Myopericarditis in children: elevated troponin I level does not predict outcome

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.

High risk and low prevalence diseases: Myocarditis

INTRODUCTION

Myocarditis is a serious condition that carries with it a high rate of morbidity and mortality.

OBJECTIVE

This review highlights the pearls and pitfalls of myocarditis, including presentation, diagnosis, and management in the emergency department (ED) based on current evidence.

DISCUSSION

Myocarditis is an inflammatory syndrome of myocardium, most often resulting from a viral infection, that can cause life-threatening cardiovascular collapse. It has a highly variable presentation and no widely available specific diagnostic test, making it a challenging diagnosis. Emergency clinicians should obtain an electrocardiogram and perform bedside ultrasound to assess cardiac function. Treatment in the ED is largely supportive, focusing on resuscitation, cardiovascular support, cardiology specialist consultation, and appropriate disposition.

CONCLUSIONS

An understanding of myocarditis can assist emergency clinicians in diagnosing and managing this potentially deadly disease.

Do quantitative levels of cardiac troponin I implicate on severity of disease in children, adolescences, and young adults with acute myocarditis and myopericarditis?

OBJECTIVES

When cardiac muscle damage occurs, cardiac troponins are released to blood and their detection is used as a marker in clinical setting. The prognostic value of the quantitative levels of blood troponin I in cases of myocarditis and myopericarditis is unclear. The aim of this study was to analyse whether troponin quantitative blood levels can be correlated with the course of hospitalisation and prognosis.

METHODS

Retrospective data was collected from all consecutive patients aged ≤30 hospitalised with a diagnosis of acute myocarditis or acute myopericarditis in our health Care Campus between the years 2010-2016.

RESULTS

Ninety-three patients with myocarditis and myopericarditis were identified. Higher peak troponin levels correlated with longer hospitalisation times in the cardiac or paediatric wards (p = 0.03, Pearson correlation: r -0.23), and median troponin level at admission correlated with longer overall hospitalisation (p = 0.026, Pearson correlation: r = 0.23). Patients admitted to ICU, received oral cardiac supportive therapy or that were discharged with cardiac drugs had higher median troponin compared to patients who were not but this was not statistically significant. A small group of patients that needed intravenous cardiac support had significantly lower median peak troponin levels (n = 4, 0.375ng/ml, p = 0.048). Only two patients needed extracorporeal membrane oxygenation support, and one died. The small number of patients precludes statistical analysis.

CONCLUSION

Higher troponin levels correlated significantly with longer hospitalisation, lower troponin values correlated with intravenous cardiac support, while other variables related to the severity of disease could not be significantly related to higher troponin levels.

Comparison of Multisystem Inflammatory Syndrome in Children-Related Myocarditis, Classic Viral Myocarditis, and COVID-19 Vaccine-Related Myocarditis in Children

Background Although rare, classic viral myocarditis in the pediatric population is a disease that carries significant morbidity and mortality. Since 2020, myocarditis has been a common component of multisystem inflammatory syndrome in children (MIS-C) following SARS-CoV-2 infection. In 2021, myocarditis related to mRNA COVID-19 vaccines was recognized as a rare adverse event. This study aims to compare classic, MIS-C, and COVID-19 vaccine-related myocarditis with regard to clinical presentation, course, and outcomes. Methods and Results In this retrospective cohort study, we compared patients aged <21 years hospitalized at our institution with classic viral myocarditis from 2015 to 2019, MIS-C myocarditis from March 2020 to February 2021, and vaccine-related myocarditis from May 2021 to June 2021. Of 201 total participants, 43 patients had classic myocarditis, 149 had MIS-C myocarditis, and 9 had vaccine-related myocarditis. At presentation, ejection fraction was lowest for those with classic myocarditis, with ejection fraction <55% present in 58% of patients. Nearly all patients with MIS-C myocarditis (n=139, 93%) and all patients with vaccine-related myocarditis (n=9, 100%) had normal left ventricular ejection fraction at the time of discharge compared with 70% (n=30) of the classic myocarditis group (P<0.001). At 3 months after discharge, of the 21 children discharged with depressed ejection fraction, none of the 10 children with MIS-C myocarditis had residual dysfunction compared with 3 of the 11 (27%) patients in the classic myocarditis group. Conclusions Compared with classic myocarditis, those with MIS-C myocarditis had better clinical outcomes, including rapid recovery of cardiac function. Patients with vaccine-related myocarditis had prompt resolution of symptoms and improvement of cardiac function.

COVID-19 Vaccine Cardiac Complications: A Case Series on Implications of Marijuana in Adolescents With Myopericarditis

We report on two critically ill pediatric patients, aged 16 and 18 years, presenting with acute myopericarditis at a tertiary-care center in New Jersey, United States. Both patients had their severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccinations, tested negative for SARS-CoV-2, and shared only significant history of asthma. Clinical presentations were similar to acute onset chest pain that worsened with deep inspiration. One patient reported a history of vaping and escalating marijuana use several hours preceding presentation. Both patients had elevated troponin on admission and had ST-segment elevation on electrocardiogram (EKG), thus prompting admission to the pediatric intensive care unit (PICU) for cardiac monitoring. Myopericarditis has multiple etiologies and is a newly described rare complication of the SARS-CoV-2 vaccine. It can also occur as a complication of vaping and frequent marijuana drug use. Our paper highlights the importance of a detailed social and drug history in adolescents presenting with chest pain. The clinical characterization is necessary to promote better case definitions and the design of targeted interventions for this vulnerable group.  

