in the era of COVID-19 and Multisystem Inflammatory Syndrome in Children (MIS-C), which can have overlapping clinical conundrum. Here, we present a case of a 17-year-old male presenting with chest tightness, shortness of breath, and electrocardiogram (EKG) findings concerning for myocardial injury along with elevated inflammatory markers such as D-dimer, ESR (Erythrocyte Sedimentation Rate), and CRP (C-Reactive Protein). We discuss the key elements of our clinical experience with this case and review the literature for pediatric myocarditis, with a focus on differentiating it from MIS-C in the current COVID-19 pandemic era.

Inhibition of calpain reduces cell apoptosis by suppressing mitochondrial fission in acute viral myocarditis

Cardiomyocyte apoptosis is critical for the development of viral myocarditis (VMC), which is one of the leading causes of cardiac sudden death in young adults. Our previous studies have demonstrated that elevated calpain activity is involved in the pathogenesis of VMC. This study aimed to further explore the underlying mechanisms. Neonatal rat cardiomyocytes (NRCMs) and transgenic mice overexpressing calpastatin were infected with coxsackievirus B3 (CVB3) to establish a VMC model. Apoptosis was detected with flow cytometry, TUNEL staining, and western blotting. Cardiac function was measured using echocardiography. Mitochondrial function was measured using ATP assays, JC-1, and MitoSOX. Mitochondrial morphology was observed using MitoTracker staining and transmission electron microscopy. Colocalization of dynamin-related protein 1 (Drp-1) in mitochondria was examined using immunofluorescence. Phosphorylation levels of Drp-1 at Ser637 site were determined using western blotting analysis. We found that CVB3 infection impaired mitochondrial function as evidenced by increased mitochondrial ROS production, decreased ATP production and mitochondrial membrane potential, induced myocardial apoptosis and damage, and decreased myocardial function. These effects of CVB3 infection were attenuated by inhibition of calpain both by PD150606 treatment and calpastatin overexpression. Furthermore, CVB3-induced mitochondrial dysfunction was associated with the accumulation of Drp-1 in the outer membrane of mitochondria and subsequent increase in mitochondrial fission. Mechanistically, calpain cleaved and activated calcineurin A, which dephosphorylated Drp-1 at Ser637 site and promoted its accumulation in the mitochondria, leading to mitochondrial fission and dysfunction. In summary, calpain inhibition attenuated CVB3-induced myocarditis by reducing mitochondrial fission, thereby inhibiting cardiomyocyte apoptosis.

Trends in Acute Myocarditis Related Pediatric Hospitalizations in the United States, 2007-2016

There has been little exploration of acute myocarditis trends in children despite notable advancements in care over the past decade. We explored trends in pediatric hospitalizations for acute myocarditis from 2007 to 2016 in the United States (US). This was a retrospective, serial cross-sectional study of the National Inpatient Sample database from 2007 to 2016, identifying patients ≤18 years hospitalized with acute myocarditis. Patient demographics and incidence trends were examined. Other relevant clinical and resource utilization outcomes were also explored. Out of 60,390,000 weighted pediatric hospitalizations, 6371 were related to myocarditis. The incidence of myocarditis increased from 0.7 to 0.9 per 100,000 children (p <0.0001) over the study period. The mortality decreased from 7.5% to 6.1% (p = 0.02). A significant inflation-adjusted increase by $4,574 in the median hospitalization cost was noted (p = 0.02) while length of stay remained stable (median 6.1 days). Tachyarrhythmias were identified as the most common type of associated arrhythmia. The occurrence of congestive heart failure remained steady at 27%. In conclusion, in-hospital mortality associated with pediatric acute myocarditis has decreased in the United States over years 2007 to 2016 with a concurrent rise in incidence. Despite steady length of stay, hospitalization costs have increased. Future studies investigating long-term outcomes relating to acute myocarditis are warranted.

The use of extracorporeal membrane oxygenation in children with acute fulminant myocarditis

Acute fulminant myocarditis (AFM) occurs as an inflammatory response to an initial myocardial insult. Its rapid and deadly progression calls for prompt diagnosis with aggressive treatment measures. The demonstration of its excellent recovery potential has led to increasing use of mechanical circulatory support, especially extracorporeal membrane oxygenation (ECMO). Arrhythmias, organ failure, elevated cardiac biomarkers, and decreased ventricular function at presentation predict requirement for ECMO. In these patients, ECMO should be considered earlier as the clinical course of AFM can be unpredictable and can lead to rapid haemodynamic collapse. Key uncertainties that clinicians face when managing children with AFM such as timing of initiation of ECMO and left ventricular decompression need further investigation.

