Fulminant myocarditis: a comprehensive review from etiology to treatments and outcomes

Clinical analysis of temporary pacemaker implantation in 6 children with fulminant myocarditis

BACKGROUND

There is little literature on the use of temporary pacemakers in children with fulminant myocarditis. Therefore, we summarized the use of temporary cardiac pacemakers in children with fulminant myocarditis in our hospital.

METHODS

The clinical data of children with fulminant myocarditis treated with temporary pacemakers in Wuhan Children's Hospital from January 2017 to May 2022 were retrospectively analyzed.

RESULTS

A total of 6 children were enrolled in the study, including 4 boys and 2 girls, with a median age of 50 months and a median weight of 15 kg. The average time from admission to pacemaker placement was 2.75 ± 0.4 h. The electrocardiogram showed that all 6 children had third-degree atrioventricular block (III°AVB). The initial pacing voltage, the sensory sensitivity of the ventricle and the pacing frequency were set to 5-10 mV, 5 V and 100-120 bpm respectively. The sinus rhythm was recovered in 5 patients within 61 h (17-134) h, and the median time of using temporary pacemaker was 132 h (63-445) h. One of the children had persistent III°AVB after the temporary pacemaker. With parental consent, the child was fitted with a permanent pacemaker on the 12th day of his illness.

CONCLUSIONS

When fulminant myocarditis leads to severe bradycardia or atrioventricular block in children, temporary pacemakers have the characteristics of high safety to improve the heart function.

Cardiac magnetic resonance imaging (MRI) for detecting acute myocardial injury of fulminant myocarditis survivors after extracorporeal membrane oxygenation (ECMO) treatment in adults

AIMS

To detect the acute myocardial injury in fulminant myocarditis (FM) survivors after extracorporeal membrane oxygenation (ECMO) and to demonstrate its significant differences from non-FM patients by cardiac magnetic resonance (CMR).

MATERIALS AND METHODS

This retrospective study enrolled 59 patients with acute myocarditis (AM), including 35 non-FM patients, 24 FM patients, and 54 controls. The peak value of cardiac troponin T (cTnT) was recorded. Tissue parameters, including native T1, extracellular volume (ECV), late gadolinium-enhancement (LGE)%, and T2 by CMR were assessed.

RESULTS

The mean age was 35 ± 14 years, and 45.8% of the population were males in the AM group. Patients had higher levels of peak cTnT, peak NT-proBNP and peak C-reactive protein in the FM group (all p<0.05). Comparing with non-FM, the values of T1-based imaging parameters were significantly higher in the FM group (all p<0.05). In contrast, no difference was observed among the two groups in terms of T2 value (p=0.707). The septal area was more frequently involved in FM survivors after ECMO treatment, both in T1 and T2-based images. In addition, the cubic relationship was the relative best fit of LGE% against logcTnT and indicated that cTnT value exceeding 300ng/L exhibited a rapid upward trend of LGE%.

CONCLUSION

Comparing to non-FM, higher myocardial necrosis and fibrosis but similar edema determined by T1 and T2 based imaging was found in FM survivors after ECMO treatment. Furthermore, the inter-ventricular septal area was more frequently involved by acute myocardial injury in FM survivors after ECMO treatment. In addition, LGE% showed an overall increasing trend with cTnT values elevating with rapidly increasing with cTnT exceeding 300 ng/L.

Chinese Society of Cardiology guidelines on the diagnosis and treatment of adult fulminant myocarditis

Fulminant myocarditis is an acute diffuse inflammatory disease of myocardium. It is characterized by acute onset, rapid progress and high risk of death. Its pathogenesis involves excessive immune activation of the innate immune system and formation of inflammatory storm. According to China's practical experience, the adoption of the "life support-based comprehensive treatment regimen" (with mechanical circulation support and immunomodulation therapy as the core) can significantly improve the survival rate and long-term prognosis. Special emphasis is placed on very early identification,very early diagnosis,very early prediction and very early treatment.