The Prognostic Value of Natriuretic Peptides in Stable Patients with Suspected Acute Myocarditis: A Retrospective Study

Risk stratification in acute myocarditis is based on the clinical signs of heart failure, the degree of cardiac dysfunction, and the findings in cardiac magnetic resonance (CMR). The aim of the current study is to examine the prognostic yield of the natriuretic peptide N-terminal-pro hormone Brain Natriuretic Peptide (NT-proBNP) and C-reactive protein (CRP) in acute myocarditis among patients with preserved/mildly reduced left ventricular ejection fraction (LVEF). We retrospectively analyzed 59 patients (median age 28 years, 76% males) with ICD-9 discharge diagnosis of acute myocarditis. Basic characteristics, echocardiographic, and laboratory parameters were obtained from computerized files. The median length of stay was 3, (IQR 2−5) days, and the median LVEF was 48% (IQR, 54−62%). High levels of NT-proBNP and CRP were associated with increased length of stay (r = 0.57, p < 0.001; r = 0.4 p = 0.001, respectively), while troponin level was not (r = 0.068, p = 0.61). During the index hospitalization, complications occurred in 14 (23.7%) patients. High NT-proBNP and CRP levels were associated with complications (p < 0.001, and p = 0.001, respectively), while troponin level was not (p = 0.452). In conclusion, routine measurement of NT-proBNP and CRP are preferred over troponin for risk stratification in hemodynamically stable myocarditis.

COVID Vaccine-Associated Myocarditis in Adolescent Siblings: Does It Run in the Family?

The development of myocarditis after receiving messenger RNA vaccination against COVID-19 is well documented, particularly in adolescent and young adult males. We report a case of vaccine-associated myocarditis in adolescent brothers following their second dose of the BNT162b2 mRNA vaccine (Pfizer-BioNTech, Mainz, Germany). This report illustrates the need to better understand the mechanisms leading to myocarditis after mRNA vaccination.

The Diagnostic Role of Echocardiographic Strain Analysis in Patients Presenting with Chest Pain and Elevated Troponin: A Multicenter Study

BACKGROUND

Myocarditis presenting as acute chest pain with elevated troponins without significant cardiac compromise is rare in previously healthy children, often referred to as myopericarditis. Diagnosis is challenging as conventional echocardiographic measures of systolic function can be normal. This study aimed to demonstrate the diagnostic utility of strain imaging in this scenario.

METHODS

This is a multi-center retrospective study including patients presenting with chest pain and elevated troponin from 10 institutions who underwent cardiac MRI (CMR) and transthoracic echocardiogram (echo) within 30 days of each other (group 1). Findings were compared to 19 controls (group 2). Clinical data, conventional echo and CMR data were collected. Echo-derived strain was measured at the core lab. Group 1 was divided into subgroups as CMR myocarditis positive (group 1a) or negative (group 1b) based on established criteria.

RESULTS

Group 1 included 108 subjects (88 in group 1a, 20 in group 1b). While all groups had normal mean fractional shortening (FS) and mean left ventricular ejection fraction (LVEF), group 1 had significantly lower EF (56.8+/-7.0) compared to group 2 ( 62.3+/- 4.9, P<0.005) and FS (31.2+/- 4.9) compared to group 2 (34.1+/-3.5, p<0.05). Additionally, peak global longitudinal strain (GLS%) was markedly abnormal in group 1 (-13.9+/-3.4 ) compared to group 2 (-19.8+/-2.1 , P<0.001). In subgroup analysis, GLS% was markedly abnormal in group 1a (-13.2 ± 3.0%) compared to group 1b (-17.3 ± 2.6% and p<0.001). Fifty-four subjects had follow up echocardiograms (46 in group 1a, 8 in group 1b) with mean follow-up time of 10 months (SD=11 months). At follow up, while EF and FS returned to normal in all patients, abnormalities in strain persisted in group 1, with 22% of them still having abnormal GLS. Moreover, mean GLS was more abnormal in group 1a (-16.1 +/- 2.6) compared to group 1b (-17.4+/- 1.2, p<0.05).

CONCLUSIONS

Our study demonstrates that echo GLS% is significantly worse in subjects with myopericarditis presenting with chest pain and elevated troponins compared to controls even when conventional measures of systolic function are largely normal and that these abnormalities persisted overtime.

Myopericarditis in children and adolescent: is the elevated troponin and chest pain as alarming as we thought?

AIM

When encountering adolescents with chest pain and a high troponin level but with no underlying coronary artery illness, it is advisable to consider myopericarditis. Though myopericarditis is a self-limiting, benign condition, it nevertheless causes anxiety in the patient and the family.

