Diagnosis, Evaluation, and Treatment of Myocarditis in Children

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.

Effect of Yangxin Huoxue Jiedu recipe on inflammatory factors and oxidative stress on viral myocarditis in children

OBJECTIVE

This observation purposed to investigate the effect of the Yangxin Huoxue Jiedu formula on children with viral myocarditis and its effect on inflammatory factors and oxidative response.

MATERIALS AND METHODS

A total of 121 children with viral myocarditis were randomly divided into two groups, namely the control group (N = 60) and the traditional Chinese medicine group (N = 61). The control group was mainly treated with routine therapy, while the traditional Chinese medicine group was treated with Yangxin Huoxue Jiedu recipes based on the control group. The creatine kinase, creatine kinase myocardial isoenzyme, aspartate aminotransferase, lactic dehydrogenase, hydroxybutyrate dehydrogenase, cardiac troponin I, brain natriuretic peptide, interleukin-6, interleukin-8, and tumour necrosis factor-alpha, superoxide dismutase and malondialdehyde in viral myocarditis patients were tested to estimate the myocardial function, inflammation, and oxidative situation.

RESULTS

After Yangxin Huoxue Jiedu treatment, 15 cases were recovered, 20 were excellent, and 21 were effective, which had a significant difference from the control group. The concentration of creatine kinase, creatine kinase myocardial isoenzyme, aspartate aminotransferase, lactic dehydrogenase, hydroxybutyrate dehydrogenase, cardiac troponin I and brain natriuretic peptide was decreased in the traditional Chinese medicine group. The levels of interleukin-6, interleukin-8, and tumour necrosis factor-alpha in the traditional Chinese medicine group were significantly lower than those in the control group. Superoxide dismutase was higher and malondialdehyde was lower than those in the control group.

CONCLUSION

The use of Yangxin Huoxue Jiedu in the treatment of viral myocarditis has a definite clinical effect, which could improve myocardial function, reduce body inflammation, and promote oxidative recovery.

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.

Echocardiographic function evaluation in adolescents following BNT162b2 Pfizer-BioNTech mRNA vaccination: A preliminary prospective study

BACKGROUND

Vaccination against coronavirus disease 2019 (COVID-19) is crucial for preventing and minimizing illness. Myocarditis and pericarditis after messenger RNA (mRNA) COVID-19 vaccination in adolescents and young adult males have been reported. Most of the studies in this area rely on retrospective symptom reporting, especially for adolescents experiencing myocarditis as a potential side effect. However, prospective postvaccination echocardiographic evaluation is rare.

METHODS

The study enrolled adolescents aged 12 to 15 years who received the second dose of the BNT162b2 Pfizer-BioNTech mRNA (BNT) vaccine. Serial echocardiographic examinations were conducted at baseline before vaccination, followed by subsequent assessments on days 2, 7, 14, and 28 to identify any notable differences or abnormal changes in cardiac function. Clinical symptom assessments were also recorded during each follow-up.

RESULTS

The study included 25 adolescents, comprising 14 males and 11 females, who completed the four follow-ups. Their mean age was 14 ± 1 years. The average interval between the first and second BNT vaccine doses was 90 ± 7 days. Ejection fraction values were 73.8% ± 5.2% at baseline, followed by 75.7% ± 5.3%, 75.5% ± 4.6%, 75.7% ± 4.5%, and 77.8% ± 5.8% at day 2, 7, 14, and 28, respectively. The cardiac function remained stable across all time points, with no significant differences observed between male and female participants. Within postvaccination 48 hours, 18 (72%) of the enrolled adolescents experienced temporary discomfort symptoms, which completely resolved by the final follow-up on the 28th day after vaccination.

CONCLUSION

Although adolescents vaccinated with the second dose of BNT vaccine commonly experienced transient postvaccination discomfort, the serial echocardiographic examinations did not reveal any significant deterioration of cardiac function within 28 days. Further studies are required to investigate the incidence of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) mRNA vaccination-associated myocarditis in adolescents and the related mechanisms.