Multisystemic Inflammation Influences Prognosis in Fulminant Lymphocytic Myocarditis

BACKGROUND

Multisystem inflammatory syndrome (MIS) is a hyperinflammatory shock associated with cardiac dysfunction and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. However, there are no reports on using MIS criteria, such as multisystemic inflammation (MSI) in fulminant myocarditis, without SARS-CoV-2 infection. This study investigated the differences in clinical characteristics and course between patients with fulminant lymphocytic myocarditis (FLM) plus MSI and those without MSI.Methods and Results: This multicenter retrospective cohort study included 273 patients with FLM registered in the JROAD-DPC database between April 2014 and March 2017. We evaluated the presence of MSI using criteria modified from previously reported MIS criteria and compared the characteristics and risk of mortality or heart transplantation between FLM patients with MSI and without MSI. Of the 273 patients with FLM, 107 (39%) were diagnosed with MSI. The MSI group was younger (44 vs. 57 years; P<0.0001) and had more females (50% vs. 36%; P=0.0236), a higher incidence of pericardial effusion (58% vs. 40%; P=0.0073), and a lower 90-day mortality rate (19% vs. 33%; P=0.0185) than the non-MSI group. The risk of mortality at 90 days was lower in FLM patients aged <50 years with MSI aged <50 years than in those without MSI (P=0.0463).

CONCLUSIONS

These results suggest that MSI may influence the prognosis of FLM, especially in patients aged <50 years.

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.

Impella device in fulminant myocarditis: Japanese Registry for Percutaneous Ventricular Assist Device (J-PVAD) registry analysis on outcomes and adverse events

AIMS

Given that fulminant myocarditis, characterized by unstable haemodynamics, is a significant clinical challenge and that traditional pharmacological treatments have limitations, evaluating alternatives such as the Impella device is a crucial focus of this study. Further, this study presents pioneering large-scale registry data on its use in managing fulminant myocarditis.

METHODS AND RESULTS

Data from the Japanese Registry for Percutaneous Ventricular Assist Devices (J-PVAD) were analysed to assess Impella's role in managing fulminant myocarditis from February 2020 to December 2021. The primary outcome was 30-day mortality for those treated with Impella. Of the 269 patients treated with Impella, 107 used Impella standalone, and 162 used ECPELLA (Impella combined with extracorporeal membrane oxygenation). The average age was 54 years, with 42.8% females. Overall, 74.3% survived at 30 days. Specifically, the success rate was 68.5% for the ECPELLA group and 83.2% for the Impella standalone group. Cox regression highlighted that lower estimated glomerular filtration rate and pre-Impella systolic blood pressure increased adverse event risk, while Swan-Ganz catheterization use reduced it. Adverse events were noted in 48.7% of patients, such as bleeding (32.0%) and deteriorating renal function (8.6%).

CONCLUSION

Impella's use in fulminant myocarditis demonstrates encouraging short-term outcomes, albeit with significant adverse events. These findings align with previous mechanical circulatory support studies, emphasizing caution regarding haemorrhagic issues. Further studies are essential to enhance patient selection and treatment approaches.

"Extracorporeal membrane oxygenation outcomes in multisystem inflammatory syndrome of childhood - An extracorporeal life support organization registry study"

Multisystem inflammatory disease in childhood (MIS-C) is a novel pediatric syndrome after a COVID-19 infection that causes systemic injury, with potential life-threatening hemodynamic compromise requiring Extracorporeal Membrane Oxygenation (ECMO) support. We performed an observational retrospective cohort study in children aged 0-18 years with MIS-C and non-MIS-C myocarditis on ECMO between January 2020 and December 2021, using the ELSO Registry database. We aimed to compare the outcomes of both populations and to identify factors for decreased survival in MIS-C patients on ECMO. The Extracorporeal Life Support Organization (ELSO) Registry reported 310 pediatric ECMO patients with MIS-C (56.1%) and non-MIS-C myocarditis (43.9%). No difference was found in survival to hospital discharge between groups (67.2% for MIS-C vs 69.1% for non-MIS-C myocarditis, p 0.725). Multivariable analysis demonstrated that ECPR and co-infection were significantly associated with decreased survival to hospital discharge in MIS-C patients (OR 0.138, p 0.01 and OR 0.44, p 0.02, respectively). Outcomes of children with MIS-C on ECMO support are similar to those of non-MIS-C myocarditis despite higher infectious, multiorgan dysfunction and respiratory complications accompanying COVID-19 infections. The use of ECMO for MIS-C patients seems to be feasible and safe. Prospective studies on the use of ECMO support in MIS-C patients may improve outcomes in this pediatric population.