METHODS

Thirty-nine patients diagnosed with myopericarditis were included. We retrospectively analysed the demographic and clinical features, laboratory tests, echocardiography, electrocardiograms, MRI findings, coronary CT angiography, and conventional angiography findings in these patients.

RESULTS

Of the 39 patients (female/male = 4/35) aged 7-17 years, 66.6% had viral infection in the 2 weeks preceding presentation. Eleven patients were tested for high-sensitivity cardiac troponin I, 28 for high-sensitivity cardiac troponin T, and 10 patients were tested for both biomarkers. The median hs-TnI and hs-TnT values were 6.3 (0.05-29.9) ng/mL and 586 (51-9398) ng/L, respectively. Twenty-three patients showed ST changes on electrocardiography, of whom 11 had ST-elevation in the leads supporting left ventricular involvement. Coronary CT angiography and catheter angiography evaluations performed for differential diagnosis of coronary anomaly and acute coronary syndrome were normal. Cardiac MRI was conducted on 28 patients, and the results in 10 (35.7%) were suggestive of myopericarditis.

CONCLUSIONS

Myopericarditis is common in the adolescent age group and is generally benign but should be carefully monitored for differential diagnosis and possible complications. Cardiac MRI, which has been used more frequently in recent years, has an important role in differential diagnosis and the follow-up of patients.

Pediatric Myopericarditis Presenting to the Emergency Department as Chest Pain: A Comparative Study With Myocarditis

METHODS

A database query was performed and identified patients over a 9-year period, and clinical data, laboratory data, and cardiac studies were extracted and analyzed from the electronic health record.

RESULTS

A total of 36 patients were identified with the discharge diagnosis of myopericarditis and 22 with myocarditis. The median age for myopericarditis patients was 16.2 years, and 97% were male. The median initial troponin was 7.1 ng/mL, the peak was at 16.6 ng/mL, and 58% had ST changes on electrocardiogram. The median length of stay for myopericarditis patients was 1.7 days, and 50% were discharged home on nonsteroidal anti-inflammatory medication. Compared with myocarditis, myopericarditis patients were older, had a higher incidence of chest pain, and were less likely to have fever, vomiting, abdominal pain, upper respiratory infection symptoms, chest radiograph abnormalities, or T-wave inversion (P < 0.05). Myopericarditis patients also had lower Pediatric Risk of Mortality version 3 scores, B-type natriuretic peptide levels, and higher left ventricular ejection fractions on admission (67% vs 41%; P < 0.05). A classification model incorporating initial left ventricular ejection fraction, B-type natriuretic peptide, electrocardiogram, and chest radiograph findings distinguished myopericarditis from myocarditis with correct classification in 95% of patients.

CONCLUSIONS

Myopericarditis is a relatively common cause of chest pain for patients admitted to the pediatric intensive care unit, presents differently than true myocarditis, and carries a good prognosis.

The absolute and relative changes in high-sensitivity cardiac troponin I are associated with the in-hospital mortality of patients with fulminant myocarditis

Background

We sought to describe the tendency and extent of high-sensitivity cardiac troponin I (hs-cTnI) changes in patients with fulminant myocarditis (FM) after admission and to explore the relationship between the in-hospital mortality of FM and the absolute and relative changes in hs-cTnI within 24 h and 48 h after admission.

Methods

In the retrospective study, the object are patients diagnosed with FM in our single centre. The value of cardiac troponin was recorded after patients admitted to hospital in succession. The absolute and relative changes in hs-cTnI within 24 h and 48 h were described as range distributions. Receiver operating characteristic (ROC) curve and Cox analyses were performed to determine the relationship between in-hospital mortality of FM and hs-cTnI changes.

Results

A total of 83 FM patients admitted to our centre from January 1, 2010 to December 31, 2019 were included; 69 patients survived and 14 patients died. In the survival group, 78% of patients experienced a decline in hs-cTnI within 24 h, while 36% of the mortality group exhibited a declining tendency in hs-cTnI (P = 0.003). Nearly 60% of survival group had a 0–2000 ng/l reduction in troponin from baseline within 24 h of admission. However, troponin levels of 50% of patients in the mortality group were 0–10,000 ng/ L higher than baseline 24 h after admission. Multivariable logistic analysis revealed that the declining tendency of hs-cTnI within 24 h, in addition to time from onset to admittance to hospital, intravenous immunoglobulin treatment and the abnormal level of creatinine, were associated with the in-hospital mortality of FM (for the declining tendency of hs-cTnI within 24 h, OR = 0.10, 95% CI 0.02–0.68, P = 0.018). The ROC curve revealed optimal cut-off values of − 618 ng/l for absolute change within 24 h (AUC = 0.800, P < 0.01), − 4389 ng/l for absolute change within 48 h (area under the curve = 0.711, P < 0.01), − 28.46% for relative change within 24 h (AUC = 0.810, P < 0.01), and − 52.23% for relative change within 48 h (AUC = 0.795, P < 0.01). Absolute changes and relative changes in hs-cTnI within 24 h and 48 h were strong predictors of in-hospital mortality by Cox regression analysis after adjustment for sex, time from onset to admission, and occurrence of ventricular tachycardia or ventricular fibrillation.