Clinical course and follow-up of pediatric patients with COVID-19 vaccine-associated myocarditis compared to non-vaccine-associated myocarditis within the prospective multicenter registry-"MYKKE"

BACKGROUND

Since the onset of widespread COVID-19 vaccination, increased incidence of COVID-19 vaccine-associated myocarditis (VA-myocarditis) has been noted, particularly in male adolescents.

METHODS

Patients <18 years with suspected myocarditis following COVID-19 vaccination within 21 days were enrolled in the PedMYCVAC cohort, a substudy within the prospective multicenter registry for pediatric myocarditis "MYKKE." Clinical data at initial admission, 3- and 9-months follow-up were monitored and compared to pediatric patients with confirmed non-vaccine-associated myocarditis (NVA-myocarditis) adjusting for various baseline characteristics.

RESULTS

From July 2021 to December 2022, 56 patients with VA-myocarditis across 15 centers were enrolled (median age 16.3 years, 91% male). Initially, 11 patients (20%) had mildly reduced left ventricular ejection fraction (LVEF; 45%-54%). No incidents of severe heart failure, transplantation or death were observed. Of 49 patients at 3-months follow-up (median (IQR) 94 (63-118) days), residual symptoms were registered in 14 patients (29%), most commonly atypical intermittent chest pain and fatigue. Diagnostic abnormalities remained in 23 patients (47%). Of 21 patients at 9-months follow-up (259 (218-319) days), all were free of symptoms and diagnostic abnormalities remained in 9 patients (43%). These residuals were mostly residual late gadolinium enhancement in magnetic resonance imaging. Patients with NVA-myocarditis (n=108) more often had symptoms of heart failure (P = .003), arrhythmias (P = .031), left ventricular dilatation (P = .045), lower LVEF (P < .001) and major cardiac adverse events (P = .102).

CONCLUSIONS

Course of COVID-19 vaccine-associated myocarditis in pediatric patients seems to be mild and differs from non-vaccine-associated myocarditis. Due to a considerable number of residual symptoms and diagnostic abnormalities at follow-up, further studies are needed to define its long-term implications.

Establishment and validation of a prediction model for myocarditis in Chinese children below 14 years old: a protocol for a retrospective cohort study

INTRODUCTION

Paediatric myocarditis, a rare inflammatory disease, often presents without clear early symptoms. Although cardiac troponin I levels can aid in diagnosing myocarditis, they are not definitive indicators. Troponin I levels frequently fluctuate within and outside the reference range, potentially causing misinterpretations by clinicians. Although a negative troponin I result is valuable for excluding myocarditis, its specificity is low. Moreover, the clinical diagnosis of paediatric myocarditis is exceptionally challenging, and accurate early-stage diagnosis and treatment pose difficulties. Currently, the Dallas criteria, involving cardiac biopsy, serves as the gold standard for myocarditis diagnosis. However, this method has several drawbacks and is unsuitable for children, resulting in its limited use.

METHODS AND ANALYSIS

In this study, we will employ multiple logistic regression analysis to develop a predictive model for early childhood myocarditis. This model will assess the patient's condition at onset and provide the probability of a myocarditis diagnosis. Model performance will be evaluated for accuracy and calibration, and the results will be presented through receiver operating characteristic (ROC) curves and calibration plots. Clinical decision curve analysis, in conjunction with ROC curve analysis, will be employed to determine the optimal cut-off value and calculate the net clinical benefit value for assessing clinical effectiveness. Finally, internal model validation will be conducted using bootstrapping.

ETHICS AND DISSEMINATION

Approval from the Clinical Research Ethics Committee of The Third Affiliated Hospital of Wenzhou Medical University has been obtained. The research findings will be disseminated through presentations at scientific conferences and publication in peer-reviewed journals.

