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

Impact of cannabidiol on myocardial recovery in patients with acute myocarditis: Rationale & design of the ARCHER trial

AIMS

Acute myocarditis, although a rare disease, can be associated with sudden cardiac death or the need for transplantation in both children and young adults. To date, there is no definitive evidence to support the routine use of immunosuppressive therapy or treatment targeting inflammation in patients with myocarditis. Animal models of cardiovascular (CV), as well as neurological diseases, have demonstrated that cannabidiol has significant anti-inflammatory properties and may represent a promising therapy in acute myocarditis. This efficacy has been shown in a murine model of autoimmune myocarditis as well as in in vitro and in vivo models of heart failure (HF).

METHODS AND RESULTS

We present the rationale and design of the ARCHER Trial, an international multicentre, double-blind, randomized, placebo-controlled, phase II study examining the safety and efficacy of a pharmaceutically produced cannabidiol formulation, in patients with mild to moderate acute myocarditis. Eligible patients are those with acute myocarditis, randomized within 10 days of the diagnostic cardiac MRI (CMR), which has met defined diagnostic criteria for myocarditis. Oral treatment (cannabidiol or placebo) is titrated from 2.5 mg/kg of body weight up to 10 mg/kg of body weight b.i.d. (or highest tolerated dose) and taken for 12 weeks in addition to standard of care therapy for HF. The primary endpoints are defined as changes in global longitudinal strain (GLS) and extra cellular volume (ECV), measured by CMR at 12 weeks. Assuming 80% power, a 5% alpha risk and 25% missing CMR follow-up data at Week 12, 100 patients are required to demonstrate the desired treatment effect of 18%. The change in left ventricular ejection fraction (LVEF) from baseline to Week 12 was selected as the secondary endpoint. Additional exploratory endpoints include changes in hs-troponin, NT-proBNP, markers of inflammation and endothelial function during the 12-week treatment period. The trial is ongoing but is now more than 50% recruited. As enrolment in the trial continues, no interim data are available for inclusion in this Design paper.

CONCLUSIONS

The ongoing ARCHER Trial is an international, multicentre, double-blind, randomized, placebo-controlled phase II study, designed to determine the effect of a pharmaceutically produced cannabidiol formulation on CMR parameters in patients presenting with acute myocarditis. Enrolment of 100 patients is expected to conclude in Q3 2024. Study results will be available in early 2025.

Sex- specific differences in suspected myocarditis presentations and outcomes

BACKGROUND

Signs and symptoms of myocarditis may vary among men and women.

OBJECTIVES

This study aimed to analyze sex-specific differences in the presentation and outcomes of patients with suspected myocarditis.

METHODS

Patients meeting clinical ESC criteria for suspected myocarditis were included from two tertiary centers between 2002 and 2021. Baseline characteristics, cardiac magnetic resonance (CMR), and outcomes (i.e. major adverse cardiovascular events (MACE), including all-cause death, ventricular tachycardia, hospitalization for heart failure, and recurrent myocarditis) in women and men were compared.

RESULTS

776 consecutive patients (mean age 48 ± 16 years, 286 [36.9 %] women) were followed for a median of 3.7 years. Compared to men, women presented more often with severe dyspnea (NYHA III-IV: 25.9 % versus 19.2 % of men; p = 0.029), while chest pain was more frequent in men (39.8 % versus 32.2 % in women; p = 0.037). There was no difference in left ventricular ejection fraction at the time of presentation (women: 48.5 ± 15.4 % versus men: 48.6 ± 15.1 %;p = 0.954). Further, no sex-specific difference in the occurrence of MACE was noted; however, women were more often hospitalized for heart failure than men (women: 9.8 % versus men: 5.3 %, p = 0.018). Accordingly, female sex was independently associated with heart failure hospitalization in an adjusted model (HR: 2.31, 95 % CI:1.25-4.26; p = 0.007). The prognostic value of CMR markers was similar in both sex.

CONCLUSION

Significant sex-specific differences in presentations and imaging findings are found in patients with suspected myocarditis. Female sex is associated with a twofold increase in the risk of heart failure hospitalization, which should be considered in risk stratification.

Sex and Age Characteristics in Acute or Chronic Myocarditis A Descriptive, Multicenter Cohort Study

BACKGROUND

Understanding the clinical features of myocarditis in various age groups is required to identify age-specific disease patterns.

OBJECTIVES

The objective of this study was to examine differences in sex distribution and clinical outcomes in patients with myocarditis of various ages.

METHODS

Patients with acute or chronic myocarditis in 3 centers in Berlin, Germany from 2005 to 2021 and in the United States (National Inpatient Sample) from 2010 to 2019 were included. Age groups examined included "prepubescent" (below 11 years for females and below 13 years for males), adolescents (11 [female] or 13 [male] to 18 years), young adults (18-35 years), "middle-aged adults" (35-54 years), and older adults (age >54 years). In patients admitted to the hospital, hospital mortality, length of stay, and medical complication rates were examined.

RESULTS

Overall, 6,023 cases in Berlin and 9,079 cases in the U.S. cohort were included. In both cohorts, there were differences in sex distribution among the 5 age categories, and differences in the distribution were most notable in adolescents (69.3% males vs 30.7% females) and in young adults (73.8% males vs 26.3% females). Prepubescent and older adults had the highest rates of in-hospital mortality, hospital length of stay, and medical complications. In the Berlin cohort, prepubescent patients had higher levels of leukocytes (P < 0.001), antistreptolysin antibody (P < 0.001), and NT-proBNP (P < 0.001) when compared to young adults.

CONCLUSIONS

In this study, we found that sex differences in myocarditis and clinical features of myocarditis were age-dependent.

Exercise After Acute Myocarditis: When and How to Return to Sports

Myocarditis is an inflammatory disease of the myocardium secondary to infectious and noninfectious insults. The most feared consequence of myocarditis is sudden cardiac death owing to electrical instability and arrhythmia. Typical presenting symptoms include chest pain, dyspnea, palpitations and/or heart failure. Diagnosis is usually made with history, electrocardiogram, biomarkers, echocardiogram, and cardiac MRI (CMR). Application of the Lake Louise criteria to CMR results can help identify cases of myocarditis. Treatment is usually supportive with medical therapy, and patients are recommended to abstain from exercise for 3 to 6 months. Exercise restrictions may be lifted after normalization on follow-up testing.

Post-acute midterm follow-up cardiac MRI findings and clinical outcomes in patients with COVID-19 vaccine-associated myocarditis: a comprehensive systematic review and meta-analysis

PURPOSE

Although previous investigations revealed favourable in-hospital outcomes of COVID-19 vaccine-related myocarditis, the mid-term prognosis is still unclear. Hence, we aim to summarise existing evidence on the follow-up imaging and clinical findings in patients with COVID-19 vaccine-related myocarditis.

METHODS

We performed a systematic search in online databases using relevant key terms covering COVID-19 vaccine, myocarditis, follow-up, and cardiac MRI. We included all observational studies that reported cardiac MRI findings of patients with myocarditis following COVID-19 vaccination in both acute and follow-up phases. Data on clinical outcomes and cardiac MRI findings were extracted and pooled using a random-effect model.

RESULTS

A total of 27 studies (126 patients) met our eligibility criteria. At the time of follow-up, myocarditis symptoms were resolved in all patients, but abnormal electrocardiography and elevated troponin levels were detected in 18.7% and 3.8% of them, respectively. Median imaging follow-up times varied from 3 to 6.3 months. On follow-up cardiac MRI, the persistence of LGE was observed in 76% (95%CI: 62 to 85%), but its extension declined compared to the baseline in almost all patients. Persistent LGE was accompanied by myocardial edoema in six patients, and it was consistent with myocardial fibrosis (LGE without edoema) in the remaining cases. Mean changes (95%CI) of cardiac MRI left ventricular ejection fraction (LVEF) (%) was +2.97 (+1.59 to +4.34) from baseline.

CONCLUSION

In conclusion, although most patients likely experience favourable clinical outcomes without serious complications, cardiac MRI abnormalities, mainly LGE, may persist in a notable proportion of them beyond the acute phase.