Conclusion

Most FM patients who survived experienced a decline in hs-cTnI within 24 h. The absolute and relative changes in hs-cTnI within 24 h and 48 h were strong predictors of in-hospital mortality.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12872-021-02386-8.

Cardiac MRI and Myocardial Injury in COVID-19: Diagnosis, Risk Stratification and Prognosis

Myocardial injury is a common complication of the COVID-19 illness and is associated with a worsened prognosis. Systemic hyperinflammation seen in the advanced stage of COVID-19 likely contributes to myocardial injury. Cardiac magnetic resonance imaging (CMR) is the preferred imaging modality for non-invasive evaluation in acute myocarditis, enabling risk stratification and prognostication. Modified scanning protocols in the pandemic setting reduce risk of exposure while providing critical data regarding cardiac tissue inflammation and fibrosis, chamber remodeling, and contractile function. The growing use of CMR in clinical practice to assess myocardial injury will improve understanding of the acute and chronic sequelae of myocardial inflammation from various pathological etiologies.

Evaluating Chest Pain and Heart Murmurs in Pediatric and Adolescent Patients

Chest pain and heart murmurs are common issues primary care providers must evaluate and manage. Both are a source of anxiety for patients, parents, and providers, necessitating evaluation and understanding to ensure appropriate management. Most pediatric chest pain can be treated symptomatically and with reassurance. This article examines the approach to pediatric chest pain including identification of key historical points, common causes of chest pain, and when to refer. The article also delineates our approach to auscultation, describes common benign murmurs, and offers suggestions on when to refer for further evaluation.

Management of Myocarditis in Myositis: Diagnosis and Treatment

PURPOSE OF REVIEW

To provide a summary of the current knowledge on myocarditis in idiopathic inflammatory myopathies (IIMs).

RECENT FINDINGS

There is increasing epidemiological knowledge about heart involvement generally and myocarditis specifically in IIMs. Cardiac magnetic resonance (CMR) plays an important role in this regard. Myocarditis occupies an important place in the spectrum of pathologies that involve the myocardium in patients with IIMs. Nevertheless, its full impact still remains to be elucidated. A larger cooperation between rheumatologists and cardiologists in the clinical, as well as in the research field, is necessary to expand our knowledge in the area.

Myocardial Injury in the Era of High-Sensitivity Cardiac Troponin Assays: A Practical Approach for Clinicians

Importance

Traditionally, elevated troponin concentrations were synonymous with myocardial infarction. But with improvements in troponin assays, elevated concentrations without overt myocardial ischemia are now more common; this is referred to as myocardial injury. Physicians may be falsely reassured by the absence of myocardial ischemia; however, recent evidence suggests that myocardial injury is associated with even more detrimental outcomes. Accordingly, this article reviews the definition, epidemiology, differential diagnosis, diagnostic evaluation, and management of myocardial injury.

Observations

Current epidemiological evidence suggests that myocardial injury without overt ischemia represents about 60% of cases of abnormal troponin concentrations when obtained for clinical indications, and 1 in 8 patients presenting to the hospital will have evidence of myocardial injury. Myocardial injury is a concerning prognosis; the 5-year mortality rate is approximately 70%, with a major adverse cardiovascular event rate of 30% in the same period. The differential diagnosis is broad and can be divided into acute and chronic precipitants. The initial workup involves an assessment for myocardial ischemia. If infarction is ruled out, further evaluation includes a detailed history, physical examination, laboratory testing, a 12-lead electrocardiogram, and (if there is no known history of structural or valvular heart disease) an echocardiogram. Unfortunately, no consensus exists on routine management of patients with myocardial injury. Identifying and treating the underlying precipitant is the most practical approach.

Conclusion and Relevance

Myocardial injury is the most common cause of abnormal troponin results, and its incidence will likely increase with an aging population, increasing prevalence of cardiovascular comorbidities, and greater sensitivity of troponin assays. Myocardial injury represents a challenge to clinicians; however, given its serious prognosis, it warrants a thorough evaluation of its underlying precipitant. Future strategies to prevent and/or manage myocardial injury are needed.

Myoglobin for Detection of High-Risk Patients with Acute Myocarditis

There is an unmet need for accurate and practical screening to detect myocarditis. We sought to test the hypothesis that the extent of acute myocarditis, measured by late gadolinium enhancement (LGE) on cardiac magnetic resonance imaging (CMR), can be estimated based on routine blood markers. A total of 44 patients were diagnosed with acute myocarditis and included in this study. There was strong correlation between myoglobin and LGE (r_s = 0.73 [95% CI 0.51; 0.87], p < 0.001), while correlation was weak between LGE and TnT-hs (r_s = 0.37 [95% CI 0.09; 0.61], p = 0.01). Receiver operating curve (ROC) analysis determined myoglobin ≥ 87 μg/L as cutoff to identify myocarditis (92% sensitivity, 80% specificity). The data were reproduced in an established model of coxsackievirus B3 myocarditis in mice (n = 26). These data suggest that myoglobin is an accurate marker of acute myocarditis. Graphical Abstract Receiver operating curve analysis determined myoglobin ≥ 87 μg/L as cutoff to identify myocarditis and these data were reproduced in an established model of coxsackievirus B3 myocarditis in mice: CMRI, cardiac magnetic resonance imaging; Mb, myoglobin; LGE, late gadolinium enhancement; ROC, receiver operating curve analysis.