Ultra-early myocardial calcification secondary to fulminant myocarditis with 4 years of follow-up: a case report

BACKGROUND

Early myocardial calcifications secondary to fulminant myocarditis (FM) are rare, and their natural evolution and effects on cardiac function are poorly understood. Here, we followed the patient for 4 years to observe the development of cardiac calcification and its impact on heart function.

CASE SUMMARY

A 16-year-old man was hospitalized with a fever and cough for 1 day. The patient was previously healthy and had no history of heart disease or specific family conditions. The patient was positive for anti-Epstein-Barr virus IgG and IgM. The computed tomography (CT) scan showed no coronary lesions. Cardiogenic shock and recurrent ventricular fibrillation developed on the third day after admission, and the patient received rescue therapy such as endotracheal intubation, defibrillation, extracorporeal membrane oxygenation, and corticosteroids. On the 13th day of admission, a CT scan revealed significant calcification in the left ventricular wall. The patient was discharged after 30 days in the hospital. After discharge, his left ventricular calcification peaked at 6 months and gradually subsided after that, and his left ventricular function slowly returned to normal at 12 months.

DISCUSSION

In younger patients, myocardial calcifications secondary to FM may occur as early as 13 days and affect cardiac function. After proper treatment and rehabilitation, the patient's myocardial calcification can gradually subside and the cardiac function can gradually recover. For FM patients, timely and comprehensive intensive treatment, including heart, lung, and kidney replacement therapy and early administration of hormone preparations, may be beneficial to the early recovery of patients.

Quantitative cardiac MRI parameters for assessment of myocarditis in children and adolescents: a systematic review and meta-analysis

AIM

To evaluate the role of quantitative cardiac magnetic resonance imaging (CMRI) parameters in myocarditis, including acute and chronic myocarditis (AM and CM), for children and adolescents.

MATERIALS AND METHODS

PRISMA principles were followed. PubMed, EMBASE, Web of Science, Cochrane Library, and grey literature were searched. The Newcastle-Ottawa Scale (NOS) and the Agency for Healthcare Research and Quality (AHRQ) checklist were utilised for quality assessment. Quantitative CMRI parameters were extracted and a meta-analysis was performed in comparison with healthy controls. The overall effect size was measured as the weighted mean difference (WMD).

RESULTS

Ten quantitative CMRI parameters of seven studies were analysed. Compared with the control group, the myocarditis group reported longer native T1 relaxation time (WMD=54.00, 95% confidence interval [CI]: 33.21,74.79, p<0.001), longer T2 relaxation time (WMD=2.13, 95% CI: 0.98, 3.28, p<0.001), increased extracellular volume (ECV; WMD=3.13, 95% CI: 1.34,4.91, p=0.001), elevated early gadolinium enhancement (EGE) ratio (WMD=1.47, 95% CI: 0.65,2.28, p<0.001), and increased T2-weighted ratio (WMD=0.43, 95% CI: 0.21,0.64, p<0.001). The AM group had longer native T1 relaxation times (WMD=72.02, 95% CI: 32.78,111.27, p<0.001), increased T2-weighted ratios (WMD=0.52, 95% CI: 0.21,0.84 p=0.001), and impaired left ventricular ejection fractions (LVEF; WMD=-5.84, 95% CI: -9.69, -1.99, p=0.003). Impaired LVEF (WMD=-2.24, 95% CI: -3.32, -1.17, p<0.001) was observed in the CM group.

CONCLUSION

Statistical differences can be observed in some CMRI parameters between patients with myocarditis and healthy controls; however, apart from native T1 mapping, there were no large differences in other parameters between two groups, which may reveal the limited benefit of CMRI in assessing myocarditis in children and adolescents.