Adolescent Onset of Acute Heart Failure

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

Investigating the virulence of coxsackievirus B6 strains and antiviral treatments in a neonatal murine model

Coxsackievirus B6 (CVB6), a member of the human enterovirus family, is associated with severe diseases such as myocarditis in children. However, to date, only a limited number of CVB6 strains have been identified, and their characterization in animal models has been lacking. To address this gap, in this study, a neonatal murine model of CVB6 infection was established to compare the replication and virulence of three infectious-clone-derived CVB6 strains in vivo. The results showed that following challenge with a lethal dose of CVB6 strains, the neonatal mice rapidly exhibited a series of clinical signs, such as weight loss, limb paralysis, and death. For the two high-virulence CVB6 strains, histological examination revealed myocyte necrosis in skeletal and cardiac muscle, and immunohistochemistry confirmed the expression of CVB6 viral protein in these tissues. Real-time PCR assay also revealed higher viral loads in the skeletal and cardiac muscle than in other tissues at different time points post infection. Furthermore, the protective effect of passive immunization with antisera and a neutralizing monoclonal antibody against CVB6 infection was evaluated in the neonatal mouse model. This study should provide insights into the pathogenesis of CVB6 and facilitate further research in the development of vaccines and antivirals against CVBs.

Cardiogenic Shock in Non-Ischemic Cardiomyopathy: Dynamic Mechanical Circulatory Support and Pathophysiology Illustration

Nonischemic cardiomyopathy (NICM) is a significant cause of cardiogenic shock (CS). We present a case of a 56-year-old previously healthy man who arrived with vague abdominal symptoms, over 2 weeks. Subsequently, the patient's condition rapidly deteriorated over 12 hours, leading to cardiogenic shock categorized as Society for Cardiovascular Angiography and Interventions (SCAI) stage D. Echocardiography and right heart catheterization confirmed multiorgan failure secondary to severe cardiac dysfunction. Mechanical circulatory support was initiated using an Impella CP device 20 hours after admission due to ongoing deterioration. Considering refractory cardiogenic shock and within 24 hours, the patient received combined veno-arterial extracorporeal membrane oxygenation (VA-ECMO) and Impella CP support (ECPElla). With gradual improvement in the patient's clinical status and organ function, successful weaning from VA ECMO to Impella 5.5 was achieved. Ultimately, the patient underwent a successful orthotopic heart and kidney transplantation, marking a significant milestone in his recovery. The case underscores the importance of promptly identifying and responding to cardiogenic shock through invasive hemodynamic assessment. Collaborative decision-making involving a multidisciplinary team played a crucial role in the initiation, escalation, and eventual weaning of mechanical circulatory support, culminating in the successful bridging to a dual organ transplantation for this patient with CS secondary to NICM.

Identification and functional analysis of circulating small extracellular vesicle lncRNA signatures in children with fulminant myocarditis

Fulminant myocarditis (FM) is the most serious type of myocarditis. However, the molecular mechanism underlying the pathogenesis of FM has not been fully elucidated. Small extracellular vesicles (sEVs) play important roles in many diseases, but any potential role in paediatric FM has not been reported. Here, the differential signatures of lncRNAs in plasma sEVs were studied in FM children and healthy children using transcriptome sequencing followed by functional analysis. Then immune-related lncRNAs were screened to study their role in immune mechanisms, the levels and clinical relevance of core immune-related lncRNAs were verified by qRT-PCR in a large sample size. Sixty-eight lncRNAs had increased levels of plasma sEVs in children with FM and 11 had decreased levels. Functional analysis showed that the sEVs-lncRNAs with different levels were mainly related to immunity, apoptosis and protein efflux. Seventeen core immune-related sEVs-lncRNAs were screened, functional enrichment analysis showed that these lncRNAs were closely related to immune activation, immune cell migration and cytokine pathway signal transduction. The results of the study show that sEVs-lncRNAs may play an important role in the pathogenesis of fulminant myocarditis in children, especially in the mechanism of immune regulation.