Outcomes of Myocarditis in Patients with Normal Left Ventricular Systolic Function on Admission

The objective of this study was to describe a cohort of patients with clinical myocarditis and normal left ventricular (LV) systolic function on admission. A retrospective chart review at seven tertiary pediatric hospitals identified patients aged < 19 years admitted with an ICD-9 code of myocarditis between 2008 and 2012. Patients were excluded if admission LV systolic ejection fraction was < 50%, fractional shortening (FS) was < 28% or if the admitting or consulting cardiologist did not suspect myocarditis. A total of 75 patients met inclusion criteria. The median age was 15.5 years with an Interquartile Range (IQR) of 13.6-16.6. 33% were female. Patients presented most commonly with chest pain (75%) and dyspnea (24%). On admission, median B-type natriuretic peptide (BNP) was 132 pg/mL (IQR 57-689) and median troponin I (TnI) was 8.4 ng/mL (IQR 2.0-20.3). Electrocardiogram revealed ST elevation in the majority (55%). Magnetic resonance imaging was obtained on 40%, with 63% of those showing evidence of inflammation. Therapies included inotropic support (15%), mechanical ventilation (12%), antiarrhythmic medications (9%), and Extracorporeal Membrane Oxygenation (5%). Those with poor outcomes were noted to have significantly higher BNP, TnI, and creatine kinase levels on presentation. One patient was transplanted and 35% were discharged on heart failure medications. At one year follow-up one patient had died of unspecified causes, 15% required readmission for cardiac reasons, and 21% continued on heart failure medications. The risk associated with clinical myocarditis in the setting of normal ventricular function at presentation may be higher than previously suspected.

Analysis of clinical parameters and echocardiography as predictors of fatal pediatric myocarditis

Pediatric myocarditis symptoms can be mild or as extreme as sudden cardiac arrest. Early identification of the severity of illness and timely provision of critical care is helpful; however, the risk factors associated with mortality remain unclear and controversial. We undertook a retrospective review of the medical records of pediatric patients with myocarditis in a tertiary care referral hospital for over 12 years to identify the predictive factors of mortality. Demographics, presentation, laboratory test results, echocardiography findings, and treatment outcomes were obtained. Regression analyses revealed the clinical parameters for predicting mortality. During the 12-year period, 94 patients with myocarditis were included. Of these, 16 (17%) patients died, with 12 succumbing in the first 72 hours after admission. Fatal cases more commonly presented with arrhythmia, hypotension, acidosis, gastrointestinal symptoms, decreased left ventricular ejection fraction, and elevated isoenzyme of creatine kinase and troponin I levels than nonfatal cases. In multivariate analysis, troponin I > 45 ng/mL and left ventricular ejection fraction < 42% were significantly associated with mortality. Pediatric myocarditis had a high mortality rate, much of which was concentrated in the first 72 hours after hospitalization. Children with very high troponin levels or reduced ejection fraction in the first 24 hours were at higher risk of mortality, and targeting these individuals for more intensive therapies may be warranted.

In-hospital and post-discharge outcomes of pediatric acute myocarditis underwent after high-dose steroid or intravenous immunoglobulin therapy

Background

High-dose steroids and intravenous immunoglobulin (IVIG) are controversial treatments for pediatric patients with acute myocarditis. This study aimed to investigate their efficacies in the Taiwanese pediatric population.

Methods

This study evaluated 5563 acute myocarditis patients from the Taiwan’s National Health Insurance Research Database and identified 1542 pediatric patients hospitalized for acute myocarditis between January 1, 2001 and December 31, 2011. The exclusion criteria were age of > 11 years, associated cardiovascular comorbidities, autoimmune disease, malignancy before the index hospitalization, extracorporeal membrane oxygenation, intra-aortic balloon pumping, and dual therapy using IVIG and high-dose steroids.

Results

After 2:1 propensity score matching, we identified 208 subjects without steroid therapy and 104 subjects who received high-dose steroids. The mean age in that cohort was 2.6 ± 2.9 years, and high-dose steroid therapy had no significant effects on major in-hospital complications and post-discharge outcomes. After 2:1 propensity score matching, we identified 178 subjects without IVIG therapy and 89 subjects who received IVIG. The mean age in that cohort was 2.0 ± 2.1 years, and IVIG had no significant effects on the major outcomes.

Conclusions

The present study revealed that high-dose steroid or IVIG therapy had no significant effects on major in-hospital complications, late heart failure hospitalization, and long-term mortality.