A combination of Sophora flavescens alkaloids and Panax quinquefolium saponins attenuates coxsackievirus B3‑induced acute myocarditis in mice via NF‑κB signaling

Timely treatment of viral myocarditis (VMC), a form of cardiac inflammation caused by viral infections, can reduce the occurrence of dilated cardiomyopathy and sudden death. Our previous study demonstrated the anti-inflammatory and anti-fibrotic effects of KX, a combination of Sophora flavescens alkaloids and Panax quinquefolium saponins, on an autoimmune myocarditis model in vivo. The present study explored the effects of KX on coxsackievirus B3 (CVB3)-induced acute VMC in mice. Mice were randomly divided into four groups: Control, VMC, KX-high (275 mg/kg) and KX-low (138 mg/kg). Mice in the VMC, KX-high and KX-low groups received injections of CVB3 to establish the VMC model, and those in the KX-high and KX-low groups also received KX by gavage (10 ml/kg) 2 h after virus injection until euthanasia was performed on day 7 or 21. Mice in the control group received an equal KX volume of purified water. The levels of lactate dehydrogenase (LDH), creatine kinase-myocardial band (CK-MB), cardiac troponin I (cTn-I), IL-1β, IL-6, TNF-α and high-sensitive C-reactive protein (hs-CRP) in mouse serum was measured using ELISA. Myocardial tissue structure and degree of injury were observed using hematoxylin and eosin staining. Western blotting and reverse transcription-quantitative PCR were performed to detect the expression levels of NF-κB pathway-related mRNA and protein in myocardial tissue. The results showed that the inflammation and myocardial damage levels of the mice in the VMC group were higher at 7 days than those at 21 days. At both 7 and 21 days, KX decreased the serum CK-MB, LDH, cTn-I, IL-6, TNF-α and hs-CRP levels, and inhibited NF-κB pathway-related mRNA and protein expression in the myocardium of mice. These findings indicated that KX may reduce the inflammatory response and attenuate the pathological damage in the acute and subacute phases of CVB3-induced VMC through the NF-κB pathway.

Leitlinie Myokarditis der Deutschen Gesellschaft für Pädiatrische Kardiologie

This consensus statement presents updated recommendations on diagnosis and treatment of myocarditis in childhood.

Global, regional, and national burdens of myocarditis, 1990-2019: systematic analysis from GBD 2019 : GBD for myocarditis

OBJECTIVES

Myocarditis, a health-threatening heart disease, is attracting increasing attention. This systematic study was conducted to study the prevalence of disease through the trends of incidence, mortality, disability-adjusted life years (DALYs) over the last 30 years, which would be helpful for the policymakers to better the choices for reasonable decisions.

METHODS

The global, regional, and national burdens of myocarditis from 1990-2019 were analyzed by using the 2019 Global Burden of Disease (GBD) database. This study on myocarditis produced new findings according to age, sex, and Social-Demographic Index (SDI) by investigating DALYs, age-standardized incidence rate (ASIR), age-standardized death rate (ASDR), and corresponding estimated annual percentage change (EAPC).

RESULTS

The number of myocarditis incidence increased by 62.19%, from 780,410 cases in 1990 to 1,265,770 cases in 2019. The ASIR decreased by 4.42% (95%CI, from -0.26% to -0.21%) over the past 30 years. The number of deaths from myocarditis increased by 65.40% from 19,618 in 1990 to 324,490 in 2019, but the ASDR was relatively stable over the investigated period. ASDR increased in low-middle SDI regions (EAPC=0.48; 95%CI, 0.24 to 0.72) and decreased in low SDI regions (EAPC=-0.97; 95%CI, from -1.05 to -0.89). The age-standardized DALY rate decreased by 1.19% (95%CI, from -1.33% to -1.04%) per year.

CONCLUSIONS

Globally, the ASIR and DALY for myocarditis decreased and the ASDR was stable over the past 30 years. The risk of incidences and death cases increased with age. Measures should be taken to control the risk of myocarditis in high-burden regions. Medical supplies should be improved in the high-middle SDI regions and middle SDI regions to reduce the deaths from myocarditis in these regions.

