Diagnosis and Management of Myocarditis in Children: A Scientific Statement From the American Heart Association

Radiologic evaluation of a giant aneurysmal left circumflex coronary artery presenting with palpitation: A Cas of successful diagnosis

Coronary artery aneurysms (CAAs) are rare cardiovascular abnormalities often associated with conditions like atherosclerosis, connective tissue disorders, or vasculitis. We report a case of a 39-year-old woman presenting with palpitations and dysphagia, ultimately diagnosed with a giant aneurysmal left circumflex coronary artery using a multimodal imaging approach. Initial echocardiography identified a cystic lesion within the left atrium, prompting further evaluation with cardiac magnetic resonance (CMR), computed tomography (CT), and coronary catheterization. These modalities confirmed a large LCX aneurysm measuring 6.3 × 7.9 cm with left main coronary artery dilation. While surgical intervention was recommended, the patient opted for medical management. This case underscores the critical role of advanced imaging in diagnosing and managing complex cardiac conditions.

A Prediction Rule to Identify Children and Young Adults at Low Risk for Myocarditis

OBJECTIVE

(1) To derive a prediction rule for pediatric myocarditis that distinguishes low-risk patients for whom additional work-up, including venipuncture or cardiac imaging, may be avoided, (2) to assess the test characteristics of troponin in our study population.

METHODS

This retrospective case-control study included all patients who presented to a pediatric emergency department between 2010 and 2021 and underwent troponin testing for suspected myocarditis. Myocarditis cases (identified using American Heart Association criteria) and controls were to approximate a 1:2 ratio. Logistic regression with forward selection was used to derive a prediction rule for myocarditis. As the goal was to derive a rule for low-risk children, in whom venipuncture would be unnecessary, laboratory results were analyzed separately.

RESULTS

We identified 93 case patients and 202 control patients. The final prediction rule included chest pain [adjusted odds ratio (aOR): 3.5, 95% CI: 1.8 to 7.0], reported or measured fever (aOR: 1.7, 95% CI: 1.0 to 3.1,) and atrioventricular conduction delays or ST segment changes (aOR: 2.6, 95% CI: 1.4 to 4.7). Sensitivity, calculated as the proportion of cases with at least one of the 3 predictors was 99% (95% CI: 0.94 to 0.99), and specificity was 14% (95% CI: 0.09 to 0.20). With at least 2 predictors, sensitivity was 60% (95% CI: 0.50 to 0.71) and specificity was 72% (95% CI: 0.65 to 0.78).

CONCLUSION

The prediction rule developed can help identify children at low risk for myocarditis and, therefore, avoid troponin testing and/or further evaluation including cardiology consult or cardiac imaging. Specificity was insufficient to rule in myocarditis without additional investigation.

Infarct-like myocarditis in adolescents: Exploring genetic insights from diagnosis through follow-up

BACKGROUND

Myocarditis has traditionally been considered an acquired condition, but recent evidence suggests a genetic contribution, primarily in complicated cases. Data on pediatric uncomplicated or infarct-like myocarditis remain scarce. This study aimed to assess the prevalence of pathogenic or likely pathogenic (P/LP) variants in adolescents with infarct-like myocarditis and their association with clinical and imaging findings.

METHODS

This prospective, multicenter study included 30 adolescents diagnosed with infarct-like myocarditis across five hospitals in Catalunya, Spain (2016-2024). Diagnosis was confirmed using the 2018 Lake Louise Criteria on cardiac magnetic resonance imaging (CMR). Follow-up CMR was performed at 12 months, and genetic testing was conducted using a next-generation sequencing panel targeting 174 genes associated with inherited cardiac diseases.

RESULTS

P/LP variants in cardiomyopathy-associated genes were identified in 22.2 % of patients. Baseline CMR showed no significant differences in ventricular function or LGE extent, but a ring-like LGE pattern was significantly associated with genetic findings (p = 0.025), while septal involvement showed a p-value of 0.056. Over a median follow-up of 3 years (IQR 2-7), 9 patients (30 %) experienced recurrent myocarditis, more frequently in genetic-positive patients (66.7 % vs. 23.8 %). At 12 months, genetic-positive patients exhibited a greater LGE burden (p = 0.047) and persistent myocardial edema on T2-STIR (p = 0.009), suggesting ongoing myocardial remodeling.

CONCLUSIONS

The high prevalence of P/LP variants in infarct-like myocarditis highlights the need for genetic testing, particularly in patients with a ring-like LGE pattern or septal involvement. Persistent CMR abnormalities and symptomatic recurrences in genetic-positive cases support long-term monitoring, even in seemingly uncomplicated presentations.

Comprehensive analysis of glycometabolism-related genes reveals PLOD2 as a prognostic biomarker and therapeutic target in gastric cancer

BACKGROUND

Gastric cancer (GC) is one of the leading causes of cancer-related mortality worldwide, with limited therapeutic options and a poor prognosis, particularly in advanced stages. Glycometabolism, a hallmark of cancer, plays a critical role in tumor progression, immune evasion, and response to therapy. However, the specific roles of glycometabolism-related genes and their prognostic and therapeutic implications in GC remain inadequately understood.

METHODS

Transcriptomic and clinical data from GC patients were retrieved from TCGA and GEO databases. Glycometabolism-related genes were identified and analyzed using machine learning algorithms to construct a prognostic model. Functional assays, immune profiling, and pathway enrichment analyses were performed to explore the roles of these genes in tumor progression, immune-modulatory effects, and drug resistance. PLOD2, the gene with the highest prognostic significance, was further investigated to uncover its underlying regulatory mechanisms, roles in immune modulation, and contribution to therapeutic resistance.

RESULTS

A glycometabolism-related prognostic model consisting of four genes (PLOD2, CHSY3, SLC2A3 and SLC5A1) was developed and validated, effectively stratifying GC patients into high- and low-risk subgroups with distinct survival outcomes. Among these, PLOD2 emerged as the most significant gene, exhibiting strong associations with tumor progression and poor survival. Functional analyses revealed that PLOD2 promotes glycolysis and tumor progression through activation of the PI3K/AKT/mTOR pathway. Immune profiling revealed that PLOD2 overexpression is associated with an immunosuppressive tumor microenvironment, characterized by increased M2 macrophage infiltration and reduced immune activity. Moreover, treatment with rapamycin, an mTOR inhibitor, significantly suppressed PLOD2-mediated proliferation and anchorage-independent growth in GC cells, highlighting the central role of the PI3K/AKT/mTOR pathway in PLOD2-driven oncogenic behaviors.

CONCLUSIONS

This study identifies PLOD2 as a key prognostic biomarker and therapeutic target in gastric cancer. As a central component in a glycometabolism-related model, PLOD2 promotes glycolysis, tumor progression, and immune evasion via the PI3K/AKT/mTOR pathway. The model effectively stratifies patient risk, offering both prognostic utility and therapeutic insight. Targeting PLOD2-mediated pathways may represent a promising strategy for precision therapy and improved clinical outcomes in gastric cancer.

Hydroxychloroquine cures autoimmune myocarditis by inhibiting the innate immune system via the C-X-C motif chemokine ligand 16 and C-X-C motif receptor 6 axis between macrophages and T cells

BACKGROUND AND PURPOSE

Myocarditis is a life-threatening inflammatory disease, but lacks effective treatment options. Hydroxychloroquine (HCQ), an established antimalarial agent, is used widely to manage rheumatic disorders. This research aimed to evaluate the efficacy of HCQ in treating myocarditis.

EXPERIMENTAL APPROACH

A mouse model of experimental autoimmune myocarditis (EAM) was used to evaluate the therapeutic effects of HCQ on cardiac function, inflammation and fibrosis. Echocardiography, histology and cytokine assays were performed to assess cardiac function and inflammatory responses. Single-cell RNA sequencing was employed to analyse immune cell populations and chemotactic activity. C-X-C motif chemokine ligand 16 (CXCL16) levels were measured in cardiac tissue and serum, while YY1 expression was measured by western blotting in macrophages and cardiac tissue. Flow cytometry was used to evaluate immune cell infiltration and migration.

KEY RESULTS

HCQ improved cardiac function in acute and chronic myocarditis. HCQ treatment reduced inflammation, fibrosis and immune cell infiltration in myocarditis models. Single-cell RNA sequencing revealed that HCQ lowered inflammatory cell proportions and suppressed macrophage chemotaxis. HCQ reduced YY1 levels, leading to the down-regulation of CXCL16 expression in macrophages and inhibition of CXCL16-mediated chemotaxis to Th17 and natural killer T (NKT) cells. CXCL16 neutralizing antibodies improved cardiac function and reduced inflammation in myocarditis.

CONCLUSION AND IMPLICATIONS

HCQ improves cardiac function and reduces inflammation in myocarditis by inhibiting CXCL16 expression in macrophages, by suppressing its transcription factor YY1, which in turn reduced the chemotaxis of Th17 and NKT cells. HCQ is a promising therapeutic agent for myocarditis.