Optimal timing of follow-up cardiac magnetic resonance in patients with uncomplicated acute myocarditis

BACKGROUND

Cardiac magnetic resonance (CMR) is central in the diagnosis and prognostic stratification of acute myocarditis (AM) but the timing of repeated CMR scans to assess edema resolution and late gadolinium enhancement (LGE) stabilization remain unclear. We assessed edema and LGE evolution over 12 months to identify the optimal timing of repeat CMR evaluation in AM.

METHODS AND RESULTS

Thirty-three consecutive patients with AM underwent CMR at clinical presentation (CMR-1), after 3 months (CMR-2) and after 12-months (CMR-3). CMR included assessment of edema and LGE, left ventricular ejection fraction (LVEF) and left ventricular mass index (LVMi). After CMR-3 patients were followed-up every three-months by clinical evaluation, Holter-monitoring, and echocardiography. All patients had edema and LGE at CMR-1. At CMR-2 edema-positive segments (0.42 ± 0.34 vs. 3.18 ± 2.33, p < 0.005), LGE (4.98 ± 4.56 vs. 9.60 ± 8.58 g, and 4.22 ± 3.97% vs 7.50 ± 5.61%) and LVMi (69.82 ± 11.83 vs 76.06 ± 13.13 g/m2) (all p < 0.0001) significantly reduced, while LVEF (63.12 ± 5.47% vs.61.15 ± 6.87% p < 0.05) significantly improved, compared to CMR-1. At CMR-2 edema persisted in 7 patients (21%) but resolved at CMR-3 with no further changes of LVMi, LVEF and LGE. During follow-up (85 ± 15 months), 5 (15%) patients showed persistent ventricular arrhythmias. Univariate predictors of arrhythmic persistence were LGE extension at CMR-2 and CMR-3 (both p < 0.05), but not at CMR-1 (p = 0.07).

CONCLUSIONS

Most patients with uncomplicated AM show edema resolution with LGE stabilization after 3 months. Further CMR evaluations should be limited to patients with persisting edema at this time. LGE extent measured after edema resolution is associated with persistent ventricular arrhythmias.

Red Flags in Acute Myocarditis

Acute myocarditis is an inflammatory disease of the heart that may occur in the setting of infection, immune system activation or exposure to certain drugs. Often, it is caused by viruses, whereby the clinical course is usually benign; however, it may also present with rapidly progressive fulminant myocarditis, which is associated with high morbidity and mortality. This review highlights the critical red flags - from the clinical, biochemical, imaging and histopathological perspectives - that should raise the index of suspicion of acute myocarditis. We also present an illustrative case of a young female patient with rapidly progressive cardiogenic shock requiring veno-arterial extracorporeal membrane oxygenation as a bridge to orthotopic heart transplantation. The patient showed no clinical or echocardiographic recovery signs and eventually underwent orthotopic heart transplantation. Furthermore, we elaborate on the classifications of acute myocarditis based on clinical presentation and histopathology classifications, focusing on identifying key red flags that will inform early diagnosis and appropriate management in such challenging cases.

Mid- to long-term cardiac magnetic resonance findings in elite athletes recovered from COVID-19: results from an ongoing observational COVID-19 study at a German Olympic medical centre

INTRODUCTION

The cardiac magnetic resonance (CMR) data on mid- to long-term myocardial damage due to COVID-19 infections in elite athletes are scarce. Therefore, this study investigated the mid -to long-term consequences of myocardial involvement after a COVID-19 infection in elite athletes.

MATERIALS AND METHODS

This study included 27 athletes at the German Olympic Centre North Rhine-Westphalia (NRW)/Rhineland with a confirmed previous COVID-19 infection between January 2020 and October 2021. The athletes were part of an ongoing observational COVID-19 study at the Institute of Cardiology and Sports Medicine Cologne at the German Sport University (DSHS).Nine healthy non-athletes with no prior COVID-19 illness served as controls. CMR was performed within a mean of 182 days (standard deviation [SD] 99) of the initial positive test result.

RESULTS

CMR did not reveal any signs of acute myocarditis (according to the current Lake Louise criteria) or myocardial damage in any of the 26 elite athletes with previous COVID-19 infection. Of these athletes, 92% experienced a symptomatic course, and 54% reported symptoms lasting for more than 4 weeks. One male athlete was excluded from the analysis because CMR revealed an arrhythmogenic right ventricular cardiomyopathy (ARVC). Athletes had significantly enlarged left and right ventricle volumes and increased left ventricular myocardial mass in comparison to the healthy control group (LVEDVi 103.4 vs 91.1 ml/m2, p = 0.031; RVEDVi 104.1 vs 86.6 ml/m2, p = 0.007; LVMi 59.0 vs 46.2 g/m2, p = 0.002). Only two cases of elevated high-sensitivity-Troponin were documented; in one, the participant had previously engaged in high-intensity training, and in the other, CMR revealed a diagnosis of an arrhythmogenic cardiomyopathy.

CONCLUSION

Our findings suggest that the risk for mid- to long-term myocardial damage is very low to negligible in elite athletes. Our results do not allow conclusions to be drawn regarding myocardial injury in the acute phase of infection nor about possible long-term myocardial effects in the general population.

Cardiac magnetic resonance biomarkers as surrogate endpoints in cardiovascular trials for myocardial diseases

Cardiac magnetic resonance offers multiple facets in the diagnosis, risk stratification, and management of patients with myocardial diseases. Particularly, its feature to precisely monitor disease activity lends itself to quantify response to novel therapeutics. This review critically appraises the value of cardiac magnetic resonance imaging biomarkers as surrogate endpoints for prospective clinical trials. The primary focus is to comprehensively outline the value of established cardiac magnetic resonance parameters in myocardial diseases. These include heart failure, cardiac amyloidosis, iron overload cardiomyopathy, hypertrophic cardiomyopathy, cardio-oncology, and inflammatory cardiomyopathies like myocarditis and sarcoidosis.

Significant exercise limitations after recovery from MIS-C related myocarditis

BACKGROUND

Myocarditis is one of the presentations of multisystemic inflammatory syndrome in children (MIS-C) following coronavirus disease 2019 (COVID-19). Although the reported short-term prognosis is good, data regarding medium-term functional capacity and limitations are scarce. This study aimed to evaluate exercise capacity as well as possible cardiac and respiratory limitations in children recovered from MIS-C related myocarditis.

METHODS

Fourteen patients who recovered from MIS-C related myocarditis underwent spirometry and cardiopulmonary exercise testing (CPET), and their results were compared with an age-, sex-, weight- and activity level-matched healthy control group (n = 14).

RESULTS

All participants completed the CPET with peak oxygen uptake (peak [Formula: see text]), and the results were within the normal range (MIS-C 89.3% ± 8.9% and Control 87.9% ± 13.7% predicted [Formula: see text]). Five post-MIS-C patients (35%) had exercise-related cardio-respiratory abnormalities, including oxygen desaturation and oxygen-pulse flattening, compared to none in the control group. The MIS-C group also had lower peak exercise saturation (95.6 ± 3.5 vs. 97.6 ± 1.1) and lower breathing reserve (17.4% ± 7.5% vs. 27.4% ± 14.0% of MVV).

CONCLUSIONS

Patients who recovered from MIS-C related myocarditis may present exercise limitations. Functional assessment (e.g., CPET) should be included in routine examinations before allowing a return to physical activity in post-MIS-C myocarditis. Larger, longer term studies assessing functional capacity and focusing on physiological mechanisms are needed.

Cardiovascular magnetic resonance (CMR) and positron emission tomography (PET) imaging in the diagnosis and follow-up of patients with acute myocarditis and chronic inflammatory cardiomyopathy : A review paper with practical recommendations on behalf of the European Society of Cardiovascular Radiology (ESCR)

Advanced cardiac imaging techniques such as cardiovascular magnetic resonance (CMR) and positron emission tomography (PET) are widely used in clinical practice in patients with acute myocarditis and chronic inflammatory cardiomyopathies (I-CMP). We aimed to provide a review article with practical recommendations from the European Society of Cardiovascular Radiology (ESCR), in order to guide physicians in the use and interpretation of CMR and PET in clinical practice both for acute myocarditis and follow-up in chronic forms of I-CMP.