Myopericarditis Associated with COVID-19 in a Pediatric Patient with Kidney Failure Receiving Hemodialysis

The outbreak of COVID-19 can be associated with cardiac and pulmonary involvement and is emerging as one of the most significant and life-threatening complications in patients with kidney failure receiving hemodialysis. Here, we report a critically ill case of a 13-year-old female patient with acute pericarditis and bilateral pleurisy, screened positive for SARS-CoV-2 RT-PCR, presented with high fever, frequent dry cough, and dyspnea with tachypnea. COVID-19-induced myopericarditis has been noted to be a complication in patients with concomitant kidney failure with replacement therapy (KFRT). This article brings information in the light of our case experience, suggesting that the direct effect of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection on cardiac tissue was a significant contributor to myopericarditis in our patient. Further studies in this direction are required, as such associations have thus far been reported.

Lupeol alleviates coxsackievirus B3-induced viral myocarditis in mice via downregulating toll-like receptor 4

Objectives

To investigate the effect of lupeol in a mouse model of viral myocarditis induced by coxsackie virus B3 (CVB3).

Methods

Mice were separated into controls (DMEM, n = 20) and CVB3 infected groups (i.e., untreated CVB3 [n = 40]; CVB3 + lupeol 50 mg/kg [n = 40]; CVB3 + lupeol 100 mg/kg [n = 40]; CVB3 + small interfering RNA (siRNA)- toll-like receptor 4 (TLR4) [n = 20]; siRNA + EXP-H mice [n = 20]). Reverse transcription polymerase chain reaction (RT-PCR), western-blot assay, immunohistochemistry, enzyme-linked immunosorbent (ELISA) assay and histopathology were performed to investigate the cardioprotective role of lupeol.

Results

The elevated pro-inflammatory cytokines in CVB3-infected mice (i.e., interleukin-1β [IL-1β]; interleukin-6 [IL-6]; tumour necrosis factor-α [TNF-α]) were significantly reduced by lupeol 50 or 100 mg/kg. Interestingly, the mRNA level and protein level of toll-like receptor 4 (TLR4) were inhibited by lupeol.

Conclusions

Lupeol alleviates CVB3-induced viral myocarditis and myocardial damage in mice. The underlying mechanism may due to downregulation of TLR4.

Role of coxsackie-adenovirus receptor in cardiac development and pathogenesis of congenital heart disease

The coxsackie-adenovirus receptor (CAR) is a cell surface transmembrane protein originally recognized for its role as a binding site for coxsackie- and adeno-viruses. As such, it is believed to play an important role in pathogenesis of myocarditis. Other studies have suggested that CAR also plays an important role in embryonic development, which is not surprising given the strong expression of the receptor in heart, brain, liver, pancreas, kidney, small intestine, and various epithelia during development. A number of studies have looked at downregulation and upregulation of CAR and have confirmed the central role of CAR during critical periods of development. These studies all demonstrated embryonic lethality with variable phenotypes: electrophysiological abnormalities, cardiac structural deformations, and extracardiac abnormalities, such as lymphatic malformations. The purpose of this review is to summarize the existing literature about CAR and formulate some questions for future studies, with an emphasis on the role of CAR during embryonic heart development.

Population Pharmacokinetics of Phosphocreatine and Its Metabolite Creatine in Children With Myocarditis

Objective: This study aimed to develop a parent-metabolite joint population pharmacokinetic model to characterize the pharmacokinetic (PK) profile for phosphocreatine (PCr) and its metabolite creatine (Cr) in children with myocarditis and to use this model to study the PK profile of different dosing schemes. Methods: One hundred pediatric patients with myocarditis were enrolled. Blood samples were collected at baseline and approximately 30, 40 or 50, 75, and 180 min after a single dose of phosphocreatine sodium. Plasma PCr and Cr concentrations were determined using an HPLC-MS/MS method. A nonlinear mixed effect model approach was used to build the population pharmacokinetic model. After validation, the model was used for simulations to evaluate the PK profile of different dosing schemes. Results: A total of 997 plasma concentrations (498 for PCr and 499 for Cr) were included in the analysis. A four-compartment chain model (central and peripheral compartments for both PCr and Cr) with the first-order elimination adequately characterized the in vivo process of PCr and Cr. Allometric scaling based on bodyweight was applied to the PK parameters. The covariate analysis identified that the glomerular filtration rate (GFR) was strongly associated with Cr clearance. Bootstrapping and visual predictive checks suggested that a robust and reliable pharmacokinetic model was developed. The simulation results showed that PCr had no accumulation in vivo. With the infusion of PCr, the concentration of Cr increased rapidly. Conclusion: A joint population pharmacokinetic model for PCr and Cr in pediatric patients with myocarditis was successfully developed for the first time.