CMR Findings in the Long-Term Outcomes After Multisystem Inflammatory Syndrome in Children (MUSIC) Study

BACKGROUND

Multisystem Inflammatory Syndrome in Children is characterized by high rates of acute cardiovascular involvement with rapid recovery of organ dysfunction. However, information regarding long-term sequelae is lacking. We sought to characterize the systolic function and myocardial tissue properties using cardiac magnetic resonance (CMR) imaging in a multicenter observational cohort of Multisystem Inflammatory Syndrome in Children patients.

METHODS

In this observational cohort study, comprising 32 centers in North America, CMR studies were analyzed by a core laboratory to assess ventricular volumetric data, tissue characterization, and coronary involvement.

RESULTS

A total of 263 CMRs from 255 Multisystem Inflammatory Syndrome in Children patients were analyzed. The mean patient age was 11.4±4.4 years. Most studies were performed at 3 months (33%) or 6 months (45%) after hospitalization. Left ventricular dysfunction was present in 17 (6.7%) of the first CMRs and was never worse than mild. Dysfunction was observed in 4/7 (57%) patients at admission, 5/87 (6.9%) patients at 3 months, and 6/129 (4.6%) patients imaged either at 6 months or 1 year post-hospitalization. Late gadolinium enhancement was present in 2 (0.8%) patients, 1 at 3 months and another at 6 months following hospitalization. Coronary artery dilation was present in 13 of the 174 (7.5%) patients. Nine patients met the Lake Louise criteria for myocarditis (3.5%) at the time of CMR.

CONCLUSIONS

In this largest published multiinstitutional longitudinal CMR evaluation of confirmed Multisystem Inflammatory Syndrome in Children patients, the prevalence of ventricular dysfunction and myocardial tissue characterization abnormalities on medium-term follow-up was low. However, a small number of patients had mild residual abnormalities at 6 months and 1 year following hospitalization.

REGISTRATION

URL: https://www.clinicaltrials.gov; Unique identifier: NCT05287412.

Holodiastolic Flow Reversal in the Descending Aorta: A Marker of Concomitant Acute Myocarditis and Aortitis in Children-A Case Series

This case series describes five pediatric patients with acute myocarditis presenting holodiastolic flow reversal in the descending aorta despite the absence of aortic run-off lesions. This Doppler finding highlights the role of aortitis or Concomitant Acute Myocarditis and Aortitis (CAMA). Cardiac magnetic resonance imaging (MRI) with late gadolinium enhancement (LGE) confirmed myocarditis in three cases. Key findings included poor response to exogenous catecholamines, elevated troponin I, hyponatremia, low vitamin D, and frequent biventricular involvement. Outcomes included one successful cardiac transplantation, one requiring levosimendan, and three fatalities. Low diastolic blood pressure and flow reversal in the descending aorta are critical clues for diagnosing CAMA. Clinical implications, pathophysiology, and management are discussed.

Missed or Delayed Diagnosis of Heart Disease by the General Pediatrician

Missed or delayed heart disease diagnoses pose a major challenge in pediatric primary care. Many cardiac conditions present with subtle or nonspecific symptoms that resemble benign childhood illnesses, making their prompt recognition difficult. This review describes congenital and acquired heart diseases prone to diagnostic delays, including critical congenital heart disease, coarctation of the aorta, atrial and ventricular septal defects, myocarditis, Kawasaki disease, heart failure, and pulmonary arterial hypertension. The atypical presentations of these disorders and the associated diagnostic pitfalls are emphasized. Furthermore, the importance of alarming symptoms and signs, such as chest pain, palpitations, syncope, and abnormal heart murmurs, is underscored. A structured approach to these red flags is presented to assist primary care pediatricians in identifying children at risk, initiating appropriate management, and referring them for specialized evaluation. The importance of preparticipation screening for athletes is also discussed, highlighting how it can be applied to all children during routine health visits to identify those with heart disease. Appropriate training is essential to increase pediatricians' ability to recognize and manage cardiac patients.

Macrophage-derived SPP1 exacerbate myocardial injury by interacting with fibroblasts in viral myocarditis

BACKGROUND

Viral myocarditis (VMC) is an inflammatory myocardial condition triggered by viral infections which involves pathogenic-related damage and immune-mediated damage. However, the precise immunopathogenic mechanisms underlying VMC remain elusive.

METHODS

We performed single-cell RNA sequencing on mouse hearts during the acute phase of CVB3-induced VMC. After manually annotating cell types, functional analyses of macrophage were performed by cell ratio changes, customized gene set module scoring and CellPhoneDB. Utilizing indirect co-culture experiments in vitro, the effects of macrophage-derived SPP1 on cardiac fibroblasts were investigated. Depletion of macrophages and inhibition of SPP1 expression in mice were carried out to study the effects of macrophage-derived SPP1 on cardiac function, inflammation levels, and myocardial injury in mice with VMC.

RESULTS

Our data revealed that macrophages are the major immune cells which infiltrate the heart during the acute phase of VMC, particularly a macrophage subpopulation which highly expresses Spp1 (Spp1+ macrophages) and exhibited characteristics of peripheral blood monocytes. Spp1+ macrophages communicate extensively with fibroblasts during VMC, and that SPP1 promotes fibroblast conversion to an inflammatory phenotype with high Ccl2/Ccl7 expression. This in turn increases monocyte chemotaxis to the heart. Besides, a partial depletion of macrophages in the early stages of VMC attenuated myocardial inflammation and myocardial injury in mice. Inhibition of SPP1 reduced cardiac macrophage infiltration, attenuated myocardial inflammation, and improved cardiac function in VMC mice.

CONCLUSION

Our findings suggested that Spp1+ macrophages could self-recruit, and macrophage-derived SPP1 exacerbated myocardial immune injury by promoting high Ccl2/Ccl7 expression in fibroblasts. Our study advances understandings of VMC pathogenesis, and provides novel insight into potential immunotherapies for VMC.

Diagnostic efficacy of soluble ST2 in pediatric fulminant myocarditis

Background and aims

Early identification of fulminant myocarditis (FM) is the key to reducing mortality, but there is still a lack of effective biomarkers for diagnosis. The aim of this study was to investigate the value of soluble ST2 (sST2) in identifying FM in children.

Methods

This was a single-center clinical observational study. We consecutively enrolled 144 children younger than 14 years of age diagnosed with viral myocarditis between January 2018 and November 2023, of whom 63 were diagnosed with FM.

Results

The sST2 level in the FM group was significantly higher than that in the non-FM group [104.40 (68.80, 150.10) vs. 38.30 (19.85, 55.05), p < 0.001]. ROC curves showed that the optimal cut-off values of sST2, TNI, NT-proBNP and CRP for FM were 63.8 ng/ml, 13.3 ng/ml, 3182 pg/ml and 26.5 mg/L, respectively. The sensitivity and specificity of sST2 were 84.13% and 88.9%, indicating the highest early diagnosis efficiency. Multifactorial correction showed that sST2 ≥ 63.8 ng/ml and NT-proBNP ≥ 3182 pg/ml were independent diagnostic predictors of FM (OR = 22.374, 95% CI: 8.140 ∼ 61.499, P < 0.001), and (OR = 3.208, 95% CI: 1.163 ∼ 8.846, P = 0.024).

Conclusions

With high sensitivity and specificity, sST2 may serve as a strong predictor of pediatric FM.

Design and rationale of the COVID vaccine-associated myocarditis/pericarditis (CAMP) study

BACKGROUND

Minimal data are available on mid- and long-term outcomes following COVID-19 vaccine-associated myocarditis/pericarditis. The COVID Vaccine-Associated Myocarditis/Pericarditis (CAMP) study aims to characterize the mid- and long-term sequelae of myocarditis/pericarditis following administration of any Pfizer-BioNTech COVID-19 vaccine (herein referred to as COMIRNATY®). Herein we describe the rationale and design of CAMP.

METHODS

This ongoing and actively enrolling multicenter observational cohort study across 32 North American pediatric cardiac centers will include at least 200 patients <21 years-old who presented ≤21 days from COMIRNATY® vaccination and meet the Centers for Disease Control and Prevention (CDC) case definition of probable or confirmed myocarditis/pericarditis or isolated pericarditis. The comparison cohort will consist of 100 patients <21 years-old with COVID-19 associated myocarditis/pericarditis, including those who meet the contemporaneous CDC case definition of multisystem inflammatory syndrome (MIS-C). The study will collect detailed hospital and follow-up data for up to 5 years following illness onset. Electrocardiograms, echocardiograms, and cardiac magnetic resonance (CMR) examinations will be interpreted in core laboratories. The primary outcomes are 1) composite of left ventricular ejection fraction <55% by echocardiogram, findings of myocarditis by original or revised Lake Louise criteria on CMR, and/or the presence of high-grade arrhythmias or conduction system disturbances at 6 months after myocarditis/pericarditis onset; 2) complications, such as death, and non-cardiac morbidities; and 3) patient-reported outcomes of global health, functional status, and quality of life. Analyses will include descriptive statistics and regression modeling.