Transcriptional and functional analysis of plasma exosomal microRNAs in acute viral myocarditis

AIM

To assess the differential expression profiles of exosome-derived microRNA (miRNA) and reveal their potential functions in patients with acute viral myocarditis (AVMC).

MATERIALS & METHODS

Peripheral blood samples were collected from 9 patients diagnosed with AVMC and 9 healthy controls (HC) in the Affiliated Hospital of Qingdao University from July 2021 to September 2022. The exosomal miRNA expression were tested using RNA high-throughput sequencing. We conducted the GO and KEGG functional analysis to predict the potential molecular, biological functions and related signaling pathways of miRNAs in exosomes. Target genes of exosomal miRNAs were predicted and miRNA-target gene network was mapped using gene databases. Differentially expressed exosomal miRNAs were selected and their expression levels were detected by quantitative real-time polymerase chain reaction (qRT-PCR) to verify the sequencing results.

RESULTS

P < 0.05 and Fold Change>2 were considered as cut-off value to screen miRNAs that were differently expressed. This study identified 14 upregulated and 14 downregulated exosome-derived miRNAs. GO and KEGG analysis showed that differentially expressed miRNAs may be related to β-catenin binding, DNA transcription activities, ubiquitin ligase, PI3K-Akt, FoxO, P53, MAPK, and etc.. The target genes of differentially expressed miRNAs were predicted using gene databases. Real-time PCR confirmed the upregulation of hsa-miR-548a-3p and downregulation of hsa-miR-500b-5p in AVMC.

CONCLUSIONS

Hsa-miR-548a-3p and hsa-miR-500b-5p could serve as a promising biomarker of AVMC. Exosomal miRNAs may have substantial roles in the mechanisms of AVMC.

A case report of giant cell myocarditis complicated by severe heart failure: the value of early endomyocardial biopsy and mechanical circulatory support

Background

Giant cell myocarditis (GCM) is a rare, probably underdiagnosed and potentially fatal disease in young and middle-aged patients. Disease progression is often rapid, and life-threatening arrhythmias and cardiogenic shock due to progressive left ventricular failure are among the most feared complications. Although cardiac biomarkers and multimodality imaging are used as initial diagnostic tests in most patients, endomyocardial biopsy (EMB) is often required for a definitive diagnosis. However, there are still gaps in our knowledge in terms of the etiology, early diagnosis, management and prognosis of GCM.

Case Description

We present the case of a male patient in his early 50s admitted to Haukeland University Hospital with fulminant GCM. He had no significant medical history in the past apart from hypertension, and presented to hospital in cardiogenic shock after a few weeks of progressive shortness of breath. Rapid initiation of methylprednisolone had an immediate effect on reducing myocardial inflammation, and sustained treatment with a combination of immunosuppressive agents along with optimal heart failure medications led to complete recovery of the heart function and clinical remission over several years. The case study highlights the urgency of an early EMB, access to mechanical circulatory support (MCS) and the efficacy of immunosuppressive treatment and optimal medical management for heart failure. Finally, our review of the literature also provides an updated guidance on the contemporary management of GCM patients.

Conclusions

Accurate and early diagnosis with EMB in patients with GCM are crucial for better outcomes. Rapid initiation of methylprednisolone reduces myocardial inflammation and the risk of death. Sustained treatment with a combination of immunosuppressive agents together with optimal heart failure medications are essential for myocardial recovery and long-term stabilization. The use of MCS is the cornerstone in the management of GCM with a clear survival benefit.