Sex differences in coronavirus disease 2019 myocarditis

Myocarditis is frequently caused by viral infections, but animal models that closely resemble human disease suggest that virus-triggered autoimmune disease is the most likely cause of myocarditis. Myocarditis is a rare condition that occurs primarily in men under age 50. The incidence of myocarditis rose at least 15x during the COVID-19 pandemic from 1-10 to 150-400 cases/100,000 individuals, with most cases occurring in men under age 50. COVID-19 vaccination was also associated with rare cases of myocarditis primarily in young men under 50 years of age with an incidence as high as 50 cases/100,000 individuals reported for some mRNA vaccines. Sex differences in the immune response to COVID-19 are virtually identical to the mechanisms known to drive sex differences in myocarditis pre-COVID based on clinical studies and animal models. The many similarities between COVID-19 vaccine-associated myocarditis to COVID-19 myocarditis and non-COVID myocarditis suggest common immune mechanisms drive disease.

Case report: Recurrence of inflammatory cardiomyopathy detected by magnetocardiography

Background

The diagnosis of inflammatory cardiomyopathies remains challenging. Life-threatening conditions such as acute coronary syndrome (ACS) always have to be considered as differential diagnoses due to similarities in presentation. Diagnostic methods for inflammatory cardiomyopathy include endomyocardial biopsy (EMB), cardiac magnetic resonance imaging (CMR), and positron emission tomography-computed tomography (PET-CT). We report a case in whom magnetocardiography (MCG) led to an initial diagnosis of inflammatory cardiomyopathy and in whom MCG was used for subsequent monitoring of treatment response under immunosuppression.

Case presentation

A 53-year-old man presented with two recurrent episodes of inflammatory cardiomyopathy within a 2-year period. The patient initially presented with reduced exercise capacity. Echocardiography revealed a moderately reduced left ventricular ejection fraction (LVEF 40%). Coronary angiography ruled out obstructive coronary artery disease (CAD) and an EMB was performed. The EMB revealed inflammatory cardiomyopathy without viral pathogens or replication. Moreover, we performed MCG, which confirmed a pathological Tbeg-Tmax vector of 0.108. We recently established a cutoff value of Tbeg-Tmax of 0.051 or greater for the diagnosis of inflammatory cardiomyopathy. Immunosuppressive therapy with prednisolone was initiated, resulting in clinical improvement and an LVEF increase from 40% to 45% within 1 month. Furthermore, the MCG vector improved to 0.036, which is considered normal based on our previous findings. The patient remained clinically stable for 23 months. During a routine follow-up, MCG revealed an abnormal Tbeg-Tmax vector of 0.069. The patient underwent additional testing including routine laboratory values, echocardiography (LVEF 35%), and PET-CT. PET-CT revealed increased metabolism in the myocardium-primarily in the lateral wall. Therapy with prednisolone and azathioprine was initiated and MCG was used to monitor the effect of immunosuppressive therapy.

Conclusion

In addition to diagnostic screening, MCG has the potential to become a valuable method for surveillance monitoring of patients who have completed treatment for inflammatory cardiomyopathy. Furthermore, it could be used for treatment monitoring. While changes in the magnetic vector of the heart are not specific to inflammatory cardiomyopathy, as they may also occur in other types of cardiomyopathies, MCG offers a tool of broad and efficient diagnostic screening for cardiac pathologies without side effects.

COVID-19, Myocarditis and Pericarditis

Viral infections are a leading cause of myocarditis and pericarditis worldwide, conditions that frequently coexist. Myocarditis and pericarditis were some of the early comorbidities associated with SARS-CoV-2 infection and COVID-19. Many epidemiologic studies have been conducted since that time concluding that SARS-CoV-2 increased the incidence of myocarditis/pericarditis at least 15× over pre-COVID levels although the condition remains rare. The incidence of myocarditis pre-COVID was reported at 1 to 10 cases/100 000 individuals and with COVID ranging from 150 to 4000 cases/100 000 individuals. Before COVID-19, some vaccines were reported to cause myocarditis and pericarditis in rare cases, but the use of novel mRNA platforms led to a higher number of reported cases than with previous platforms providing new insight into potential pathogenic mechanisms. The incidence of COVID-19 vaccine-associated myocarditis/pericarditis covers a large range depending on the vaccine platform, age, and sex examined. Importantly, the findings highlight that myocarditis occurs predominantly in male patients aged 12 to 40 years regardless of whether the cause was due to a virus-like SARS-CoV-2 or associated with a vaccine-a demographic that has been reported before COVID-19. This review discusses findings from COVID-19 and COVID-19 vaccine-associated myocarditis and pericarditis considering the known symptoms, diagnosis, management, treatment, and pathogenesis of disease that has been gleaned from clinical research and animal models. Sex differences in the immune response to COVID-19 are discussed, and theories for how mRNA vaccines could lead to myocarditis/pericarditis are proposed. Additionally, gaps in our understanding that need further research are raised.

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.

Association between ECG parameters and late gadolinium enhancement along the course of myocarditis

PURPOSE

Numerous electrocardiogram (ECG) abnormalities and late gadolinium enhancement (LGE) in cardiac magnetic resonance imaging (CMR) have been related to poor prognosis in acute myocarditis. We evaluated whether ECG parameters are associated with the distribution and dynamic of LGE along the course of myocarditis.

METHODS

Fifty-one patients with CMR confirmed acute myocarditis were included who underwent CMR with LGE and 12-lead ECG at baseline and 3-month follow-up at our institution. The association between the presence, regional distribution and change of ECG parameters and LGE was investigated using linear regression analysis. LGE was quantified as visual presence score (VPS) and visual transmurality score (VTS).

RESULTS

Among many ECG parameters only > 1 mm ST-elevation (STE) was associated with VPS and VTS at baseline (β = 3.08 [95%CI: 1.75; 4.41], p = < 0.001 and β = 5.40 [95%CI: 1.92; 8.88], p = 0.004; respectively). STE was most frequent in lateral and inferior ECG-leads (48% and 31%) and it was associated with VPS and VTS in these localizations (p < 0.05 all), however no association between anterior-septal STE and LGE could be confirmed. At follow-up the regression of STE was associated with the regression of VPS and VTS in univariate analysis (β=-1.49 [95%CI: -2.41; -0.57], p = 0.003 and β=-4.87 [95%CI: -7.18; -2.56], p = 0.001, respectively), which remained significant for VTS using a multivariate model (β=-2.39 [95%CI: -3.32; -0.47], p = 0.019).

CONCLUSION

Although we demonstrated some promising associations between STE and LGE, the usability of ECG to estimate the territorial involvement and dynamical changes of LGE along the course of myocarditis is generally limited and cardiac magnetic resonance should be considered for this purpose.

Application of Magnetocardiography to Screen for Inflammatory Cardiomyopathy and Monitor Treatment Response

Background Inflammatory cardiomyopathy is one of the most common causes of sudden cardiac death in young adults. Diagnosis of inflammatory cardiomyopathy remains challenging, and better monitoring tools are needed. We present magnetocardiography as a method to diagnose myocardial inflammation and monitor treatment response. Methods and Results A total of 233 patients were enrolled, with a mean age of 45 (±18) years, and 105 (45%) were women. The primary analysis included 209 adult subjects, of whom 66 (32%) were diagnosed with inflammatory cardiomyopathy, 17 (8%) were diagnosed with cardiac amyloidosis, and 35 (17%) were diagnosed with other types of nonischemic cardiomyopathy; 91 (44%) did not have cardiomyopathy. The second analysis included 13 patients with inflammatory cardiomyopathy who underwent immunosuppressive therapy after baseline magnetocardiography measurement. Finally, diagnostic accuracy of magnetocardiography was tested in 3 independent cohorts (total n=23) and 1 patient, who developed vaccine-related myocarditis. First, we identified a magnetocardiography vector to differentiate between patients with cardiomyopathy versus patients without cardiomyopathy (vector of ≥0.051; sensitivity, 0.59; specificity, 0.95; positive predictive value, 93%; and negative predictive value, 64%). All patients with inflammatory cardiomyopathy, including a patient with mRNA vaccine-related myocarditis, had a magnetocardiography vector ≥0.051. Second, we evaluated the ability of the magnetocardiography vector to reflect treatment response. We observed a decrease of the pathologic magnetocardiography vector toward normal in all 13 patients who were clinically improving under immunosuppressive therapy. Magnetocardiography detected treatment response as early as day 7, whereas echocardiographic detection of treatment response occurred after 1 month. The magnetocardiography vector decreased from 0.10 at baseline to 0.07 within 7 days (P=0.010) and to 0.03 within 30 days (P<0.001). After 30 days, left ventricular ejection fraction improved from 42.2% at baseline to 53.8% (P<0.001). Conclusions Magnetocardiography has the potential to be used for diagnostic screening and to monitor early treatment response. The method is valuable in inflammatory cardiomyopathy, where there is a major unmet need for early diagnosis and monitoring response to immunosuppressive therapy.