CURRENT STATUS

Still enrolling, with 273 participants currently enrolled as of 10/16/2024 (173 vaccine-associated myocarditis/pericarditis, 100 COVID-19-associated myocarditis/pericarditis) CONCLUSIONS: With long-term follow-up and core laboratories for standardized assessments of cardiac testing, the CAMP study will make important contributions to our understanding of the mid- and long-term cardiac and non-cardiac sequelae of COVID-19 vaccine-associated myocarditis/pericarditis.

Taking ACTION to detect myocarditis related to recombinant gene transfer therapy for Duchenne Muscular Dystrophy; Consensus recommendations for cardiac surveillance

BACKGROUND

A viral vector recombinant gene transfer therapy (GTT) has recently been approved by the FDA for males of all ages with Duchenne Muscular Dystrophy (DMD) without limitations regarding preexisting cardiac impairment. Acute myocarditis is a potential life-threatening short-term complication that has been reported following GTT. This immune mediated response can range from troponin elevation to rapid cardiovascular compromise and death, particularly in those with abnormal cardiac status at baseline. Early detection of cardiac compromise is essential to optimize outcomes.

OBJECTIVES

The primary objective of this consensus statement is to advocate for caution with DMD GTT patient selection and to initiate preemptive monitoring for those who may be at increased risk for cardiac adverse events. Secondary objective is to deepen our understanding of short and long-term impact of DMD gene therapies on the heart.

METHODS

A national learning network of pediatric cardiologists with expertise in DMD developed recommendations for cardiac surveillance of DMD males receiving GTT based on available evidence and expert consensus opinion. A monitoring and treatment plan for standard and high cardiac risk patients was developed.

CONCLUSION

Partnership of cardiologists with GTT prescribers is essential to identify patient-specific considerations that might influence risk for adverse cardiac events and alter post infusion monitoring and management plans. Consistency in cardiac surveillance practices across centers will expedite our knowledge regarding potential short- and long-term cardiac effects of GTT for DMD.

Molecular imaging of cardiovascular disease: Current status and future perspective

Advancements in knowledge of cardiovascular disease, pharmacology, and chemistry have led to the development of newer radiopharmaceuticals and targets for new and more suitable molecules. Molecular imaging encompasses multiple imaging techniques for identifying the characteristics of key components involved in disease. Despite its limitations in spatial resolution, the affinity for key molecules compensates for disadvantages in diagnosing diseases and elucidating their pathophysiology. This review introduce established molecular tracers involved in clinical practice and emerging tracers already applied in clinical studies, classifying the key component in A: artery, specifically those vulnerable plaque (A-I) inflammatory cells [18F-FDG]; A-II) lipid/fatty acid; A-III) hypoxia; A-IV) angiogenesis; A-V) protease [18F/68Ga-FAPI]; A-VI) thrombus/hemorrhage; A-VII) apoptosis and A-VIII) microcalcification [18F-NaF]) and B: myocardium, including myocardial ischemia, infarction and myocardiopathy (B-I) myocardial ischemia; B-II) myocardial infarction (myocardial damage and fibrosis); B-III) myocarditis and endocarditis; B-IV) sarcoidosis; B-V) amyloidosis; B-VI) metabolism; B-VII) innervation imaging). In addition to cardiovascular-specific tracers tested in animal models, many radiotracers may have been developed in other areas, such as oncology imaging or neuroimaging. While this review does not cover all available tracers, some of them hold potential for future use assessing cardiovascular disease. Advances in molecular biology, pharmaceuticals, and imaging sciences will facilitate the identification of precise disease mechanisms, enabling precise diagnoses, better assessment of disease status, and enhanced therapeutic evaluation in this multi-modality era.

Cardiovascular complications in chronic active Epstein-Barr virus disease: a case report and literature review

Background

Cardiovascular involvement is a rare but severe complication of Epstein-Barr virus (EBV) infections. Patients with chronic active EBV (CAEBV) are at increased risk of developing cardiovascular complications and have a poor prognosis. Here, we report the rare case of a pediatric patient with CAEBV and EBV- hemophagocytic lymphohistiocytosis (HLH) complicated with a giant coronary artery aneurysm (CAA) and thrombosis, a giant Valsalva sinus aneurysm, and ascending aorta dilation seven years after the disease onset.

Case presentation

A previously healthy 3-year-old girl was initially misdiagnosed as presenting incomplete Kawasaki disease complicated by coronary artery lesions (CALs) for which she received intravenous immunoglobulin and aspirin therapy. Subsequently, she was transferred to our hospital, where we diagnosed her as having a primary EBV infection. After acyclovir therapy, her clinical symptoms resolved with negative EBV-DNA, and she was discharged home with aspirin treatment for the remaining CALs. However, she did not have regular follow-ups after that. Seven years later, the 10-year-old girl developed a prolonged fever and fatigue, and she was diagnosed as presenting CAEBV and EBV-associated hemophagocytic lymphohistiocytosis (EBV-HLH) due to the presence of a high EBV-DNA load, prolonged fever, splenomegaly, bicytopenia, hypertriglyceridemia, hypofibrinogenemia, hemophagocytosis, low NK-cell activity, and increased levels of ferritin and soluble CD25. The echocardiography images showed giant left and right coronary artery aneurysms, a giant Valsalva sinus aneurysm, and ascending aorta dilation. Her parents agreed to a therapy with intravenous immunoglobulin, methylprednisolone, antiplatelet, and anticoagulant, but not to the standard therapy of EBV-HLH. However, the cardiovascular complications, including CAAs and thrombosis, Valsalva sinus aneurysm, and aorta lesions, did not resolve. Three weeks later, the patient was finally discharged home asymptomatic. Unfortunately, one month after discharge, the fever recurred the girl. The guardian had refused treatment and took the patient home due to economic difficulties. During our subsequent follow-up visit, the girl subsequently passed away.

Conclusions

We reported the case of a pediatric patient with EBV infection who developed rare and fatal cardiovascular complications (CAAs and thrombosis, Valsalva sinus aneurysm, and aortic lesions) seven years after the onset of the infection. Clinicians should be aware of these complications during the long-term follow-up of patients with EBV infection, especially in patients with CAEBV and/or EBV-HLH.

How to behave with paediatric myocarditis: imaging methods and clinical considerations

Paediatric myocarditis is a challenging and heterogeneous condition, with varied clinical presentations ranging from mild symptoms to life-threatening complications such as heart failure, arrhythmias, and sudden cardiac death. Effective management hinges on early diagnosis, appropriate treatment, and ongoing monitoring, which can be significantly enhanced through multimodal imaging techniques. This review emphasizes the crucial role of advanced imaging in the diagnosis, prognostication, and management of paediatric myocarditis. While traditional echocardiography remains the first-line imaging tool, it is often insufficient in detecting subtle myocardial changes and it does not allow the identification of myocardial inflammation and fibrosis, particularly in cases with preserved left ventricular function. Recent advancements, including speckle-tracking echocardiography, provide enhanced sensitivity for detecting early signs of myocardial dysfunction, even in the absence of overt abnormalities. Cardiovascular magnetic resonance (CMR) has emerged as a cornerstone in the non-invasive evaluation of myocarditis, offering unparalleled tissue characterization. Indeed, CMR provides critical insights into myocardial oedema, necrosis, and fibrosis, which are essential for confirming the diagnosis, stratifying prognosis, and guiding therapy. Parametric mapping techniques allow for highly accurate detection of myocardial fibrosis (native T1 mapping) and inflammation (T2 mapping), even in the absence of gadolinium contrast, making it particularly valuable in paediatric patients. In conclusion, multimodality imaging, integrating echocardiography and CMR, allows for a comprehensive understanding of disease severity, guiding treatment decisions and optimizing long-term outcomes. This review underscores the importance of a tailored, imaging-driven approach to managing paediatric myocarditis, ensuring the best possible care for this special population.

Baseline and Follow-Up Cardiac Magnetic Resonance Imaging Findings in Children with Acute Myocarditis and Factors Associated with Late Gadolinium Enhancement

Objectives: Cardiac magnetic resonance (CMR) plays a central role in the diagnosis and follow-up of acute myocarditis (AM). In this study, we aimed to evaluate baseline and follow-up CMR findings and associated factors in children with AM. Methods: A retrospective analysis of CMR in pediatric patients with clinical presentations suggestive of myocarditis was performed. Patients' demographic characteristics, clinical data, and diagnostic test results, as well as CMR imaging results, were evaluated. Results: All 28 pediatric patients with acute myocarditis included in this study had late gadolinium enhancement (LGE) on initial CMR imaging. Additionally, 14 (50%) patients had increased extracellular volume (ECV), 4 (50%) patients had focal high-intensity areas on T2 STIR images, 15 (53.6%) patients had increased T1 relaxation time, and 17 (60.7%) patients had increased T2 relaxation time. At a median follow-up CMR of 6 months, 24 (85.7%) patients had LGE, 5 (17.9%) patients had increased ECV, and 7 (25%) patients had increased T1 relaxation time, while other parameters showed complete recovery. Baseline troponin and CRP levels, T1 relaxation time, T2 relaxation time, and increased ECV were found to be factors associated with the resolution of LGE. Conclusions: Baseline troponin and CRP levels, as well as T1 relaxation time, T2 relaxation time, and increased ECV, were effective parameters that seemed to predict the resolution of LGE. Larger and multicenter experiences would confirm these hypotheses.