Artificial cardiac pacemaker placement in dogs with a cohort of myocarditis suspects and association of ultrasensitive cardiac troponin I with survival

INTRODUCTION

Artificial cardiac pacemakers (APs) are a common treatment for symptomatic bradyarrhythmias in dogs, some of which may be triggered by underlying myocarditis. Severely elevated cardiac troponin I (cTnI) concentrations support a diagnosis of myocarditis. The association of ultrasensitive-cTnI (US-cTnI) concentration with survival in a large cohort of dogs receiving APs is not described.

ANIMALS, MATERIALS, AND METHODS

The study included 110 dogs receiving APs over a 5-year period. Medical records were retrospectively reviewed to characterize the entire population receiving APs, with further analysis in dogs with preprocedural US-cTnI concentrations (n = 64) classified as normal/group 1 (n = 11), mildly to moderately elevated/group 2 (n = 27), and severely elevated/myocarditis suspects/group 3 (n = 26).

RESULTS

Median survival time was 1079 days for the entire population, 1167 days for group 2, 949 days for group 3, and not met in group 1. There was not a statistically significant difference in survival between group 2 and group 3. Overall, US-cTnI had a mild, negative association with survival. Age had a stronger negative association. Infectious etiologies were identified in a minority of group 3 cases. A possible association between severely elevated US-cTnI and a sudden death outcome was noted.

CONCLUSIONS

The negative association of US-cTnI with survival outcomes was mild, with age having a larger effect. Although a sudden death outcome may be seen more commonly in myocarditis suspects, group 3 survival time was similar to that of the entire canine population. Plausible infectious causes of myocarditis were infrequently identified.

Elevated Troponin in the First 72 h of Hospitalization for Pediatric Viral Myocarditis is Associated with ECMO: An Analysis of the PHIS+ Database

Serum troponin (Tn) is often elevated in viral myocarditis; however, its prognostic significance is unknown. We tested the hypothesis that abnormal serum Tn is associated with mortality in children hospitalized with myocarditis. We retrospectively studied data from six large children's hospitals participating in the Pediatric Health Information System Plus (PHIS+) database. Analysis was performed on patients hospitalized with viral myocarditis between 2007 and 2013, in whom at least one Tn was recorded within 72 h of admission. Abnormal baseline Tn was defined as any value outside the upper limit of normal within the first 72 h. Primary outcome was mortality. Secondary outcomes included mechanical support, defined as use of extracorporeal membrane oxygenation (ECMO) or a ventricular assist device (VAD), cardiac transplantation, intravenous immunoglobulin (IVIg), mechanical ventilation, and inotrope use. A total of 149 patients with myocarditis (61% male, 48% adolescents) across all PHIS+ centers had TnI (n = 113) or TnT (n = 36) recorded. At least one abnormal Tn was present in 81% of cases. Overall mortality was 7.3% and was not associated with abnormal baseline Tn. Abnormal baseline Tn was associated with ECMO (7.1 vs. 25.6%, p = 0.03) and IVIg (46.4 vs. 83.5%, p < 0.001). Abnormal baseline Tn was not associated with transplantation, mechanical ventilation or inotrope use. Abnormal Tn in the first 72 h of hospitalization for myocarditis was associated with the use of ECMO and IVIg, but was not associated with mortality. This finding may help risk stratify this population if it can be prospectively validated.

Diagnostic role of strain imaging in atypical myocarditis by echocardiography and cardiac MRI

BACKGROUND

The diagnosis of myocarditis presenting as isolated acute chest pain with elevated troponins but normal systolic function is challenging with significant drawbacks even for the gold-standard endomyocardial biopsy.

OBJECTIVE

This study aimed to evaluate the diagnostic role of strain imaging by echocardiography and cardiac MRI in these patients.

MATERIALS AND METHODS

This was a retrospective review of children with cardiac MRI for acute chest pain with elevated troponins compared to normal controls. Echocardiographic fractional shortening, ejection fraction, speckle-tracking-derived peak longitudinal, radial, and circumferential strain were compared to cardiac MRI ejection fraction, T2 imaging, late gadolinium enhancement, speckle-tracking-derived peak longitudinal strain, radial strain, and circumferential strain.

RESULTS

Group 1 included 10 subjects diagnosed with myocarditis, 9 (90%) males with a median age of 15.5 years (range: 14-17 years) compared with 10 age-matched controls in group 2. All subjects in group 1 had late gadolinium enhancement consistent with myocarditis and troponin ranged from 2.5 to >30 ng/ml. Electrocardiogram changes included ST segment elevation in 6 and abnormal Q waves in 1. Qualitative echocardiographic function was normal in both groups and mean fractional shortening was similar (35±6% in group 1 vs. 34±4% in group 2, P=0.70). Left ventricle ejection fraction by cardiac MRI, however, was lower in group 1 (52±9%) compared to group 2 at (59±4%) (P=0.03). Cardiac MRI derived strain was lower in group 1 vs. group 2 for speckle-tracking-derived peak longitudinal strain (-12.8±2.8% vs. -17.1±1.5%, P=0.001), circumferential strain (-12.3±3.8% vs. -15.8±1.2%, P=0.020) and radial strain (13.6±3.7% vs. 17.2±3.2%, P=0.040). Echocardiography derived strain was also lower in group 1 vs. group 2 for speckle-tracking-derived peak longitudinal strain (-15.6±3.9% vs. -20.8±2.2%, P<0.002), circumferential strain (-16±3% vs. -19.8±1.9%, P<0.003) and radial strain (17.3±6.1% vs. 24.8±6.3%, P=0.010).