Advances in research on molecular markers in immune checkpoint inhibitor-associated myocarditis

Immune checkpoint inhibitors (ICIs) play a crucial role in the immunotherapy of malignant tumors, preventing immune evasion by tumor cells and activating autoimmune cells to eliminate the tumor. Despite their proven effectiveness in antitumor therapy, potential immune-related adverse effects must be recognized, particularly ICI-associated myocarditis (ICIAM). ICIAM is the most lethal form of organ immunotoxicity, with a significant impact on short-term mortality. However, ICIAM is predominantly asymptomatic or mildly nonspecific. It is difficult to diagnose, especially due to the lack of unique molecular markers. This article aims to provide a comprehensive overview of the progress made in identifying molecular markers for ICIAM.

Acute heart failure: mechanisms and pre-clinical models-a Scientific Statement of the ESC Working Group on Myocardial Function

While chronic heart failure (CHF) treatment has considerably improved patient prognosis and survival, the therapeutic management of acute heart failure (AHF) has remained virtually unchanged in the last decades. This is partly due to the scarcity of pre-clinical models for the pathophysiological assessment and, consequently, the limited knowledge of molecular mechanisms involved in the different AHF phenotypes. This scientific statement outlines the different trajectories from acute to CHF originating from the interaction between aetiology, genetic and environmental factors, and comorbidities. Furthermore, we discuss the potential molecular targets capable of unveiling new therapeutic perspectives to improve the outcome of the acute phase and counteracting the evolution towards CHF.

Ruxolitinib ameliorated coxsackievirus B3-induced acute viral myocarditis by suppressing the JAK-STAT pathway

BACKGROUND

Accumulating evidences have demonstrated that overwhelming inflammation occurs in the process of Coxsackievirus B3 (CVB3)-induced acute viral myocarditis (AVM). No specific therapy is available. More than an effective Janus-associated kinase (JAK) inhibiter, ruxolitinib exerts a critical role in the inflammatory diseases. In this study, we investigated the potential effect of ruxolitinib on CVB3-induced acute viral myocarditis.

METHOD

In vivo, BALB/c mice were intraperitoneally injected of CVB3, treated of a successive gavage of ruxolitinib for seven days, and subjected to a series of analysis. In vitro, primary bone marrow-derived macrophages (BMDMs) and cardiac fibroblasts were isolated, cultured, treated, harvested and finally detected.

RESULTS

In vivo, acute viral myocarditis was successfully induced by the injection of CVB3 characterized by impaired cardiac function, predominant infiltration of inflammatory cells, necroptosis of myocardium, great increase of cardiac troponin I (cTnI) and cytokine levels, replication of CVB3, and excessive activation of JAK-STAT pathways. Oral administration of ruxolitinib suppressed the activation of JAK-STAT pathway in a dosage-dependent way, lessened the infiltration of inflammatory cells and necroptosis of myocardium, reduced the levels of cTnI and cytokines, and finally alleviated CVB3-induced cardiac dysfunction, with the reduced production of type I interferon and no promising effect on the replication of CVB3. In vitro, the treatment of ruxolitinib inhibited the activation of JAK-STAT pathway and increase of multiple cytokines mRNA levels in BMDMs and had no protective effect against CVB3 replication in cardiac fibroblasts.

CONCLUSIONS

Our study suggested that ruxolitinib ameliorated CVB3-induced AVM by inhibiting the activation of JAK-STAT pathway, infiltration of inflammatory cells and necroptosis of myocardium, which may provide a novel strategy for AVM therapy.