Exercise After Acute Myocarditis: When and How to Return to Sports

Myocarditis is an inflammatory disease of the myocardium secondary to infectious and noninfectious insults. The most feared consequence of myocarditis is sudden cardiac death owing to electrical instability and arrhythmia. Typical presenting symptoms include chest pain, dyspnea, palpitations and/or heart failure. Diagnosis is usually made with history, electrocardiogram, biomarkers, echocardiogram, and cardiac MRI (CMR). Application of the Lake Louise criteria to CMR results can help identify cases of myocarditis. Treatment is usually supportive with medical therapy, and patients are recommended to abstain from exercise for 3 to 6 months. Exercise restrictions may be lifted after normalization on follow-up testing.

Cardiac MRI with late gadolinium enhancement shows cardiac involvement 3-6 months after severe acute COVID-19 similar to or worse than PIMS

Background

Coronavirus disease 2019 (COVID-19) in children is rarely severe. However, severe courses occur, especially in the presence of risk factors. A minority of children develop pediatric inflammatory multisystem syndrome (PIMS) with substantial morbidity. While the importance of cardiac involvement after PIMS is well established, its role after severe acute COVID-19 remains unclear. We aim to compare cardiac sequelae of children after severe acute COVID-19 using cardiac MRI and compare them with patients after PIMS.

Methods

For this prospective cohort study, we recruited patients with acute COVID or PIMS in a single center. Clinical follow-up, lab work, ECG, and echocardiography were done within 2 days after disease onset and 3-6 months after discharge. At the last visit 3-6 months later, cardiac MRI (CMR) with late gadolinium enhancement (LGE) was performed to evaluate cardiac sequelae and compare both groups.

Results

Data were obtained from n = 14 patients with PIMS and n = 7 patients with severe acute COVID-19. At the start of the respective disease, left ventricular (LV) ejection fraction was reduced in seven patients with PIMS but none in the acute COVID-19 group. Transient mitral valve insufficiency was present in 38% of patients, of whom PIMS accounted for 7/8 cases. Eight patients (38%) with PIMS presented coronary artery abnormalities, with normalization in 7/8 patients. A significant decrease in LV mass index 3-6 months after disease onset was observed in both groups. MRI follow-up revealed non-ischemic myocardial pattern of LGE in 12/21 patients- in all (6/6) after severe acute COVID-19 and in less than half (6/14) after PIMS. Normal body weight-adjusted stroke volumes and end-diastolic volumes were found in 20/21 patients.

Conclusions

We show that children suffering from severe acute COVID-19 have a similar, or worse, cardiac risk profile as patients with PIMS. Both patient groups should therefore receive close pediatric cardiac follow-up examinations. Cardiac MRI is the technique of choice, as most patients presented with delayed LGE as a sign of persistent cardiac injury despite normalization of laboratory and echocardiographic findings.

Impact of myocardial injury on regional left ventricular function in the course of acute myocarditis with preserved ejection fraction: insights from segmental feature tracking strain analysis using cine cardiac MRI

The aim of this study was to provide insights into myocardial adaptation over time in myocyte injury caused by acute myocarditis with preserved ejection fraction. The effect of myocardial injury, as defined by the presence of late gadolinium enhancement (LGE), on the change of left ventricular (LV) segmental strain parameters was evaluated in a longitudinal analysis. Patients with a first episode of acute myocarditis were enrolled retrospectively. Peak radial (PRS), longitudinal (PLS) and circumferential (PCS) LV segmental strain values at baseline and at follow-up were computed using feature tracking cine cardiac magnetic resonance imaging. The change of segmental strain values in LGE positive (LGE+) and LGE negative (LGE-) segments was compared over a course of 89 ± 20 days. In 24 patients, 100 LGE+ segments and 284 LGE- segments were analysed. Between LGE+ and LGE- segments, significant differences were found for the change of segmental PCS (p < 0.001) and segmental PRS (p = 0.006). LGE + segments showed an increase in contractility, indicating recovery, and LGE- segments showed a decrease in contractility, indicating normalisation after a hypercontractile state or impairment of an initially normal contracting segment. No significant difference between LGE+ and LGE- segments was found for the change in segmental PLS. In the course of acute myocarditis with preserved ejection fraction, regional myocardial function adapts inversely in segments with and without LGE. As these effects seem to counterbalance each other, global functional parameters might be of limited use in monitoring functional recovery of these patients.

[Dermatomyositis and juvenile dermatomyositis]

Dermatomyositis (DM) is an inflammatory multisystem disease of unknown etiology, which can already occur in children but first onset can also be in older adulthood. Myalgia and muscle weakness can occur later in the course of the disease or even be completely absent in some forms. Classical signs on the skin include heliotrope rash, facial erythema, Gottron's papules and nailfold capillary abnormalities. For the diagnosis, screening for the presence of myositis-specific autoantibodies has become increasingly more relevant. Muscle enzymes may be elevated but not in approximately one third of patients. In the absence of typical clinical or serologic findings, additional examination methods such as nailfold capillaroscopy, magnetic resonance imaging, electromyography, skin or muscle biopsies may help to establish the diagnosis. Depending on the clinical and serological subtype, additional screening for gastrointestinal or cardiopulmonary involvement should be considered. In adults, an age-appropriate tumor screening should also be performed. Apart from corticosteroids as induction therapy, biologics and small molecule inhibitors are gaining in importance in addition to conventional disease-modifying anti-rheumatic drugs and intravenous immunoglobulins. The prognosis for DM and juvenile DM (JDM) has improved. Most patients recover at least to some extent; however, a few patients die and a minority develop persisting muscle atrophy or severe calcinosis.

Role of cardiac magnetic resonance imaging in troponinemia syndromes

Cardiac magnetic resonance imaging (MRI) is an evolving technology, proving to be a highly accurate tool for quantitative assessment. Most recently, it has been increasingly used in the diagnostic and prognostic evaluation of conditions involving an elevation in troponin or troponinemia. Although an elevation in troponin is a nonspecific marker of myocardial tissue damage, it is a frequently ordered investigation leaving many patients without a specific diagnosis. Fortunately, the advent of newer cardiac MRI protocols can provide additional information. In this review, we discuss several conditions associated with an elevation in troponin such as myocardial infarction, myocarditis, Takotsubo cardiomyopathy, coronavirus disease 2019 related cardiac dysfunction and athlete’s heart syndrome.

Cardiac magnetic resonance findings in acute myocarditis after mRNA COVID-19 vaccination

There is increasing evidence for myocarditis as a complication of the mRNA coronavirus disease 2019 (COVID-19) vaccination. We report the case of a 20-year-old previously healthy man who presented with fever and chest pain 2 days after the second dose of mRNA-1273 vaccine. Electrocardiogram and laboratory studies showed extensive ST-segment elevation accompanied by elevated cardiac biomarkers. Cardiac magnetic resonance (CMR) revealed late gadolinium enhancement (LGE) characteristics of myocarditis. The patient rapidly improved with conservative management and was discharged on hospital day 6. As an advantage over previous reports, we performed a 1-month follow-up CMR. It showed improvement in myocardial edema but persistence of LGE which may indicate irreversible fibrosis. CMR may be useful not only for diagnosis but also for prognostic evaluation of myocarditis after COVID-19 mRNA vaccination.