Severe cardiac dysfunction in a patient with multisystem inflammatory syndrome in children associated with COVID-19: Retrospective diagnosis of a puzzling presentation. A case report

We report one of the earliest known U.S. cases of multisystem inflammatory syndrome in children associated with COVID-19 (MIS-C). This adolescent male presented prior to any known association between COVID-19 and immune mediated inflammatory syndrome in children. He presented in stable condition and without significant multisystem involvement. During hospitalization, he developed severe left ventricular dysfunction and mixed hypovolemic, distributive and cardiogenic shock. Clinical features overlapped with Kawasaki disease, acute rheumatic fever, and toxic shock syndrome. After centers in Europe began reporting a multisystem inflammatory condition in children with COVID-19, the patient's clinical course and laboratory findings were revisited. He underwent newly available antibody testing and was diagnosed as one of the first known cases of MIS-C in the United States.

Predictors for In-hospital Mortality in Pediatric Patients with Acute Myocarditis – a Retrospective Study

Background: Acute myocarditis, a primary inflammatory cardiac disease commonly caused by viral infection, is an important cause of morbidity and mortality in children. Data obtained from forensic studies found an incidence of 15–33% for acute myocarditis in sudden deaths in the pediatric age group. Currently, there is a lack of data regarding the incidence and factors associated with short-term outcomes in pediatric patients admitted for acute myocarditis.

The aim of the study was to identify predictors for in-hospital mortality in a pediatric population admitted with acute myocarditis.

Material and methods: We conducted a retrospective observational cohort study that included 21 patients admitted for acute myocarditis. Clinical, laboratory, ECG, and imaging data acquired via 2D transthoracic echocardiography and cardiac magnetic resonance imaging were collected from the medical charts of each included patient. The primary end-point of the study was all-cause mortality occurring during hospitalization (period ranging from 10 to 14 days). The study population was divided into 2 groups according to the occurrence of the primary end-point.

Results: The mean age of the study population was 99.62 ± 77.25 months, and 61.90% (n = 13) of the patients were males. The in-hospital mortality rate was 23.9% (n = 5). Patients in the deceased group were significantly younger than the survivors (55.60 ± 56.18 months vs. 113.4 ± 78.50 months, p = 0.039). Patients that had deceased presented a significantly higher level of LDH (365 ± 21.38 U/L vs. 234.4 ± 63.30 U/L, p = 0.0002) and a significantly higher rate of ventricular extrasystolic dysrhythmias (60% vs. 6.25%, p = 0.02, OR: 22.5, 95% CI: 1.5–335) compared to survivors. The 2D echocardiography showed that patients that had deceased presented more frequently an impaired left ventricular ejection fraction (<30%) (p = 0.001) and a significantly higher rate of severe mitral regurgitation (p = 0.001) compared to survivors.

Conclusions: The most powerful predictors for in-hospital mortality in pediatric patients admitted for acute myocarditis were the presence of ventricular extrasystolic dysrhythmias on the 24h Holter ECG monitoring, impaired left ventricular systolic function (LVEF <30%), the presence of severe mitral regurgitation, and confirmed infection with Mycoplasma pneumoniae.

Viral Myocarditis-Incidence, Diagnosis and Management

Viral myocarditis has an incidence rate of 10 to 22 per 100,000 individuals. The presentation pattern of viral myocarditis can range from nonspecific symptoms of fatigue and shortness of breath to more aggressive symptoms that mimic acute coronary syndrome. After the initial acute phase presentation of viral myocarditis, the virus may be cleared, resulting in full clinical recovery; the viral infection may persist; or the viral infection may lead to a persistent autoimmune-mediated inflammatory process with continuing symptoms of heart failure. As a result of these 3 possibilities, the diagnosis, prognosis, and treatment of viral myocarditis can be extremely unpredictable and challenging for the clinician. Herein, the incidence, etiology, definition and classification, clinical manifestation, diagnosis, pathogenesis, prognosis, and treatment of viral myocarditis are reviewed, and how acute clinical care teams might differentiate between viral myocarditis and other acute cardiac conditions is discussed.