Epoxyeicosatrienoic Acids Prevent Cardiac Dysfunction in Viral Myocarditis via Interferon Type I Signaling

Myocarditis is a challenging inflammatory disease of the heart, and better understanding of its pathogenesis is needed to develop specific drug therapies. Epoxyeicosatrienoic acids (EETs), active molecules synthesized by CYP (cytochrome P450) enzymes from arachidonic acids and hydrolyzed to less active dihydroxyeicosatrienoic acids by sEH (soluble epoxide hydrolase), have been attributed anti-inflammatory activity. Here, we investigated whether EETs have immunomodulatory activity and exert protective effects on coxsackie B3 virus-induced myocarditis. Viral infection altered eicosanoid epoxide and diol levels in both patients with myocarditis and in the murine heart and correlated with the increased expression and activity of sEH after coxsackie B3 virus infection. Administration of a sEH inhibitor prevented coxsackie B3 virus-induced cardiac dysfunction and inflammatory infiltration. Importantly, EET/sEH inhibitor treatment attenuated viral infection or improved viral resistance by activating type I IFN (interferon) signaling. At the molecular level, EETs enhanced the interaction between GSK3β (glycogen synthase kinase-3 beta) and TBK1 (TANK-binding kinase 1) to promote IFN-β production. Our findings revealed that EETs and sEH inhibitors prevent the progress of coxsackie B3 virus-induced myocarditis, particularly by promoting viral resistance by increasing IFN production.

The Balance of CD8-Positive T Cells and PD-L1 Expression in the Myocardium Predicts Prognosis in Lymphocytic Fulminant Myocarditis

INTRODUCTION

The clinical significance and prognostic value of T cell involvement and programmed cell death-1 (PD-1)/programmed cell death ligand-1 (PD-L1) have not been established in lymphocytic fulminant myocarditis (FM). We investigated the prognostic impact of the number of CD4+, CD8+, FoxP3+, and PD-1+ T cells, as well as PD-L1 expression, in cardiomyocytes in lymphocytic FM.

METHODS

This is a single-center observational cohort study. Myocardial tissue was obtained from 16 consecutive patients at lymphocytic FM onset. The median follow-up was 140 days. Cardiac events were defined as a composite of cardiac death and left ventricular-assist device implantation. CD4, CD8, FoxP3, PD-1, and PD-L1 immunostaining were performed on myocardial specimens.

RESULTS

The median age of the patients was 52 years (seven men and nine women). There was no significant difference in the number of CD4+ cells. The number of CD8+ cells and the CD8+/CD4+ T cell ratio were higher in the cardiac event group (Event+) than in the group without cardiac events (Event-) (p = 0.048 and p = 0.022, respectively). The number of FoxP3+ T cells was higher in the Event+ group (p = 0.049). Although there was no difference in the number of PD-1+ cells, cardiomyocyte PD-L1 expression was higher in the Event+ group (p = 0.112). Event-free survival was worse in the group with a high CD8+ cell count (p = 0.012) and high PD-L1 expression (p = 0.049). When divided into three groups based on the number of CD8+ cells and PD-L1 expression (CD8highPD-L1high [n = 8], CD8lowPD-L1high [n = 1], and CD8lowPD-L1low [n = 7]), the CD8highPD-L1high group demonstrated the worst event-free survival, while the CD8lowPD-L1high group had a favorable prognosis without cardiac events (p = 0.041).

CONCLUSION

High myocardial expression of CD8+ T cells and PD-L1 may predict a poor prognosis in lymphocytic FM.

Self-recruited neutrophils trigger over-activated innate immune response and phenotypic change of cardiomyocytes in fulminant viral myocarditis

Fulminant myocarditis (FM) is a life-threatening inflammatory disease. However, the mechanisms underlying its acute onset are unknown. By dynamic cardiac function measurement, we discovered that the initiation of sudden hemodynamic collapse was on day 4 in the mouse model of FM. Single-cell RNA-sequencing study revealed that healthy cardiomyocytes (CMs) lost their contractile and metabolic function and differentiated into pro-angiogenic and pro-inflammatory CMs. Meanwhile, neutrophils, the most expanded immune cells, exhibited a unique developmental trajectory only after migrating to the heart, where they continuously attracted peripheral neutrophils via Cxcl2/Cxcl3, resulting in the acute accumulation of neutrophils in the heart. Well-differentiated cardiac-infiltrating neutrophils, rather than viruses, induced phenotypic changes in CMs. Moreover, neutrophils could amplify cytokine storm by recruiting and activating pro-inflammatory monocytes. Blockade of the self-recruiting loop of neutrophils by targeting the Cxcl2/Cxcl3-Cxcr2 axis substantially alleviated FM in mice. Collectively, we provide a comprehensive single-cell atlas of immune cells and CMs in FM, elucidate the disease pathogenesis, and suggest potential therapeutic strategies.