<Learning objective: With the expansion of coronavirus disease 2019 (COVID-19) vaccine administration, the number of cases of myocarditis as a complication has been increasing. Cardiac magnetic resonance imaging can be useful for the diagnosis and follow-up of patients with myocarditis after mRNA COVID-19 vaccination. Persistent late gadolinium enhancement may indicate irreversible myocardial fibrosis, and it is also associated with poor prognosis, similar to previously reported cases of other acute myocarditis.>

Case report: Myocarditis with nonsustained ventricular tachycardia following COVID-19 mRNA vaccination in a female adolescent

Children with underlying medical conditions potentially develop severe illness from Coronavirus disease 2019 (COVID-19). The use of vaccines against COVID-19 is currently recommended for the pediatric population. The COVID-19 vaccine has a temporal association with the occurrence of myocarditis. Although most patients with COVID-19 vaccination-associated myocarditis (C-VAM) exhibit a mild clinical course and rapid recovery, C-VAM potentially causes electrical instability and sudden cardiac death. Herein, we report the case of a 17-year-old woman who presented with chest pain and syncope following the first dose of the messenger RNA COVID-19 vaccine. The patient's heart function was impaired, and nonsustained ventricular tachycardia was frequent. Cardiac magnetic resonance (CMR) imaging satisfied the criteria for myocarditis. Despite the administration of immunomodulatory drugs, the patient's heart function was not fully restored, and the concentration of cardiac enzymes remained above the normal range. Persistence of late gadolinium enhancement was observed on short-term follow-up CMR imaging. Although most patients with C-VAM exhibit mild symptoms, significant cardiac arrhythmias potentially occur. Furthermore, some patients with C-VAM demonstrate prolonged impaired heart function and sustained late gadolinium enhancement on follow-up CMR imaging. Therefore, monitoring of electrical and functional cardiac abnormalities in patients with C-VAM is crucial and the long-term outcomes and prognosis of patients with C-VAM require further investigation.

Multiparametric Cardiovascular Magnetic Resonance Approach in Diagnosing, Monitoring, and Prognostication of Myocarditis

Myocarditis represents the entity of an inflamed myocardium and is a diagnostic challenge caused by its heterogeneous presentation. Contemporary noninvasive evaluation of patients with clinically suspected myocarditis using cardiac magnetic resonance (CMR) includes dimensions and function of the heart chambers, conventional T2-weighted imaging, late gadolinium enhancement, novel T1 and T2 mapping, and extracellular volume fraction calculation. CMR feature-tracking, texture analysis, and artificial intelligence emerge as potential modern techniques to further improve diagnosis and prognostication in this clinical setting. This review will describe the evidence surrounding different CMR methods and image postprocessing methods and highlight their values for clinical decision making, monitoring, and risk stratification across stages of this condition.

More than 50% of Persistent Myocardial Scarring at One Year in "Infarct-like" Acute Myocarditis Evaluated by CMR

BACKGROUND

Cardiac magnetic resonance (CMR) has emerged as a reference tool for the non-invasive diagnosis of myocarditis. However, its role in follow-up (FU) after the acute event is unclear. The objectives were to assess the evolution of CMR parameters between the acute phase of infarct-like myocarditis and 12 months thereafter and to identify the predictive factors of persistent myocardial scarring at one year.

METHODS

All patients with infarct-like acute myocarditis confirmed by CMR were included. CMR was performed within 8 days following symptom onset, at 3 months and at one year. One-year FU included ECG, a cardiac stress test, Holter recording, biological assessments, medical history and a quality-of-life questionnaire. Patients were classified according to the presence or absence of complete recovery at one year based on the CMR evaluation.

RESULTS

A total of 174 patients were included, and 147 patients had three CMR. At one year, 79 patients (54%) exhibited persistent myocardial scarring on CMR. A multivariate analysis showed that high peak troponin at the acute phase (OR: 3.0-95%CI: 1.16-7.96-p = 0.024) and the initial extent of late gadolinium enhancement (LGE) (OR: 1.1-95%CI: 1.03-1.19-p = 0.006) were independent predictors of persistent myocardial scarring. Moreover, patients with myocardial scarring on the FU CMR were more likely to have premature ventricular contractions during the cardiac stress test (25% versus 9%, p = 0.008).

CONCLUSION

Less than 50% of patients with infarct-like acute myocarditis showed complete recovery at one year. Although major adverse cardiac events were rare, ventricular dysrhythmias at one year were more frequent in patients with persistent myocardial scarring.

Recurrent Chest Pain after COVID-19: Diagnostic Utility of Cardiac Magnetic Resonance Imaging

We report a case of myocarditis in an adult patient with recent coronavirus disease 2019 (COVID-19) infection presenting as recurrent ST-segment elevation, mimicking coronary vasospasm. This case highlights the wide range of presentations of COVID-19–related myocarditis. The novel teaching point is that COVID-19 myocarditis can present with acute manifestations such as chest pain and transient ST-segment elevation even several weeks after complete recovery from the initial infection. Cardiac magnetic resonance imaging should be considered in patients with chest pain syndromes and angiographically normal coronary arteries, as the presence of late gadolinium enhancement and a high T2 signal can be diagnostic. Follow-up cardiac magnetic resonance imaging may be used to assess resolution.

COVID-19-Myocarditis and Return to Play: Reflections and Recommendations From a Canadian Working Group

The COVID-19-related pandemic has resulted in profound health, financial, and societal impacts. Organized sporting events, from recreational to the Olympic level, have been cancelled to both mitigate the spread of COVID-19 and protect athletes and highly active individuals from potential acute and long-term infection-associated harms. COVID-19 infection has been associated with increased cardiac morbidity and mortality. Myocarditis and late gadolinium enhancement as a result of COVID-19 infection have been confirmed. Correspondingly, myocarditis has been implicated in sudden cardiac death of athletes. A pragmatic approach is required to guide those who care for athletes and highly active persons with COVID-19 infection. Members of the Community and Athletic Cardiovascular Health Network (CATCHNet) and the writing group for the Canadian Cardiovascular Society/Canadian Heart Rhythm Society Joint Position Statement on the Cardiovascular Screening of Competitive Athletes recommend that highly active persons with suspected or confirmed COVID-19 infection refrain from exercise for 7 days after resolution of viral symptoms before gradual return to exercise. We do not recommend routine troponin testing, resting 12-lead electrocardiography, echocardiography, or cardiac magnetic resonance imaging before return to play. However, medical assessment including history and physical examination with consideration of resting electrocardiography and troponin can be considered in the athlete manifesting new active cardiac symptoms or a marked reduction in fitness. If concerning abnormalities are encountered at the initial medical assessment, then referral to a cardiologist who cares for athletes is recommended.

ACR Appropriateness Criteria® Nonischemic Myocardial Disease with Clinical Manifestations (Ischemic Cardiomyopathy Already Excluded)

Nonischemic cardiomyopathies encompass a broad spectrum of myocardial disorders with mechanical or electrical dysfunction without evidence of ischemia. There are five broad variants of nonischemic cardiomyopathies; hypertrophic cardiomyopathy (Variant 1), restrictive or infiltrative cardiomyopathy (Variant 2), dilated or unclassified cardiomyopathy (Variant 3), arrhythmogenic cardiomyopathy (Variant 4), and inflammatory cardiomyopathy (Variant 5). For variants 1, 3, and 4, resting transthoracic echocardiography, MRI heart function and morphology without and with contrast, and MRI heart function and morphology without contrast are the usually appropriate imaging modalities. For variants 2 and 5, resting transthoracic echocardiography and MRI heart function and morphology without and with contrast are the usually appropriate imaging modalities. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

Benefit of a wearable cardioverter defibrillator for detection and therapy of arrhythmias in patients with myocarditis

Aims

Myocarditis may lead to malignant arrhythmias and sudden cardiac death. As of today, there are no reliable predictors to identify individuals at risk for these catastrophic events. The aim of this study was to evaluate if a wearable cardioverter defibrillator (WCD) may detect and treat such arrhythmias adequately in the peracute setting of myocarditis.