Global, regional, and national burden of myocarditis in children aged 0-14 years, 1990-2021: analysis for the global burden of disease study 2021

Objective

There are limited epidemiological data on myocarditis in children aged 0-14 years. This study aims to investigate the trends in incidence, mortality, disability-adjusted life years (DALYs), and corresponding estimated annual percentage change (EAPC) of myocarditis in children aged 0-14 years from 1990 to 2021.

Methods

We utilized the 2021 Global Burden of Disease, Injuries, and Risk Factors Study (GBD) analytical tools to examine the incidence, mortality, and DALYs of myocarditis in children aged 0-14 years, considering factors such as age, sex, region, sociodemographic index (SDI), and data from 204 countries or regions.

Results

In 2021, a total of 155.45/1000 people cases of myocarditis were reported globally in children. The cases of myocarditis in children increased from 143.80/1000 people (95% uncertainty interval [UI], 93.13-214.67) in 1990 to 155.45/1000 people (95% UI, 100.31-232.31) in 2021, increasing by 8.1% (95% UI, 6.04-9.73%). Over 30 years, the global incidence rate decreased from 8.27 (95% UI, 5.35-12.34) to 7.73 (95% UI, 4.99-11.55) per 100,000 population. The myocarditis-associated mortality rate decreased from 0.36 (95% UI, 0.25-0.51) to 0.13 (95% UI, 0.10-0.16) per 100,000 population. In 2021, the highest incidence of myocarditis in children occurred in High SDI regions. Regionally, High-income Asia Pacific had the greatest increase in incidence (EAPC, 0.25; 95% CI, 0.22-0.28). Japan had the highest incidence rate of myocarditis in children, while Haiti reported the highest myocarditis-associated mortality rate and DALYs rate. Globally, environmental/occupational risk, nonoptimal temperature, high temperature, and low temperature were key risk factors for myocarditis-associated mortality in children.

Conclusion

Between 1990 and 2021, myocarditis in children saw declining mortality and DALYs but rising incidence, especially in males. Children under 1 year face higher mortality and DALY rates despite lower incidence, stressing early diagnosis. High SDI regions report higher incidence but lower mortality, while low SDI areas need standardized treatment. Japan had the highest 2021 incidence, and China had the most deaths. Underscoring the urgency for enhanced medical resources, comprehensive research into the disease's etiology, and improved prevention strategies.

Special considerations for the stabilization and resuscitation of patients with cardiac disease in the Neonatal Intensive Care Unit

Effective resuscitation of neonates with congenital heart disease (CHD) depends on comprehensive planning, thorough understanding of physiology, vigilant monitoring, and interdisciplinary collaboration to achieve the best outcomes. Neonatal heart disease can affect cardiac structure, rhythm, or ventricular function, and may be either congenital or acquired. Critical congenital heart disease (CCHD) can result in inadequate pulmonary blood flow, impaired intracardiac mixing, airway obstruction, or insufficient cardiac output. Tailored resuscitation strategies are important as early as the delivery room, where some CHD lesions may cause immediate cardiovascular instability during the transition from fetal to postnatal circulation. Premature infants with CHD are at higher risk due to their small size and the complications associated with prematurity, affecting both CHD management and overall clinical stability. Addressing both cardiac and non-cardiac causes of decompensation requires a precise understanding of each patient's unique physiology and trajectory from delivery through postintervention intensive care.

Clinical impact of novel cardiovascular magnetic resonance technology on patients with congenital heart disease: a scientific statement of the Association for European Pediatric and Congenital Cardiology and the European Association of Cardiovascular Imaging of the European Society of Cardiology

Cardiovascular magnetic resonance (CMR) imaging is recommended in patients with congenital heart disease (CHD) in clinical practice guidelines as the imaging standard for a large variety of diseases. As CMR is evolving, novel techniques are becoming available. Some of them are already used clinically, whereas others still need further evaluation. In this statement, the authors give an overview of relevant new CMR techniques for the assessment of CHD. Studies with reference values for these new techniques are listed in the Supplementary data online, supplement.

Outbreak of Acute Fulminant Myocarditis in Children in Campania Region, Italy: A Case Series

Acute fulminant myocarditis is a rare event in children, accounting for about 10% of all cases of acute myocarditis. Its lack of specific onset patterns and unpredictable evolution make diagnosis and prompt treatment challenging. We observed six cases of fulminant myocarditis admitted to our Pediatric Emergency Unit (Campania region, Sothern Italy) within a very short timeframe (50 days, from July to September 2024). Three of them died, and two are still under treatment in a Pediatric Cardiologic Intensive Care Unit in critical condition. In only one case, cardiac function improved. The described cases were not geographically linked, belonging to different areas of Southern Italy. No common etiological agent was found. Given the relatively low incidence of the condition, the occurrence of six pediatric myocarditis within approximately two months should be considered exceptional. Careful monitoring of further cases in the next few months should be warranted.

Myocardial Recovery After Corticosteroid Therapy in a Rheumatic Myopericarditis Pediatric Patient

In an endemic region for acute rheumatic fever, the suspicion of myocarditis origin had also to be directed into rheumatic etiology. We present a case of a 10-year-old patient with subacute fever and myocardial systolic dysfunction (ejection fraction: 25%). One week after treatment, recovery of systolic function was observed.

Advances in pediatrics in 2023: choices in allergy, analgesia, cardiology, endocrinology, gastroenterology, genetics, global health, hematology, infectious diseases, neonatology, neurology, pulmonology

In the last year, there have been many remarkable articles published in the Italian Journal of Pediatrics. This review highlights papers that can be potentially helpful in healthcare practice among the most cited or accessed papers on the journal website. We have chosen key articles on allergy, analgesics, cardiology, endocrinology, gastroenterology, genetics, global health, infectious diseases, neonatology, neurology and pulmonology. Advances in understanding risk factors, mechanisms, diagnosis, treatment options and prevention of pediatric diseases have been discussed and in the context of the subsequent steps. We think that progresses achieved in 2023 will have a significant impact on the management of diseases in childhood.

Rhinovirus infection presenting with acute myocarditis with complete heart block in a child: a case report

This report outlines a 9-year-old Thai boy with acute myocarditis due to rhinovirus infection, manifesting complete heart block. Despite aggressive treatment, including pulse methylprednisolone and temporary pacing, his condition remained unstable. He gradually improved over five days in the paediatric cardiac ICU and continued recovery over six months. This underscores the need for comprehensive treatment and follow-up in paediatric myocarditis.

Outbreak of paediatric myocarditis associated with parvovirus B19 infection in Italy, January to October 2024

Acute myocarditis has risen among paediatric patients in Italy, with 65 clinically suspected cases reported by 12 centres in 2024, 32 linked to parvovirus B19 (B19V) infection. In 11 cases, B19V was not ruled out despite a concurrent European outbreak. Twenty-nine children required intensive care; eight fatalities occurred. While effective for both severe B19V infection and myocarditis, intravenous immunoglobulins were given in only one-third of cases. These findings highlight the need for timely diagnosis, stronger surveillance, and standardised treatment protocols.

Older Age as a Predictor of Ongoing Active Changes in Follow-Up Cardiac Magnetic Resonance in Children with Acute Myocarditis

Background/Objectives: Cardiac magnetic resonance (CMR) is used to diagnose and monitor the course of acute myocarditis in adults and children. This study aimed to assess the frequency of persistent inflammation at follow-up CMR and to look for predictors of ongoing active changes in CMR in children with myocarditis. Methods: This retrospective study included 31 children (median age 15 years, 68% male) with clinically and CMR-diagnosed acute myocarditis who underwent baseline and follow-up CMR at a median of 6 months. Old and new Lake Louise criteria were compared. Results: A complete resolution of changes was observed in four patients (13%) at follow-up, according to both criteria. Seven patients (23%) presented ongoing active changes, and twenty (64%) showed a persistent scar according to the old Lake Louise criteria. When the new Lake Louise criteria were used, an additional two patients (6%) were found to have persistent active changes instead of a persistent scar. Patients with persistent inflammation (nine patients, 29%) were older than those who showed recovery. None of the patients below 14 years of age presented active changes on their follow-up CMR and all the patients who showed inflammation were between 14 and 17 years old. Conclusions: Pediatric myocarditis can lead to persistent active changes in CMR beyond a 6-month follow-up in over a fifth of patients. The application of new Lake Louise criteria further increases that number compared to the old criteria. The only predictor of persistent inflammatory changes in CMR is older age.