Pediatric Myocarditis

Myocarditis is a condition caused by acute or chronic inflammation of the cardiac myocytes, resulting in associated myocardial edema and myocardial injury or necrosis. The exact incidence is unknown, but is likely underestimated, with more mild cases going unreported. Diagnosis and appropriate management are paramount in pediatric myocarditis, as it remains a recognized cause of sudden cardiac death in children and athletes. Myocarditis in children is most often caused by a viral or infectious etiology. In addition, there are now two highly recognized etiologies related to Coronavirus disease of 2019 (COVID-19) infection and the COVID-19 mRNA vaccine. The clinic presentation of children with myocarditis can range from asymptomatic to critically ill. Related to severe acute respiratory syndrome-Coronavirus 2 (SARs-CoV-2), children are at greater risk of developing myocarditis secondary to COVID-19 compared to the mRNA COVID-19 vaccine. Diagnosis of myocarditis typically includes laboratory testing, electrocardiography (ECG), chest X-ray, and additional non-invasive imaging studies with echocardiogram typically being the first-line imaging modality. While the reference standard for diagnosing myocarditis was previously endomyocardial biopsy, with the new revised Lake Louise Criteria, cardiac magnetic resonance (CMR) has emerged as an integral non-invasive imaging tool to assist in the diagnosis. CMR remains critical, as it allows for assessment of ventricular function and tissue characterization, with newer techniques, such as myocardial strain, to help guide management both acutely and long term.

Development of myocarditis and pericarditis after COVID-19 vaccination in children and adolescents: A systematic review

Myocarditis and pericarditis have been reported after COVID-19 vaccine administration in children and adolescents, raising the concern about their possible association with these vaccines. The objective was to explore the incidence, clinical presentation, and association of myocarditis and pericarditis with COVID-19 vaccines in children and adolescents. We conducted a systematic literature search on three databases, that is, Cochrane, MEDLINE/PubMed, and EMBASE from inception till March 2022. A total of three case reports, four case series, and six observational studies were included in the review. For case reports and case series, the mean age of the patients was 17.4 years, with 96.9% being male. Chest pain (n = 31, 93.9%), fever (n = 18, 54.5%), myalgias (n = 15, 45.4%) and headache (n = 9, 27.2%) were the most common presentations. Out of 33 patients, 32 (96.9%) of patients received Pfizer-BioNTech whereas only one (3.03%) received Moderna (mRNA 1273). Clinical investigations revealed ST elevation (n = 32, 97%), and elevated CRP (n = 9, 27.2%) and cardiac troponin (n = 29, 87.8%). The pooled incidence of myocarditis and pericarditis from observational studies was (0.00063%) and (0.000074%) %, respectively. Myocarditis and pericarditis in children and adolescents after the COVID-19 vaccines were more prevalent among males and more commonly observed after the second dose of Pfizer. Though the overall incidence was low, however, the clinicians should consider myocarditis and pericarditis as probable diagnosis when encountering young patients, with a history of vaccine administration, presenting with suggestive findings.

Designer Functional Nanomedicine for Myocardial Repair by Regulating the Inflammatory Microenvironment

Acute myocardial infarction is a major global health problem, and the repair of damaged myocardium is still a major challenge. Myocardial injury triggers an inflammatory response: immune cells infiltrate into the myocardium while activating myofibroblasts and vascular endothelial cells, promoting tissue repair and scar formation. Fragments released by cardiomyocytes become endogenous “danger signals”, which are recognized by cardiac pattern recognition receptors, activate resident cardiac immune cells, release thrombin factors and inflammatory mediators, and trigger severe inflammatory responses. Inflammatory signaling plays an important role in the dilation and fibrosis remodeling of the infarcted heart, and is a key event driving the pathogenesis of post-infarct heart failure. At present, there is no effective way to reverse the inflammatory microenvironment in injured myocardium, so it is urgent to find new therapeutic and diagnostic strategies. Nanomedicine, the application of nanoparticles for the prevention, treatment, and imaging of disease, has produced a number of promising applications. This review discusses the treatment and challenges of myocardial injury and describes the advantages of functional nanoparticles in regulating the myocardial inflammatory microenvironment and overcoming side effects. In addition, the role of inflammatory signals in regulating the repair and remodeling of infarcted hearts is discussed, and specific therapeutic targets are identified to provide new therapeutic ideas for the treatment of myocardial injury.