Methods and results

In this observational, retrospective, single centre study, we reviewed patients presenting to the Charité Hospital from 2009 to 2017, who were provided with a WCD for the diagnosis of myocarditis with reduced ejection fraction (<50%) and/or arrhythmias. Amongst 259 patients receiving a WCD, 59 patients (23%) were diagnosed with myocarditis by histology. The mean age was 46 ± 14 years, and 11 patients were women (19%). The mean WCD wearing time was 86 ± 63 days, and the mean daily use was 20 ± 5 h. During that time, two patients (3%) had episodes of sustained ventricular tachycardia (VT; four total) corresponding to a rate of 28 sustained VT episodes per 100 patient‐years. Consequently, one of these patients underwent rhythm stabilization through intravenous amiodarone, while the other patient received an implantable cardioverter defibrillator. Two patients (3.4%) were found to have non‐sustained VT.

Conclusions

Using a WCD after acute myocarditis led to the detection of sustained VT in 2/59 patients (3%). While a WCD may prevent sudden cardiac death after myocarditis, our data suggest that WCD may have impact on clinical management through monitoring and arrhythmia detection.

Long-term prognosis following hospitalization for acute myocarditis - a matched nationwide cohort study

OBJECTIVE

The aim of this study was to examine the long-term risk of heart failure (HF) and all-cause mortality, in patients discharged alive following hospitalization for myocarditis. Background. Prognosis in patients with apparently uncomplicated myocarditis is in general perceived as good, but data on long-term outcomes are sparse. Methods. From nationwide Danish registries we included patients without prior cardiac disease, discharged alive with a first-time diagnosis of myocarditis 1996-2016. Patients were matched 1:10 by age- and sex, with controls from the general population. Risk of HF hospitalization and death in cases and controls was compared by use of adjusted Cox regression analyses. Results. We identified 1557 patients with a first-time diagnosis of myocarditis, 72% men, median age 39 years. Patients with myocarditis had more hypertension, diabetes, and cancer, and received more pharmacotherapy prior to hospitalization compared to matched controls. During a mean follow-up of 8.5 years, the event rate of HF hospitalization was 8.7 vs. 2.2 per 1000 patient-years (py) in cases and controls; HR 4.59 (95% CI; 3.58-5.88) and for all-cause mortality, event rate 21.9 vs 11.2 per 1000 py; HR 2.10 (95% CI; 1.82-2.43). Among 784 patients with no events or HF medication one year after diagnosis, risk of HF hospitalization (HR 2.15; 95% CI; 1.18-3.92), and all-cause mortality (HR 1.62; 95% CI; 1.21-2.16) remained elevated compared to matched controls. Conclusion. Myocarditis in younger patients without prior cardiac disease was associated with a long-term excess risk of HF hospitalization, and death, even in patients free of events and HF medication 1 year after discharge.HighlightsMyocarditis ranges from chest discomfort to severe heart failure.In most patients, left ventricular ejection fraction recovers but the long-term adverse cardiac risk is unknown.Patients with myocarditis and no prior cardiac disease were at higher risk of death and heart failureRoutine follow-up may be warranted following an episode of acute myocarditis.

Cardiac involvement in COVID-19 patients: mid-term follow up by cardiovascular magnetic resonance

BACKGROUND

Coronavirus disease 2019 (COVID-19) induces myocardial injury, either direct myocarditis or indirect injury due to systemic inflammatory response. Myocardial involvement has been proved to be one of the primary manifestations of COVID-19 infection, according to laboratory test, autopsy, and cardiovascular magnetic resonance (CMR). However, the middle-term outcome of cardiac involvement after the patients were discharged from the hospital is yet unknown. The present study aimed to evaluate mid-term cardiac sequelae in recovered COVID-19 patients by CMR METHODS: A total of 47 recovered COVID-19 patients were prospectively recruited and underwent CMR examination. The CMR protocol consisted of black blood fat-suppressed T2 weighted imaging, T2 star mapping, left ventricle (LV) cine imaging, pre- and post-contrast T1 mapping, and late gadolinium enhancement (LGE). LGE were assessed in mixed both recovered COVID-19 patients and healthy controls. The LV and right ventricle (RV) function and LV mass were assessed and compared with healthy controls.

RESULTS

A total of 44 recovered COVID-19 patients and 31 healthy controls were studied. LGE was found in 13 (30%) of COVID-19 patients. All LGE lesions were located in the mid myocardium and/or sub-epicardium with a scattered distribution. Further analysis showed that LGE-positive patients had significantly decreased LV peak global circumferential strain (GCS), RV peak GCS, RV peak global longitudinal strain (GLS) as compared to non-LGE patients (p < 0.05), while no difference was found between the non-LGE patients and healthy controls.

CONCLUSION

Myocardium injury existed in 30% of COVID-19 patients. These patients have depressed LV GCS and peak RV strains at the 3-month follow-up. CMR can monitor the COVID-19-induced myocarditis progression, and CMR strain analysis is a sensitive tool to evaluate the recovery of LV and RV dysfunction.

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.

Multiparametric cardiac magnetic resonance imaging in pediatric and adolescent patients with acute myocarditis

BACKGROUND

The diagnostic value of cardiac magnetic resonance imaging (MRI) employing the 2018 Lake Louise criteria in pediatric and adolescent patients with acute myocarditis is undefined.

OBJECTIVE

To evaluate the diagnostic value of the Lake Louise criteria in pediatric and adolescent patients with suspected acute myocarditis and to show the utility of cardiac MRI for follow-up in this patient cohort.

MATERIALS AND METHODS

Forty-three patients (age range: 8-21 years) with suspected acute myocarditis and 13 control patients who underwent cardiac MRI were retrospectively analyzed. T2-weighted and late gadolinium enhancement imaging were performed in all patients. T1 and T2 mapping were available in 26/43 patients (60%). The Lake Louise criteria were assessed. In 27/43 patients (63%), cardiac MRI follow-up was available. Receiver operating characteristic analysis, Pearson's correlation coefficient and paired Student's t-test were used for statistical analysis.

RESULTS

In the total cohort, the Lake Louise criteria achieved a sensitivity of 86% (95% confidence interval [CI]: 72-95%) and a specificity of 100% (95% CI: 79-100%) for the diagnosis of acute myocarditis. In the subgroup of patients with available mapping parameters, the diagnostic performance of the Lake Louise criteria was higher when mapping parameters were implemented into the score (area under the receiver operating characteristic curve: 0.944 vs. 0.870; P=0.033). T2 relaxation times were higher in patients with admission to the intermediate care unit and were associated with the length of intermediate care unit stay (r=0.879, P=0.049). Cardiac MRI markers of active inflammation decreased on follow-up examinations (e.g., T1 relaxation times: 1,032±39 ms vs. 975±33 ms, P<0.001; T2 relaxation times: 58±5 ms vs. 54±5 ms, P=0.003).

CONCLUSION

The Lake Louise criteria have a high diagnostic performance for the diagnosis of acute myocarditis and are a valuable tool for follow-up in pediatric and adolescent patients. The mapping techniques enhance the diagnostic performance of the 2018 Lake Louise criteria.

Myocarditis and inflammatory cardiomyopathy: current evidence and future directions

Inflammatory cardiomyopathy, characterized by inflammatory cell infiltration into the myocardium and a high risk of deteriorating cardiac function, has a heterogeneous aetiology. Inflammatory cardiomyopathy is predominantly mediated by viral infection, but can also be induced by bacterial, protozoal or fungal infections as well as a wide variety of toxic substances and drugs and systemic immune-mediated diseases. Despite extensive research, inflammatory cardiomyopathy complicated by left ventricular dysfunction, heart failure or arrhythmia is associated with a poor prognosis. At present, the reason why some patients recover without residual myocardial injury whereas others develop dilated cardiomyopathy is unclear. The relative roles of the pathogen, host genomics and environmental factors in disease progression and healing are still under discussion, including which viruses are active inducers and which are only bystanders. As a consequence, treatment strategies are not well established. In this Review, we summarize and evaluate the available evidence on the pathogenesis, diagnosis and treatment of myocarditis and inflammatory cardiomyopathy, with a special focus on virus-induced and virus-associated myocarditis. Furthermore, we identify knowledge gaps, appraise the available experimental models and propose future directions for the field. The current knowledge and open questions regarding the cardiovascular effects associated with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection are also discussed. This Review is the result of scientific cooperation of members of the Heart Failure Association of the ESC, the Heart Failure Society of America and the Japanese Heart Failure Society.