2D speckle tracking echocardiography and comparison with cardiac magnetic resonance in children with acute myocarditis

Background

Cardiac magnetic resonance (CMR) plays a major diagnostic role in acute myocarditis (AM) in children as biopsy is rarely performed in this age group. Contribution of standard echocardiography (ECHO) is limited in AM, but speckle tracking echocardiography (STE) quantitatively characterizes myocardial function, with good sensitivity for detecting subclinical left ventricular (LV) dysfunction and regional kinetics disorders beyond the site of inflammation. This work aimed to evaluate the diagnostic potential of STE as compared with CMR findings in pediatric patients with AM.

Methods

The study was conducted during 2022-2023. Troponin, electrocardiography, ECHO with STE, and CMR with early and late enhancement were performed on each patient. Affected heart segments were analyzed by both STE and CMR, and the correlation of the two methods was assessed.

Results

During the study period, 20 children were diagnosed with AM [14 boys, 6 girls; mean age 12 years (median 14)]. On ECHO, three patients had a deviation in LV biometry, and four patients had a mild systolic function disorder. STE showed at least one affected cardiac segment in all patients, most often the inferolateral segment (16/20; 80%). Of the 20 patients, STE showed a reduction in LV global longitudinal strain in 13 (65%) patients. In all patients, CMR identified an inflammatory focus, most frequently inferolateral (15/20; 75%). The strongest accordance between STE and CMR was observed for the involvement of anterolateral segments (k = 0.88) and the weakest for inferoseptal damage (k = 0.4).

Conclusions

STE can provide important diagnostic information in pediatric patients with AM. This modality supports the detection of early regional edema and subclinical myocardial dysfunction and can determine the impairment severity. STE is non-invasive and repeatable without the need for special patient preparation or for general anesthesia.

Immunoglobin attenuates fulminant myocarditis by inhibiting overactivated innate immune response

BACKGROUND AND PURPOSE

Fulminant myocarditis (FM) is a myocardial inflammatory disease that can result from either viral diseases or autoimmune diseases. In this study, we have determined the treatment effects of immunomodulatory drugs on FM.

EXPERIMENTAL APPROACH

FM was induced in A/JGpt mice by intraperitoneal administration of coxsackievirus B3, after which immunoglobins were administered daily by intraperitoneal injection. On the seventh day, the cardiac structure and function were determined using echocardiography and cardiac catheterisation. Single-cell RNA sequencing (scRNA-seq) was performed to evaluate CD45+ cells in the heart.

KEY RESULTS

Immunoglobin, a typical immunomodulatory drug, dramatically reduced mortality and significantly improved cardiac function in mice with FM. ScRNA-seq revealed that immunoglobin treatment effectively modulated cardiac immune homeostasis, particularly by attenuating overactivated innate immune responses. At the cellular level, immunoglobin predominantly targeted Plac8+ monocytes and S100a8+ neutrophils, suppressing their proinflammatory activities, and enhancing antigen processing and presentation capabilities, thereby amplifying the efficiency and potency of the immune response against the virus. Immunoglobin benefits are mediated by the modulation of multiple signalling pathways, including relevant receptors on immune cells, direction of inflammatory cell chemotaxis, antigen presentation and anti-viral effects. Subsequently, Bst2-ILT7 ligand-receptor-mediated cellular interactions manipulated by immunoglobin were further confirmed in vivo.

CONCLUSIONS AND IMPLICATIONS

Immunoglobin treatment significantly attenuated FM-induced cardiac inflammation and improved cardiac function by inhibiting overactivated innate immune responses.

Prognostic Value of Speckle Tracking Echocardiography-Derived Strain in Unmasking Risk for Arrhythmias in Children with Myocarditis

Background/Objectives: Risk assessment in pediatric myocarditis is challenging, particularly when left ventricular ejection fraction (LVEF) is preserved. This study aimed to evaluate LV myocardial deformation using speckle-tracking echocardiography (STE)-derived longitudinal +strain (LS) and assessed its diagnostic and prognostic value in children with myocarditis. Methods: Retrospective STE-derived layer-specific LV LS analysis was performed on echocardiograms from patients within the multicenter, prospective registry for pediatric myocarditis "MYKKE". Age- and sex-adjusted logistic regression and ROC analysis identified predictors of cardiac arrhythmias (ventricular tachycardia, ventricular fibrillation, atrioventricular blockage III°) and major adverse cardiac events (MACE: need for mechanical circulatory support (MCS), cardiac transplantation, and/or cardiac death). Results: Echocardiograms from 175 patients (median age 15 years, IQR 7.9-16.5 years; 70% male) across 13 centers were included. Cardiac arrhythmias occurred in 36 patients (21%), and MACE in 28 patients (16%). Impaired LV LS strongly correlated with reduced LVEF (r > 0.8). Impaired layer-specific LV LS, reduced LVEF, LV dilatation, and increased BSA-indexed LV mass, were associated with the occurrence of MACE and cardiac arrhythmias. In patients with preserved LVEF, LV LS alone predicted cardiac arrhythmias (p < 0.001), with optimal cutoff values of -18.0% for endocardial LV LS (sensitivity 0.69, specificity 0.94) and -17.0% for midmyocardial LV LS (sensitivity 0.81, specificity 0.75). Conclusions: In pediatric myocarditis, STE-derived LV LS is not only a valuable tool for assessing systolic myocardial dysfunction and predicting MACE but also identifies patients at risk for cardiac arrhythmias, even in the context of preserved LVEF.

Identifying Post-Acute Sequelae of SARS-CoV-2 Among Children in New York State Medicaid Managed Care

Persons who contract COVID-19 are at risk of developing post-acute sequelae of SARS-CoV-2 (PASC). The objective of this study was to describe the incidence of PASC in a pediatric Medicaid population. Using a retrospective cohort of children enrolled in New York State Medicaid Managed Care we compared incident diagnoses between children with a positive laboratory test for SARS-CoV-2 in 2021 to children without a positive test in 2021 and children with a viral respiratory diagnosis in 2019. Logistic regression models estimated adjusted odds ratios using the Cohen's d statistic to assess the strength of associations. Most unadjusted incidence of clinical outcomes were less than 1% for all cohorts. Relative to the 2021 comparison cohort, significant increases among SARS-CoV-2 cases were observed in sequela of infectious disease conditions, general signs and symptoms, and pericarditis and pericardial disease and for the 2019 comparison, sequela of infectious disease conditions and suicidal ideation. However, associations were mostly determined to be weak or marginal. In this low socioeconomic status pediatric population, incidence of new clinical sequelae was low with mostly weak or marginal increases associated with SARS-CoV-2 infection. Though the incidence was low, some outcomes may be severe. Observed associations may have been impacted by pandemic behavior modification including social distancing policies.

Cardiac manifestations and outcomes of COVID-19 vaccine-associated myocarditis in the young in the USA: longitudinal results from the Myocarditis After COVID Vaccination (MACiV) multicenter study

Background

We aimed to study the clinical characteristics, myocardial injury, and longitudinal outcomes of COVID-19 vaccine-associated myocarditis (C-VAM).

Methods

In this longitudinal retrospective observational cohort multicenter study across 38 hospitals in the United States, 333 patients with C-VAM were compared with 100 patients with multisystem inflammatory syndrome in children (MIS-C). We included patients ≤30 years of age with a clinical diagnosis of acute myocarditis after COVID-19 vaccination based on clinical presentation, abnormal biomarkers and/or cardiovascular imaging findings. Demographics, past medical history, hospital course, biochemistry results, cardiovascular imaging, and follow-up information from April 2021 to November 2022 were collected. The primary outcome was presence of myocardial injury as evidenced by late gadolinium enhancement (LGE) on cardiac magnetic resonance (CMR) imaging.

Findings

Patients with C-VAM were predominantly white (67%) adolescent males (91%, 15.7 ± 2.8 years). Their initial clinical course was more likely to be mild (80% vs. 23%, p < 0.001) and cardiac dysfunction was less common (17% vs. 68%, p < 0.0001), compared to MIS-C. In contrast, LGE on CMR was more prevalent in C-VAM (82% vs. 16%, p < 0.001). The probability of LGE was higher in males (OR 3.28 [95% CI: 0.99, 10.6, p = 0.052]), in older patients (>15 years, OR 2.74 [95% CI: 1.28, 5.83, p = 0.009]) and when C-VAM occurred after the first or second dose as compared to the third dose of mRNA vaccine. Mid-term clinical outcomes of C-VAM at a median follow-up of 178 days (IQR 114-285 days) were reassuring. No cardiac deaths or heart transplantations were reported until the time of submission of this report. LGE persisted in 60% of the patients at follow up.

Interpretation

Myocardial injury at initial presentation and its persistence at follow up, despite a mild initial course and favorable mid-term clinical outcome, warrants continued clinical surveillance and long-term studies in affected patients with C-VAM.

Funding

The U.S. Food and Drug Administration.