Myocarditis in a Pediatric Patient with Campylobacter Enteritis: A Case Report and Literature Review

Myocarditis represents a potential complication of various infectious and noninfectious agents and a common diagnostic challenge for clinicians. Data regarding Campylobacter-associated myocarditis are limited. Here, a case of a 13-year-old female with Campylobacter jejuni gastroenteritis complicated by myocarditis is presented, followed by a literature review in order to retrieve information about Campylobacter-associated carditis in the pediatric population. A search on MEDLINE/PubMed yielded 7relevant cases in the last 20 years. Most of them (six/seven) were males and the mean age was 16.1 years. All patients presented with gastrointestinal symptoms followed in six/seven cases by chest pain within two to seven days. Campylobacter was isolated from stool cultures in six patients; abnormal electrocardiographic findings were detected in six; and abnormal echocardiographic findings in three of the cases. Five patients were treated with antibiotics. Full recovery was the clinical outcome in six patients, whereas one patient died. Concerning the nonspecific symptoms of patients with myocarditis, high clinical suspicion of this complication is necessary in cases where patients with a recent infection present with chest pain and elevated cardiac biomarkers.

The Main Causes and Mechanisms of Increase in Cardiac Troponin Concentrations Other Than Acute Myocardial Infarction (Part 1): Physical Exertion, Inflammatory Heart Disease, Pulmonary Embolism, Renal Failure, Sepsis

The causes and mechanisms of increased cardiac troponin T and I (cTnT and cTnI) concentrations are numerous and are not limited to acute myocardial infarction (AMI) (ischemic necrosis of cardiac myocytes). Any type of reversible or irreversible cardiomyocyte injury can result in elevated serum cTnT and cTnI levels. Researchers and practitioners involved in the diagnosis and treatment of cardiovascular disease, including AMI, should know the key causes and mechanisms of elevated serum cTnT and cTnI levels. This will allow to reduce or completely avoid diagnostic errors and help to choose the most correct tactics for further patient management. The purpose of this article is to discuss the main causes and mechanisms of increase in cardiac troponins concentrations in frequently occurring physiological (physical exertion, psycho-emotional stress) and pathological conditions (inflammatory heart disease, pulmonary embolism, chronic renal failure and sepsis (systemic inflammatory response)) not related to myocardial infarction.

Elevation Mechanisms and Diagnostic Consideration of Cardiac Troponins under Conditions Not Associated with Myocardial Infarction. Part 1

Although cardiac troponins are considered the most specific biomarkers for the diagnosis of acute myocardial infarction (AMI), their diagnostic consideration goes far beyond the detection of this dangerous disease. The mechanisms of cardiac troponin elevation are extremely numerous and not limited to ischemic necrosis of cardiac myocytes. Practitioners should be well aware of the underlying pathological and physiological conditions that can lead to elevated serum levels of cardiac troponins to avoid differential diagnostic errors, which will be greatly increased if clinicians rely on laboratory data alone. This article presents a classification of the main causes of an elevation in cardiac troponins and discusses in detail the mechanisms of such elevation and the diagnostic consideration of cardiac troponins in some conditions not associated with AMI, such as physical exertion, inflammatory heart diseases (myocarditis and endocarditis), pulmonary embolism (PE), renal failure, and systemic inflammation (sepsis).