Comparison of 3D and 2D late gadolinium enhancement magnetic resonance imaging in patients with acute and chronic myocarditis

We compared a fast, single breath-hold three dimensional LGE sequence (3D LGE) with an established two dimensional multi breath-hold sequence (2D LGE) and evaluated image quality and the amount of myocardial fibrosis in patients with acute and chronic myocarditis. 3D LGE and 2D LGE (both spatial resolution 1.5 × 1.5 mm², slice-thickness 8 mm, field of view 350 × 350 mm²) were acquired in 25 patients with acute myocarditis (mean age 40 ± 18 years, 7 female) and 27 patients with chronic myocarditis (mean age 44 ± 22 years, 9 female) on a 1.5 T MR system. Image quality was evaluated by two independent, blinded readers using a 5-point Likert scale. Total myocardial mass, fibrotic mass and total fibrotic tissue percentage were quantified for both sequences in both groups. There was no significant difference in image quality between 3D und 2D acquisitions in patients with acute (p = 0.8) and chronic (p = 0.5) myocarditis. No significant differences between 3D and 2D acquisitions could be shown for myocardial mass (acute p = 0.2; chronic p = 0.3), fibrous tissue mass (acute p = 0.7; chronic p = 0.1) and total fibrous percentage (acute p = 0.4 and chronic p = 0.2). Inter-observer agreement was substantial to almost perfect. Acquisition time was significantly shorter for 3D LGE (24 ± 5 s) as compared to 2D LGE (350 ± 58 s, p < 0.001). In patients with acute and chronic myocarditis 3D LGE imaging shows equal diagnostic quality compared to standard 2D LGE imaging but with significantly reduced acquisition time.

Virome Sequencing in Patients With Myocarditis

BACKGROUND

Polymerase chain reaction analyses of cardiac tissues have detected viral sequences in up to 67% of cases of myocarditis. However, viruses have not been implicated in giant cell myocarditis (GCM). Furthermore, efforts to detect viruses implicated in myocarditis have been unsuccessful in more accessible samples such as peripheral blood.

METHODS

We used Virome Capture Sequencing for Vertbrate Viruses (VirCapSeq-VERT), a method that simultaneously screens for all known vertebrate viruses, to investigate viruses in 33 patients with myocarditis. We investigated peripheral blood mononuclear cells (n=24), plasma (n=27), endomyocardial biopsies (n=2), and cardiac tissue samples from explanted hearts (n=13).

RESULTS

Nine patients (27%) had GCM and 4 patients (13%) had fulminant myocarditis. We found the following viruses in the blood of patients with myocarditis: Epstein Barr virus (n=11, 41%), human pegivirus (n=1, 4%), human endogenous retrovirus K (n=27, 100%), and anellovirus (n=15, 56%). All tissue samples from fulminant myocarditis (n=2) and GCM (n=13) contained human endogenous retrovirus K.

CONCLUSIONS

No nucleic acids from viruses previously implicated in myocarditis or other human illnesses were detected in relevant amounts in cardiac tissue samples from GCM or in blood samples from other types of myocarditis. These findings do not exclude a role for viral infection in GCM but do suggest that if viruses are implicated, the mechanism is likely to be indirect rather than due to cytotoxic infection of myocardium.

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.

Myocarditis presenting as typical acute myocardial infarction: A case report and review of the literature

BACKGROUND

Myocarditis refers to a variety of myocardial inflammatory lesions. A variety of factors such as infection and physical and chemical factors can cause myocarditis. Depending on the severity of myocardial damage, myocarditis patients can manifest heart failure, cardiogenic shock, and even sudden death. Here we present a case of viral myocarditis that mimicked acute coronary syndrome.

CASE SUMMARY

A middle-aged male patient presented with chest pain and elevated troponin I after a flu-like infection. This patient had a history of hypertension and a habit of alcohol and tobacco use. Electrocardiography showed typical changes in acute myocardial infarction, with the T-wave increasing. Coronary angiogram revealed no stenosis. Cardiac magnetic resonance imaging revealed edema of the middle and apical septal and apical anterior walls on T2-weighted images and the T1 mapping. Late gadolinium enhancement of the middle and apical septal and apical anterior walls could be found. Rubella virus immunoglobulin G and immunoglobulin M antibodies were abnormally elevated. The patient was given antiviral and antibiotic treatments, and serum biomarkers and electrocardiograph returned to normal after 5 d of treatment. After one-year follow-up, the patient showed no symptoms, and cardiac magnetic resonance showed that myocardial thickness was significantly thinner than before, and fibrosis was less than before.

CONCLUSION

This case illustrates the utility of cardiac magnetic resonance for diagnosis of infarction-like myocarditis when the angiogram is normal.

Recognition and Initial Management of Fulminant Myocarditis: A Scientific Statement From the American Heart Association

Fulminant myocarditis (FM) is an uncommon syndrome characterized by sudden and severe diffuse cardiac inflammation often leading to death resulting from cardiogenic shock, ventricular arrhythmias, or multiorgan system failure. Historically, FM was almost exclusively diagnosed at autopsy. By definition, all patients with FM will need some form of inotropic or mechanical circulatory support to maintain end-organ perfusion until transplantation or recovery. Specific subtypes of FM may respond to immunomodulatory therapy in addition to guideline-directed medical care. Despite the increasing availability of circulatory support, orthotopic heart transplantation, and disease-specific treatments, patients with FM experience significant morbidity and mortality as a result of a delay in diagnosis and initiation of circulatory support and lack of appropriately trained specialists to manage the condition. This scientific statement outlines the resources necessary to manage the spectrum of FM, including extracorporeal life support, percutaneous and durable ventricular assist devices, transplantation capabilities, and specialists in advanced heart failure, cardiothoracic surgery, cardiac pathology, immunology, and infectious disease. Education of frontline providers who are most likely to encounter FM first is essential to increase timely access to appropriately resourced facilities, to prevent multiorgan system failure, and to tailor disease-specific therapy as early as possible in the disease process.

Radiomics for Distinguishing Myocardial Infarction from Myocarditis at Late Gadolinium Enhancement at MRI: Comparison with Subjective Visual Analysis

Purpose

To evaluate whether radiomics features of late gadolinium enhancement (LGE) regions at cardiac MRI enable distinction between myocardial infarction (MI) and myocarditis and to compare radiomics with subjective visual analyses by readers with different experience levels.

Materials and Methods

In this retrospective, institutional review board-approved study, consecutive MRI examinations of 111 patients with MI and 62 patients with myocarditis showing LGE were included. By using open-source software, classification performances attained from two-dimensional (2D) and three-dimensional (3D) texture analysis, shape, and first-order descriptors were compared, applying five different machine learning algorithms. A nested, stratified 10-fold cross-validation was performed. Classification performances were compared through Wilcoxon signed-rank tests. Supervised and unsupervised feature selection techniques were tested; the effect of resampling MR images was analyzed. Subjective image analysis was performed on 2D and 3D image sets by two independent, blinded readers with different experience levels.

Results

When trained with recursive feature elimination (RFE), a support vector machine achieved the best results (accuracy: 88%) for 2D features, whereas linear discriminant analysis (LDA) showed the highest accuracy (85%) for 3D features (P <.05). When trained with principal component analysis (PCA), LDA attained the highest accuracy with both 2D (86%) and 3D (89%; P =.4) features. Results found for classifiers trained with spline resampling were less accurate than those achieved with one-dimensional (1D) nearest-neighbor interpolation (P <.05), whereas results for classifiers trained with 1D nearest-neighbor interpolation and without resampling were similar (P =.1). As compared with the radiomics approach, subjective visual analysis performance was lower for the less experienced and higher for the experienced reader for both 2D and 3D data.