CONCLUSION

In previously asymptomatic children, myocarditis can present with symptoms of acute chest pain suspicious for coronary ischemia. Cardiac MRI and echocardiographic strain imaging are noninvasive, radiation-free tests of immense diagnostic utility in these situations. Long-term studies are needed to assess prognostic significance of these findings.

Cardiac Magnetic Resonance Imaging in Myocarditis Reveals Persistent Disease Activity Despite Normalization of Cardiac Enzymes and Inflammatory Parameters at 3-Month Follow-Up

BACKGROUND

There is a major unmet need to identify high-risk patients in myocarditis. Although decreasing cardiac and inflammatory markers are commonly interpreted as resolving myocarditis, this assumption has not been confirmed as of today. We sought to evaluate whether routine laboratory parameters at diagnosis predict dynamic of late gadolinium enhancement (LGE) as persistent LGE has been shown to be a risk marker in myocarditis.

METHODS AND RESULTS

Myocarditis was diagnosed based on clinical presentation, high-sensitivity troponin T, and cardiac magnetic resonance imaging, after exclusion of obstructive coronary artery disease by angiography. Cardiac magnetic resonance imaging was repeated at 3 months. LGE extent was analyzed with the software GT Volume. Change in LGE >20% was considered significant. Investigated cardiac and inflammatory markers included high-sensitivity troponin T, creatine kinase, myoglobin, N-terminal B-type natriuretic peptide, C-reactive protein, and leukocyte count. Twenty-four patients were enrolled. Absolute levels of cardiac enzymes and inflammatory markers at baseline did not predict change in LGE at 3 months. Cardiac and inflammatory markers had normalized in 21 patients (88%). LGE significantly improved in 16 patients (67%); however, it persisted to a lesser degree in 17 of them (71%) and increased in a small percentage (21%) despite normalization of cardiac enzymes.

CONCLUSIONS

This is the first study reporting that cardiac enzymes and inflammatory parameters do not sufficiently reflect LGE in myocarditis. Although a majority of patients with normalizing laboratory markers experienced improved LGE, in a small percentage LGE worsened. These data suggest that cardiac magnetic resonance imaging might add value to currently existing diagnostic tools for risk assessment in myocarditis.

A 17-Year-Old With Chest Pain

A 17-year-old male subject with a history of deep venous thrombosis presented with acute unilateral severe chest pain. His examination was nonspecific, and vital signs were normal. His initial laboratory evaluation revealed mild thrombocytopenia, elevated troponin levels, and critically elevated activated partial thromboplastin time. A computed tomography angiogram of the chest revealed a pulmonary embolus, and anticoagulation therapy was initiated. His course was complicated by the development of multiple thrombi and respiratory failure. Extensive evaluation revealed a rare, underlying diagnosis in time for life-saving treatment to be initiated.

Prognosis of myopericarditis as determined from previously published reports

BACKGROUND

The prognosis of pericarditis with concomitant myocarditis, especially in the setting of troponin elevation, is a reason for concern because it could imply an adverse outcome.

METHODS

We performed a comprehensive Medline search of all publications from 2000 to 2013 with the MeSH terms 'pericarditis', 'myocarditis' and 'prognosis'. Additional publications were sought using the reference lists of identified papers, the published reviews on this topic, and a search of abstracts from the American Heart Association, American College of Cardiology, and European Society of Cardiology scientific sessions.

RESULTS

We identified eight major clinical series evaluating the prognosis of myopericarditis. Studies included a total of 389 patients with myopericarditis (mean age 31.7 years, men-to-women ratio 4.0). After a mean follow-up of 31 months, residual left-ventricular dysfunction was reported in 3.5% without cases of heart failure. Recurrences occurred in 13.0% of cases mainly as recurrent pericarditis (>90%), cardiac tamponade and constrictive pericarditis in less than 1% of cases. The overall prognosis seems good (no mortality), with only one single discordant study reporting three deaths: one related to cardiac tamponade and two sudden cardiac deaths during hospitalization, but no out-of-hospital deaths during follow-up.

CONCLUSION

Myopericarditis has a good overall prognosis. Troponin elevation in this setting does not predict an adverse outcome in most cases. Thus it is important to reassure the patients on their prognosis, explaining the nature of the disease and the likely course. Diagnostic and therapeutic choices should take into account the overall good outcome of these patients, including less invasive diagnostic tools and toxic drugs.