Multiparametric Cardiac Magnetic Resonance Imaging to Discriminate Endomyocardial Biopsy-Proven Chronic Myocarditis From Healed Myocarditis

BACKGROUND

Detecting ongoing inflammation in myocarditis patients has prognostic relevance, but there are limited data on the detection of chronic myocarditis and its differentiation from healed myocarditis.

OBJECTIVES

This study sought to assess the performance of cardiac magnetic resonance (CMR) for the detection of ongoing inflammation and the discrimination of chronic myocarditis from healed myocarditis.

METHODS

Consecutive patients with persistent symptoms (>30 days) suggestive of myocarditis were prospectively enrolled from a single tertiary center. All patients underwent a multiparametric 1.5-T CMR protocol including biventricular strain, T1/T2 mapping, and late gadolinium enhancement (LGE). Endomyocardial biopsy was chosen for the reference standard diagnosis.

RESULTS

Among 452 consecutive patients, 103 (median age: 50 years; 66 men) had evaluable CMR and cardiopathologic reference diagnosis: 53 (51%) with chronic lymphocytic myocarditis and 50 (49%) with healed myocarditis. T2 mapping as a single parameter showed the best accuracy in detecting chronic myocarditis, if abnormal in ≥3 segments (92%; 95% CI: 85-97), and provided the best discrimination from healed myocarditis, as defined by the area under the receiver-operating characteristic curve (0.87 [95% CI: 0.79-0.93]; P < 0.001), followed by radial peak systolic strain rate of the left ventricle (0.86) and the right ventricle (0.84); T1 mapping (0.64), extracellular volume fraction (0.62), and LGE (0.57). Specificity increased when T2 mapping was combined with elevation of either troponin or C-reactive protein.

CONCLUSIONS

A multiparametric CMR protocol allows detection of ongoing myocardial inflammation and discrimination of chronic myocarditis from healed myocarditis, with segmental T2 mapping and biventricular strain analysis showing higher diagnostic accuracy compared with T1 mapping, extracellular volume fraction, and LGE. The use of biomarkers (troponin or C-reactive protein) may improve specificity.

Febrile young infants and the association with enterovirus infection

BACKGROUND

Enterovirus is a common pediatric infectious disease, but the epidemiological data in young infants were lacking. This study aims to evaluate the role of enterovirus in febrile young infants and identify risk factors for severe infections.

METHODS

We enrolled febrile infants younger than 90 days admitted to National Taiwan University Hospital from January 2010 to June 2021. Enterovirus infection was confirmed via viral isolation or pan-enterovirus PCR. Central nervous system involvement was defined by positive culture or PCR in cerebrospinal fluid. Severe complications included sepsis, hepatic failure, myocarditis, shock, encephalitis, acute kidney injury, respiratory failure, and multiorgan failure.

RESULTS

Out of 840 febrile infants, 17.4% (n = 146) had enterovirus infection. Among these, 46% (n = 67) presented with meningitis and/or encephalitis. Early-onset enterovirus infection within the first two weeks of life was significantly linked to increased risks of anemia (hemoglobin <9 g/dL), ICU admission, central nervous system involvement, shock, hepatic failure, and mortality. Multivariable logistic regression identified high-risk serotypes (aOR 17.4, [95% CI 1.58, 191.5], p = 0.019) and hemoglobin <9 g/dL (aOR 44.9, [95% CI 5.6, 357.6], p < 0.001) as significant risk factors for severe complications.

CONCLUSIONS

Enterovirus accounted for 17.4% of the etiology in febrile young infants and the case-fatality rate was 2%. Febrile young infants who had risk factors of enterovirus infection should consider viral culture or PCR examination for confirmation.

Practice patterns of cardiovascular magnetic resonance use in the diagnosis of pediatric myocarditis: A survey-based study

BACKGROUND

Cardiovascular magnetic resonance (CMR) is used to diagnose myocarditis in adults and children based on the original Lake Louise criteria (LLC) and more recently the revised LLC. The major change included in the revised LLC was the incorporation of parametric mapping, which significantly increases the sensitivity and specificity of diagnosis. Subsequently, scientific statements have recommended the use of parametric mapping in the diagnosis of myocarditis in children. However, there are some challenges to parametric mapping that are unique to the pediatric population. Our goal is to characterize clinical CMR and parametric mapping practice patterns for the diagnosis of myocarditis in pediatric centers.

METHODS

The Cardiovascular Magnetic Resonance Evaluation in Return to Athletes for Myocarditis in Coronavirus Disease 2019 and Immunization Consortium (CERAMICi) created a Research Electronic Data Capture (REDCap) survey to evaluate clinical practice patterns for diagnosis of myocarditis in pediatrics. This survey was distributed to the Society for Cardiovascular Magnetic Resonance community.

RESULTS

Fifty-nine responses from 51 centers were received, with only one response from each center being utilized. Only 35% (18/51) of centers (37% (14/38) North America, 31% (4/13) international) reported using CMR routinely in all patients with a suspicion of myocarditis. Diagnostic uncertainty was noted as the most important reason for CMR, while cost was noted as the least important consideration. The majority of centers reported using the revised LLC (37/51, 72%) compared to original LLC (7/51, 14%) or a hybrid criteria (6/51, 12%). When looking at the use of parametric mapping, only 5/47 (11%) for T1 mapping and 11/49 (22%) for T2 mapping reported having scanner-specific pediatric normative data.

CONCLUSION

Routine CMR imaging for diagnosis of myocarditis in pediatrics is infrequently performed at surveyed centers despite the focus on a group of non-invasive cardiac imagers. While the majority reported using parametric mapping, few centers reported having pediatric scanner-specific normative data. This highlights an important gap in the utilization of CMR that may aid in the diagnosis of myocardial disease.

Case Report: Acute myocarditis in a patient with Duchenne muscular dystrophy

Background

Cardiovascular complications are the leading cause of death among individuals with Duchenne muscular dystrophy (DMD). However, due to the difficulty in evaluating individuals with inactive DMD, acute myocardial injury may be overlooked.

Case presentation

An 11-year-old boy with DMD presented to the emergency department with a 5-day history of persistent nasal congestion, runny nose, and cough. He was regularly taking prednisolone acetate, angiotensin-converting enzyme (ACE) inhibitors, and β-blockers for suspected DMD-associated cardiomyopathy. Upon presentation, a substantially elevated cardiac troponin I (cTnI) level of 19.8 μg/L and abnormal electrocardiogram (ECG) results were detected. Further cardiac magnetic resonance imaging (CMR) showed myocardial inflammation with localized T2 hyperintensity from the basal to middle lateral and inferior walls, as well as late gadolinium enhancement (LGE) from the basal to apical inferior lateral walls, supporting a diagnosis of acute myocarditis. Subsequently, the patient showed clinical improvement in response to combination treatment with intravenous immunoglobulin, oral prednisolone acetate, potassium chloride sustained-release tablets, anti-heart failure medication, and broad-spectrum antibiotics.

Conclusions

We report a rare case of acute myocarditis in a patient with DMD, potentially due to upper respiratory tract infection. This case highlights the importance of early myocarditis recognition and treatment in patients with DMD.

Global burden of myocarditis in youth and middle age (1990-2019): A systematic analysis of the disease burden and thirty-year forecast

BACKGROUND

Myocarditis is increasingly recognized as a critical health issue, particularly among youth and middle-aged populations. This study aims to analyze the global burden and trends of myocarditis in these age groups to emphasize the need for region-specific prevention and treatment strategies.

METHODS

Using data from the Global Burden of Disease (GBD) study (1990-2019), we evaluated the age-standardized rates (ASR) of myocarditis in individuals aged 10 to 54 years. We calculated average annual percentage changes (AAPC) and estimated annual percentage changes (EAPC). Additionally, we examined the correlation between myocarditis incidence and the Human Development Index (HDI) and Socio-demographic Index (SDI). Age and sex trends in myocarditis were analyzed, and Bayesian age-period-cohort (BAPC) models were used to forecast prevalence trends up to 2050.

RESULTS

The High-income Asia Pacific region had the highest ASR of myocarditis, while North Africa and the Middle East had the lowest. North Africa and the Middle East also experienced the fastest average annual growth in ASR, whereas High-income North America saw the most significant decline. Correlational analysis showed that countries with a high SDI exhibited higher myocarditis ASR. The burden of myocarditis was greater among males than females, with this disparity increasing with age. Projections indicate a stable trend in the incidence of myocarditis among the youth and middle-aged population up to 2050, although the total number of cases is expected to rise.

CONCLUSION

Our study reveals a significant upward trend in myocarditis among youth and middle-aged populations, highlighting the urgency for early monitoring and preventative strategies.