Conclusion

Radiomics features of LGE permit the distinction between MI and myocarditis with high accuracy by using either 2D features and RFE or 3D features and PCA.© RSNA, 2019Supplemental material is available for this article.

Clinical Presentation and Laboratory Findings in Men Versus Women with Myocarditis

Objectives: Understanding sex differences in myocarditis is crucial to improve clinical care. We sought to investigate sex differences focusing on clinical presentation and laboratory parameters. Methods: From 2011 to 2018, 77 patients were diagnosed with myocarditis according to European Society of Cardiology (ESC) criteria with available clinical, laboratory, and cardiac magnetic resonance imaging data. First, we investigated sex differences of clinical and laboratory parameters in the entire cohort of 77 patients. Second, we focused on patients with acute myocarditis (n = 51) defined as recent symptom onset (≤10 days). Results: Myocarditis was present in 63 men (82%) and 14 women (18%). While men most frequently presented with chest pain (78%), a considerable amount of women presented with dyspnea as the only symptom (40%). Within the entire cohort, only creatinine kinase (CK) was higher in men versus women (364 ± 286 vs. 147 ± 148 U/L, p = 0.007), while in patients with acute myocarditis both CK and myoglobin (Mb) were higher in men versus women (CK: 327 ± 223 vs. 112 ± 65 U/L, p = 0.004 and Mb: 111 ± 126 vs. 25 ± 29 μg/L, p = 0.04). No sex differences were found for high-sensitivity troponin T, C-reactive protein, and NT-probrain natriuretic peptide. Conclusions: This is the first study reporting sex differences in clinical presentation and routine laboratory parameters in myocarditis. While clinical presentation appeared to be subtle in women with dyspnea being the only presenting symptom of myocarditis in a considerable part, men typically complained of chest pain. Similarly to observations in myocardial infarction, atypical symptoms and underdiagnosis may be a cause for under-representation of women in cohorts of myocarditis.

Myocarditis in Athletes Is a Challenge: Diagnosis, Risk Stratification, and Uncertainties

Presentation of myocarditis in athletes is heterogeneous and establishing the diagnosis is challenging with no current uniform clinical gold standard. The combined information from symptoms, electrocardiography, laboratory testing, echocardiography, cardiac magnetic resonance imaging, and in certain cases endomyocardial biopsy helps to establish the diagnosis. Most patients with myocarditis recover spontaneously; however, athletes may be at higher risk of adverse cardiac events. Based on scarce evidence and mainly autopsy studies and expert's opinions, current recommendations generally advise abstinence from competitive sports ranging from a minimum of 3 to 6 months. However, the dilemma poses that (un)necessary prolonged disqualification of athletes to avoid adverse cardiac events can cause considerable disruption to training schedules and tournament preparation and lead to a decline in performance and ability to compete. Therefore, better risk stratification tools are imperatively needed. Using latest available data, this review contrasts existing recommendations and presents a new proposed diagnostic flowchart putting a greater focus on the use of cardiac magnetic resonance imaging in athletes with suspected myocarditis. This may enable cardiac caregivers to counsel athletes with suspected myocarditis more systematically and furthermore allow for pooling of more unified data. To modify recommendations regarding sports behavior in athletes with myocarditis, evidence, based on large multicenter registries including cardiac magnetic resonance imaging and endomyocardial biopsy, is needed. In the future, physicians might rely on combined novel risk stratification methods, by implementing both noninvasive and invasive tissue characterization methods.

Viral myocarditis: a prime example for endomyocardial biopsy-guided diagnosis and therapy

Purpose of review

Myocarditis is an inflammatory disease of the cardiac muscle mainly caused by viral infection. Due to the diverse clinical presentation of myocarditis, accurate diagnosis demands simultaneous histologic, immunohistochemical and molecular biological workup of endomyocardial biopsies (EMBs) as defined by the position statement of the Working Group on Myocardial and Pericardial Diseases of the European Society of Cardiology on myocarditis.

Recent findings

Endomyocardial biopsy-based analysis of viral transcriptional activity, mRNA expression, epigenetics and region-specific protein expression analysis via imaging mass spectrometry have led to the identification of novel potential diagnostic criteria, markers with prognostic value and therapeutic targets for the treatment of viral myocarditis, opening new avenues for novel therapies, including cell therapies, as well as the use of established treatment options, be it from other indications.

Summary

Under certain clinical scenarios EMB-based analysis is required to come to a tailored individualized therapy that improves symptoms and prognosis of patients with acute and chronic viral-driven cardiac inflammation.

Application value of hypersensitive C-reactive protein, lactic acid and myoglobin in the combined detection of myocarditis

Application value of hypersensitive C-reactive protein (hs-CRP), blood lactic acid (LAC) and myoglobin (Mb) in the combined detection of myocarditis was explored. A total of 107 patients with suspected myocarditis treated in The Second Nanning People's Hospital from January 2015 to December 2017 were retrospectively analyzed, of whom 81 patients diagnosed with myocarditis were enrolled into the research group, and 26 non-myocarditis individuals were enrolled into the control group. Fasting venous blood was drawn from all patients to detect the hs-CRP, LAC and Mb, and their levels were compared and analyzed between the two groups. Moreover, the coincidence rate, sensitivity and specificity of single detection and combined detection by hs-CRP, LAC and Mb in the diagnosis of myocarditis were compared and analyzed. There were no significant differences in the sex, age, smoking status, alcohol consumption, chest distress, palpitation, angina and dyspnea between the two groups (P>0.05), proving that patients in both groups were comparable. The levels of hs-CRP, LAC and Mb in the research group were significantly higher than those in the control group, displaying statistically significant differences (P<0.05). According to the receiver operating characteristic (ROC) curve, the area under the curve (AUC), coincidence rate, sensitivity and specificity in the diagnosis of myocarditis, respectively, were 0.610 (95% CI: 0.495–0.725), 58.88, 51.85 and 80.77% for hs-CRP, 0.657 (95% CI: 0.551–0.763), 58.88, 54.32 and 73.08% for LAC, 0.747 (95% CI: 0.651–0.843), 69.16, 64.20 and 84.62% for Mb, and 0.773 (95% CI: 0.680–0.867), 76.64, 79.01 and 69.23% for combined detection. Hs-CRP, LAC and Mb are highly expressed in the serum of patients with myocarditis, and their combined detection has guiding significance for the prevention and treatment of myocarditis.

Non-steroidal anti-inflammatory drug use in acute myopericarditis: 12-month clinical follow-up

Objective

Clinical data on the effect of non-steroidal anti-inflammatory drugs (NSAIDs) in myopericarditis are limited. Since NSAIDs are standard therapy in pericarditis, we retrospectively investigated their safety in myopericarditis.

Methods

In a retrospective case-control study, we identified 60 patients with myopericarditis from September 2010 to August 2017. Diagnosis was based on clinical criteria, elevated high-sensitivity troponin T and cardiac magnetic resonance imaging (CMR). All patients received standard heart failure therapy if indicated. Twenty-nine patients (62%) received NSAIDs (acetylsalicylic acid: n=7, average daily dose =1300 mg or ibuprofen: n=22, average daily dose =1500 mg) for an average duration of 4 weeks. To create two cohorts with similar baseline conditions, 15 patients were excluded. Three months after diagnosis, 29 patients were re-evaluated by CMR to measure late gadolinium enhancement (LGE).

Results

Baseline characteristics of those treated with or without NSAIDs were similar. Mean age was 34 (±13) years, 6 (13%) were women. Mean left ventricular ejection fraction (LVEF) was 56% (±5). 82 % of the patients (14 of 17) treated with NSAIDs experienced a decrease in LGE at 3 months, while it was only 58 % (7 of 12) of those without NSAIDs (p=0.15). At 12-month follow-up, one of the patients treated without NSAIDs experienced polymorphic ventricular tachycardia (VT) with cardiac arrest, while one of the patients with NSAIDs experienced non-sustained VT.

Conclusions

This is the first case-control study demonstrating that NSAIDs are safe in patients with myopericarditis and preserved LVEF. Our data suggest that this drug class should be tested prospectively in a large randomised clinical trial.