Acute myopericarditis in an adolescent mimicking acute myocardial infarction

Acute myopericarditis is primarily a pericarditic syndrome with variable myocardial involvement, as evidenced by elevated cardiac enzymes. It is a rare entity, exclusively seen in male adolescents and accounts for less than 2% of the cases of inpatient admissions for chest pain/pericarditis in the pediatric age group. The electrocardiographic changes of pericarditis include J point/ST segment elevation, which needs to be differentiated from the benign early repolarization pattern that is common in young adolescents and the subtle anterior ST segment elevation myocardial infarction. Differentiating acute myopericarditis from acute coronary syndromes can be challenging because they share the presenting triad of acute chest pain, ST segment changes, and elevated cardiac enzymes. The accurate distinction of myopericarditis from acute myocarditis or acute coronary syndrome is important because of their differences in risk for specific complications, prognosis, and treatment implications. We present a case of acute myopericarditis in an adolescent who presented with atypical precordial chest pain, accompanied by inferolateral focal electrocardiographic changes and significant elevation of cardiac enzymes. The differential diagnosis and management of myopericarditis is reviewed with a focus on electrocardiographic changes and troponin assays.

Acute myopericarditis associated with cat scratch disease in an adolescent

Cat scratch disease is generally characterized by a self-limited chronic regional lymphadenopathy, but numerous other clinical manifestations involving a variety of organ systems have been reported. Cardiac involvement is unusual and when reported, it has been associated with culture-negative endocarditis in adults. We present the case of an adolescent male with typical cat scratch disease and associated myopericarditis.

Elevated troponin levels in previously healthy children: value of diagnostic modalities and the importance of a drug screen

BACKGROUND

Myocardial injury in previously healthy children is rare, with a wide range of aetiologies. It is increasingly being identified on the basis of elevated troponin levels during routine evaluation of cardiorespiratory symptoms. Establishing the aetiology remains challenging because of the lack of an accepted work-up algorithm. Our objective was to delineate the contribution of diagnostic modalities and troponin patterns towards the final diagnosis.

METHODS

A retrospective chart review of previously healthy patients admitted to the Pediatric Cardiology Service with myocardial injury was carried out. Data analysed included echocardiograms, electrocardiograms, cardiac catheterisations, magnetic resonance imaging, drug screen tests, troponin values, and final diagnosis.

RESULTS

A total of 32 patients were identified. The diagnoses were: myocarditis in 16 patients, vasospasm due to drug use in seven, myopericarditis in six, anomalous coronary artery origins in two, and Prinzmetal's angina in one patient. The electrocardiograms were abnormal in 27 of the 32 patients (84%), echocardiograms in 18 of the 32 patients (56%), cardiac magnetic resonance imaging in two of the four patients (50%), urine drug screen in five of the 25 patients (20%), and cardiac catheterisations in two of the 15 patients (13%).

CONCLUSIONS

Myocarditis is the most common aetiology of myocardial injury in children. Clinical history remains the basic screening tool; drug screens help identify coronary vasospasms secondary to drug use (22% of our cohort). Patients with anomalous coronaries had exertional symptoms. Initial troponin levels and progression were not diagnostic or prognostic. Catheterisation is of limited value and did not change management. Magnetic resonance imaging with gadolinium enhancement is probably the most useful test when initial evaluation is not diagnostic.

Good prognosis for pericarditis with and without myocardial involvement: results from a multicenter, prospective cohort study

BACKGROUND

The natural history of myopericarditis/perimyocarditis is poorly known, and recently published studies have presented contrasting data on their outcomes. The aim of the present article is to assess the prognosis of myopericarditis/perimyocarditis in a multicenter, prospective cohort study.

METHODS AND RESULTS

A total of 486 patients (median age, 39 years; range, 18-83 years; 300 men) with acute pericarditis or a myopericardial inflammatory syndrome (myopericarditis/perimyocarditis; 85% idiopathic, 11% connective tissue disease or inflammatory bowel disease, 5% infective) were prospectively evaluated from January 2007 to December 2011. The diagnosis of acute pericarditis was based on the presence of 2 of 4 clinical criteria (chest pain, pericardial rubs, widespread ST-segment elevation or PR depression, and new or worsening pericardial effusion). Myopericardial inflammatory involvement was suspected with atypical ECG changes for pericarditis, arrhythmias, and cardiac troponin elevation or new or worsening ventricular dysfunction on echocardiography and confirmed by cardiac magnetic resonance. After a median follow-up of 36 months, normalization of left ventricular function was achieved in >90% of patients with myopericarditis/perimyocarditis. No deaths were recorded, as well as evolution to heart failure or symptomatic left ventricular dysfunction. Recurrences (mainly as recurrent pericarditis) were the most common complication during follow-up and were recorded more frequently in patients with acute pericarditis (32%) than in those with myopericarditis (11%) or perimyocarditis (12%; P<0.001). Troponin elevation was not associated with an increase in complications.

CONCLUSIONS

The outcome of myopericardial inflammatory syndromes is good. Unlike acute coronary syndromes, troponin elevation is not a negative prognostic marker in this setting.