Association Between High-Sensitivity Troponin (hs-cTnT) and Diagnosis of Myocarditis in Previously Healthy Pediatric Patients

Cardiac troponin is commonly used to screen for cardiac diagnoses in pediatric patients, as it is only released by myocardial tissue. There is limited data regarding high-sensitivity troponin T in pediatric populations and its clinical interpretation. We sought to determine how high-sensitivity troponin values are associated with myocarditis diagnosis. High sensitivity troponin levels were reviewed for pediatric patients at our center from February 2022 to February 2023. Basic demographic and presenting data (including age, gender, body mass index), and diagnoses (cardiac diagnosis, including myocarditis, vs non-cardiac) were compared for patients with elevated initial troponin levels (≥ 12 ng/L) vs. those with non-elevated values. Of the 308 patients included, 91 (29.5%) had elevated hs-cTnT and 45 (14.6%) had a cardiac diagnosis, of whom 8 (2.5%) were ultimately diagnosed with acute myocarditis. There was no meaningful difference in demographic characteristics between the elevated and non-elevated hs-cTnT groups. For patients with diagnosis of myocarditis (n = 8), median peak levels were 506.5 ng/L (182.0 to 1184.0) versus 6.0 ng/L (< 6.0 to 13.5) for those with all other diagnoses (n = 300) (p < 0.001). A high sensitivity troponin cut-off value of 90 ng/dL was established for diagnosis of myocarditis, providing high sensitivity (100%) and specificity of (95%).

Cancer-Induced Resting Sinus Tachycardia: An Overlooked Clinical Diagnosis

Elevated resting heart rate is frequently observed in cancer patients, and is associated with increased mortality. Although specific chemotherapeutic agents can induce cardiotoxicity, the presence of sinus tachycardia in chemotherapy-naive patients suggests other factors likely contribute to this clinical presentation. Despite its prevalence, cancer-associated resting sinus tachycardia has not been fully recognized and comprehensively described as a separate clinical entity. Secondary effects of cancer, especially structural cardiac changes, secretory factors (inflammatory cytokines), and thromboembolic disease can cause resting tachycardia. Alternatively, rapid heart rate may reflect compensatory mechanisms responding to increased metabolic demands, raised cardiac output states, and even pain. Hence, cancer-associated tachycardia presents a clinical dilemma; acute life-threatening conditions (such as sepsis, pulmonary embolism, etc.) must be ruled out, but cancer itself can explain resting sinus tachycardia and more conservative management can avoid unnecessary testing, cost and patient stress. Furthermore, identification and management of cardiac conditions associated with cancer may improve survival and the quality of life of cancer patients.

Campylobacter-Associated Myocarditis in a 17-Year-Old Male

Chest pain is a common presenting complaint in adolescent patients. Myocarditis is an important and potentially serious etiology of chest pain for clinicians who care for these patients to recognize. Myocarditis is commonly virally mediated, while extra-intestinal cardiac manifestations of bacterial enteritis, such as Campylobacter infections,are rare. Awareness of this uncommon, but potentially life-threatening pathophysiology is important for clinicians to understand.  In our case, a 17-year-old male presented with chest discomfort, chest pain on inspiration, headache, myalgias, vomiting, and diarrhea. He denied recent viral illnesses or immunizations. He lived in rural Ohio, swam recently in a freshwater lake, and had eaten home-prepared deer meat. His father had diarrhea as well. Presenting vital signs were within normal limits for age. The patient was obese (BMI 48.5), with an otherwise normal physical exam, including a thorough cardiopulmonary assessment. Laboratory workup revealed leukocytosis (16.1 x 109/L) and elevated high-sensitivity troponin (15,857 ng/L, >22,000 ng/L three hours later, ref range <20). Gastrointestinal polymerase chain reaction (PCR) panel detected Campylobacter spp., and stool culture was positive for Campylobacter jejuni. ECG, echocardiography, chest X-ray, and CT angiography were normal. Cardiac MRI revealed an increased T2 signal consistent with myocarditis. The patient was treated with non-steroidal anti-inflammatory drugs (NSAIDs) and azithromycin and had complete resolution in symptoms. He was exercise-restricted for six months.  Myocarditis is a potentially fatal pathology, representing a significant cause of sudden death in young adults. Myocarditis can present with a broad spectrum of signs and symptoms as well as variable clinical severity. Bacterial causes of myocarditis are uncommon, with Campylobacter among the least common. Campylobacter gastroenteritis, however, is quite common worldwide. Extra-intestinal and cardiac manifestations are rare; thus, it is important to maintain a high index of suspicion. Due in part to its rarity, treatment for Campylobacter-associated myocarditis is not well established. Treatment for myocarditis, regardless of etiology, is largely supportive in nature. Campylobacter-directed antibiotics, such as azithromycin, have been used successfully in adolescents with Campylobacter-associated myocarditis. Non-steroidal anti-inflammatory drugs (NSAIDs) are frequently used for symptom control, though their use remains controversial. Activity restriction is recommended for six months to reduce the risk of sudden cardiac death.  Myocarditis is an important cause of sudden death in young adults and is a rare extra-intestinal manifestation of Campylobacter bacterial gastroenteritis. Pediatric and adult providers should be aware of this presentation and its pathophysiology. They should also utilize a multi-modal workup, aggressive supportive care, appropriate subspecialty consultation, and appropriate antibiotics for patients with diarrheal illness and a high clinical suspicion for extra-intestinal involvement, such as myocarditis.

Myocarditis in children 2024, new themes and continued questions

PURPOSE OF REVIEW

While pediatric myocarditis incidence has increased since the coronavirus disease 2019 (COVID-19) pandemic, there remain questions regarding diagnosis, risk stratification, and optimal therapy. This review highlights recent publications and continued unanswered questions related to myocarditis in children.

RECENT FINDINGS

Emergence from the COVID-19 era has allowed more accurate description of the incidence and prognosis of myocarditis adjacent to COVID-19 infection and vaccine administration as well that of multi-system inflammatory disease in children (MIS-C). As cardiac magnetic resonance technology has shown increased availability and evidence in pediatric myocarditis, it is important to understand conclusions from adult imaging studies and define the use of this imaging biomarker in children. Precision medicine has begun to allow real-time molecular evaluations to help diagnose and risk-stratify cardiovascular diseases, with emerging evidence of these modalities in myocarditis.

SUMMARY

Recent information regarding COVID-19 associated myocarditis, cardiac magnetic resonance, and molecular biomarkers may help clinicians caring for children with myocarditis and identify needs for future investigations.

Pediatric dilated cardiomyopathy: a review of current clinical approaches and pathogenesis

Pediatric dilated cardiomyopathy (DCM) is a rare, yet life-threatening cardiovascular condition characterized by systolic dysfunction with biventricular dilatation and reduced myocardial contractility. Therapeutic options are limited with nearly 40% of children undergoing heart transplant or death within 2 years of diagnosis. Pediatric patients are currently diagnosed based on correlating the clinical picture with echocardiographic findings. Patient age, etiology of disease, and parameters of cardiac function significantly impact prognosis. Treatments for pediatric DCM aim to ameliorate symptoms, reduce progression of disease, and prevent life-threatening arrhythmias. Many therapeutic agents with known efficacy in adults lack the same evidence in children. Unlike adult DCM, the pathogenesis of pediatric DCM is not well understood as approximately two thirds of cases are classified as idiopathic disease. Children experience unique gene expression changes and molecular pathway activation in response to DCM. Studies have pointed to a significant genetic component in pediatric DCM, with variants in genes related to sarcomere and cytoskeleton structure implicated. In this regard, pediatric DCM can be considered pediatric manifestations of inherited cardiomyopathy syndromes. Yet exciting recent studies in infantile DCM suggest that this subset has a distinct etiology involving defective postnatal cardiac maturation, such as the failure of programmed centrosome breakdown in cardiomyocytes. Improved knowledge of pathogenesis is central to developing child-specific treatment approaches. This review aims to discuss the established biological pathogenesis of pediatric DCM, current clinical guidelines, and promising therapeutic avenues, highlighting differences from adult disease. The overarching goal is to unravel the complexities surrounding this condition to facilitate the advancement of novel therapeutic interventions and improve prognosis and overall quality of life for pediatric patients affected by DCM.

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.

Rate of cardiovascular events up to 8 years after uncomplicated myocarditis: a nationwide cohort study

AIMS

While prognosis of acute myocarditis with uncomplicated presentation is perceived as benign, data on long-term outcomes are scarce. We evaluated rates of myocarditis-associated cardiovascular events after a first-time hospitalization with uncomplicated acute myocarditis in patients without known heart disease.

METHODS AND RESULTS

In this retrospective nationwide population-based cohort study from 2013 to 2020, hospitalized patients with uncomplicated acute myocarditis but without known heart disease were 1:1 propensity score-matched with surgical controls hospitalized for laparoscopic appendectomy. As assessed in time-to-event analyses, the primary outcome was a composite of rehospitalization for myocarditis, pericardial disease, heart failure and its complications, arrhythmias, implantation of cardiac devices, and heart transplant. After matching, we identified 1439 patients with uncomplicated acute myocarditis (median age of 35 years, 74.0% male) and 1439 surgical controls (median age of 36 years, 74.4% male). Over a median follow-up of 39 months, compared with surgical controls, the hazard ratio for the primary composite outcome was 42.3 [95% confidence interval (CI) 17.4-102.8], corresponding to an incidence rate of 43.7 vs. 0.9 per 1000 patient-years (py) and an incidence rate difference of 42.7 (95% CI 36.7-48.8) per 1000 py.

CONCLUSION

Patients hospitalized with uncomplicated acute myocarditis and no known prior heart disease were associated with substantial risk for cardiovascular events over a follow-up of up to 8 years. This calls for a more efficient therapeutic management of this population of patients.

Infectious factors in myocarditis: a comprehensive review of common and rare pathogens

BACKGROUND

Myocarditis is a significant health threat today, with infectious agents being the most common cause. Accurate diagnosis of the etiology of infectious myocarditis is crucial for effective treatment.

MAIN BODY

Infectious myocarditis can be caused by viruses, prokaryotes, parasites, and fungi. Viral infections are typically the primary cause. However, some rare opportunistic pathogens can also damage heart muscle cells in patients with immunodeficiencies, neoplasms and those who have undergone heart surgery.

CONCLUSIONS

This article reviews research on common and rare pathogens of infectious myocarditis, emphasizing the complexity of its etiology, with the aim of helping clinicians make an accurate diagnosis of infectious myocarditis.

V-A ECMO for neonatal coxsackievirus B fulminant myocarditis: a case report and literature review

Background

Neonatal (enteroviral) myocarditis (NM/NEM) is rare but unpredictable and devastating, with high mortality and morbidity. We report a case of neonatal coxsackievirus B (CVB) fulminant myocarditis successfully treated with veno-arterial extracorporeal membrane oxygenation (V-A ECMO).

Case presentation

A previously healthy 7-day-old boy presented with fever for 4 days. Progressive cardiac dysfunction (weak heart sounds, hepatomegaly, pulmonary edema, ascites, and oliguria), decreased left ventricular ejection fraction (LVEF) and fractional shortening (FS), transient ventricular fibrillation, dramatically elevated creatine kinase-MB (405.8 U/L), cardiac troponin I (25.85 ng/ml), and N-terminal pro-brain natriuretic peptide (NT-proBNP > 35,000 ng/L), and positive blood CVB ribonucleic acid indicated neonatal CVB fulminating myocarditis. It was refractory to mechanical ventilation, fluid resuscitation, inotropes, corticosteroids, intravenous immunoglobulin, and diuretics during the first 4 days of hospitalization (DOH 1-4). The deterioration was suppressed by V-A ECMO in the next 5 days (DOH 5-9), despite the occurrence of bilateral grade III intraventricular hemorrhage on DOH 7. Within the first 4 days after ECMO decannulation (DOH 10-13), he continued to improve with withdrawal of mechanical ventilation, LVEF > 60%, and FS > 30%. In the subsequent 4 days (DOH 14-17), his LVEF and FS decreased to 52% and 25%, and further dropped to 37%-38% and 17% over the next 2 days (DOH 18-19), respectively. There was no other deterioration except for cardiomegaly and paroxysmal tachypnea. Through strengthening fluid restriction and diuresis, and improving cardiopulmonary function, he restabilized. Finally, notwithstanding NT-proBNP elevation (>35,000 ng/L), cardiomegaly, and low LVEF (40%-44%) and FS (18%-21%) levels, he was discharged on DOH 26 with oral medications discontinued within 3 weeks postdischarge. In nearly three years of follow-up, he was uneventful, with interventricular septum hyperechogenic foci and mild mitral/tricuspid regurgitation.

Conclusions

Dynamic cardiac function monitoring via real-time echocardiography is useful for the diagnosis and treatment of NM/NEM. As a lifesaving therapy, ECMO may improve the survival rate of patients with NM/NEM. However, the "honeymoon period" after ECMO may cause the illusion of recovery. Regardless of whether the survivors of NM/NEM have undergone ECMO, close long-term follow-up is paramount to the prompt identification and intervention of abnormalities.

Abundant Neutrophil-Initiated Acute Myocardial Injury Following Coxsackievirus A6 Infection

Coxsackievirus A6 (CVA6) is currently considered as a predominant pathogen of hand, foot, and mouth disease (HFMD), and is occasionally linked to myocardial injury. We first established a mouse model of CVA6-induced myocardial injury. Next, we analyzed the immune cell phenotypes CVA6-infected mice hearts by fluorescence-activated cell sorting, and found that CVA6 led to massive neutrophils infiltration, suggesting their potential link with the occurrence of myocardial injury. We further used either αGr-1 or αLy6G antibody to deplete neutrophils, and found that neutrophil-depleted animals showed decreased cardiac enzymes, lower degree of pathology in hearts, and reduced inflammatory cytokine production compared to isotype controls. Finally, we confirmed the involvement of neutrophils in myocardial injury of clinical patients with severe HFMD. Our study suggests that excessive neutrophils contribute to myocardial injury caused by CVA6 infection, which provides new insights into myocardial injury during the development of HFMD severity and the outcome of immune cell-mediated therapies.

Soluble suppression of tumorigenicity 2 associated with major adverse cardiac events in children with myocarditis

Objective

Soluble suppression of tumorigenicity 2 (sST2) is associated with the prognosis of some cardiac diseases, but studies on sST2 and the prognosis of patients with myocarditis are rare. This study investigated the relationship between major adverse cardiovascular events (MACEs) and sST2 during hospitalization in pediatric patients with myocarditis.

Methods

This was a single-center retrospective cohort study. A total of 252 patients aged ≤14 years diagnosed with myocarditis were enrolled. Events during the hospitalization were defined as MACEs (all-cause death > new heart failure > ventricular arrhythmia).

Results

A total of 25 people had MACEs during their hospital stay. The mortality during hospitalization was 6/23 (26%) in patients with heart failure and 3/10 (30%) in patients with ventricular arrhythmias. After including these risk factors in a multivariate logistic regression analysis, NT-proBNP (OR 4.323; 95% CI, 2.433-7.679; p < 0.001) and sST2 (OR 1.020; 95% CI, 1.003-1.037; p = 0.022) remained statistically significant and were independent risk factors for MACEs during hospitalization in pediatric myocarditis patients.

Conclusions

Elevated levels of NT-proBNP and sST2 were independently associated with major adverse cardiovascular events during hospitalization in children with myocarditis, and both showed good predictive efficacy.

Application of Cardiovascular Physiology to the Critically Ill Patient

OBJECTIVES

To use the ventricular pressure-volume relationship and time-varying elastance model to provide a foundation for understanding cardiovascular physiology and pathophysiology, interpreting advanced hemodynamic monitoring, and for illustrating the physiologic basis and hemodynamic effects of therapeutic interventions. We will build on this foundation by using a cardiovascular simulator to illustrate the application of these principles in the care of patients with severe sepsis, cardiogenic shock, and acute mechanical circulatory support.

DATA SOURCES

Publications relevant to the discussion of the time-varying elastance model, cardiogenic shock, and sepsis were retrieved from MEDLINE. Supporting evidence was also retrieved from MEDLINE when indicated.

STUDY SELECTION, DATA EXTRACTION, AND SYNTHESIS

Data from relevant publications were reviewed and applied as indicated.

CONCLUSIONS

The ventricular pressure-volume relationship and time-varying elastance model provide a foundation for understanding cardiovascular physiology and pathophysiology. We have built on this foundation by using a cardiovascular simulator to illustrate the application of these important principles and have demonstrated how complex pathophysiologic abnormalities alter clinical parameters used by the clinician at the bedside.

Loss of TRIM29 mitigates viral myocarditis by attenuating PERK-driven ER stress response in male mice

Viral myocarditis, an inflammatory disease of the myocardium, is a significant cause of sudden death in children and young adults. The current coronavirus disease 19 pandemic emphasizes the need to understand the pathogenesis mechanisms and potential treatment strategies for viral myocarditis. Here, we found that TRIM29 was highly induced by cardiotropic viruses and promoted protein kinase RNA-like endoplasmic reticulum kinase (PERK)-mediated endoplasmic reticulum (ER) stress, apoptosis, and reactive oxygen species (ROS) responses that promote viral replication in cardiomyocytes in vitro. TRIM29 deficiency protected mice from viral myocarditis by promoting cardiac antiviral functions and reducing PERK-mediated inflammation and immunosuppressive monocytic myeloid-derived suppressor cells (mMDSC) in vivo. Mechanistically, TRIM29 interacted with PERK to promote SUMOylation of PERK to maintain its stability, thereby promoting PERK-mediated signaling pathways. Finally, we demonstrated that the PERK inhibitor GSK2656157 mitigated viral myocarditis by disrupting the TRIM29-PERK connection, thereby bolstering cardiac function, enhancing cardiac antiviral responses, and curbing inflammation and immunosuppressive mMDSC in vivo. Our findings offer insight into how cardiotropic viruses exploit TRIM29-regulated PERK signaling pathways to instigate viral myocarditis, suggesting that targeting the TRIM29-PERK axis could mitigate disease severity.