Sintilimab-Induced Myocarditis in a Patient with Gastric Cancer: A Case Report and Literature Review

Immune checkpoint inhibitors (ICIs) have emerged as a powerful and efficacious therapeutic approach for many cancer patients. Sintilimab is a fully human IgG4 monoclonal antibody that binds with programmed cell death receptor-1 (PD-1) to block its interaction with ligands, thereby enhancing the antitumor effects of T cells. However, ICIs may induce immune-related adverse events (irAEs) in various systems and organs, with fulminant myocarditis being the most severe one. We report the case of a 45-year-old female with gastric cancer who developed chest pain two weeks after chemotherapy with sintilimab; she was diagnosed with immune-associated fulminant myocarditis and experienced an Adams-Stokes syndrome attack in the hospital. Eventually, she was discharged after being treated with methylprednisolone, immunoglobulin, and an IABP.

Development and Validation of a Prediction Model on Adult Emergency Department Patients for Early Identification of Fulminant Myocarditis

OBJECTIVE

It is difficult to predict fulminant myocarditis at an early stage in the emergency department. The objective of this study was to construct and validate a simple prediction model for the early identification of fulminant myocarditis.

METHODS

A total of 61 patients with fulminant myocarditis and 160 patients with acute myocarditis were enrolled in the training and internal validation cohorts. LASSO regression and multivariate logistic regression were selected to develop the prediction model. The selection of the model was based on overall performance and simplicity. A nomogram based on the optimal model was built, and its clinical usefulness was evaluated by decision curve analysis. The predictive model was further validated in an external validation group.

RESULTS

The resulting prediction model was based on 4 factors: systolic blood pressure, troponin I, left ventricular ejection fraction, and ventricular wall motion abnormality. The Brier scores of the final model were 0.078 in the training data set and 0.061 in the internal testing data set, respectively. The C-indexes of the training data set and the testing data set were 0.952 and 0.968, respectively. Decision curve analysis showed that the nomogram model developed based on the 4 predictors above had a positive net benefit for predicting probability thresholds. In the external validation cohort, the model also showed good performance (Brier score=0.007, and C-index=0.989).

CONCLUSION

We developed and validated an early prediction model consisting of 4 clinical factors (systolic blood pressure, troponin I, left ventricular ejection fraction, and ventricular wall motion abnormality) to identify potential fulminant myocarditis patients in the emergency department.

Pediatric Rheumatic Fever With Acute Fulminant Carditis: A Case Report

Acute rheumatic fever (ARF) is a multi-system inflammatory autoimmune disease. It is a significant cause of heart disease and early death worldwide, especially in children in developing countries. We present a case of acute fulminant rheumatic carditis in a child with no obvious predisposing factors, who resided in a developed country where this disease is not endemic. After pathological examination, a diagnosis of ARF with pancarditis was confirmed. This disease was not suspected before the pathological examination because of its low prevalence in Belgium.

Immunopathogenesis and immunomodulatory therapy for myocarditis

Myocarditis is an inflammatory cardiac disease characterized by the destruction of myocardial cells, infiltration of interstitial inflammatory cells, and fibrosis, and is becoming a major public health concern. The aetiology of myocarditis continues to broaden as new pathogens and drugs emerge. The relationship between immune checkpoint inhibitors, severe acute respiratory syndrome coronavirus 2, vaccines against coronavirus disease-2019, and myocarditis has attracted increased attention. Immunopathological processes play an important role in the different phases of myocarditis, affecting disease occurrence, development, and prognosis. Excessive immune activation can induce severe myocardial injury and lead to fulminant myocarditis, whereas chronic inflammation can lead to cardiac remodelling and inflammatory dilated cardiomyopathy. The use of immunosuppressive treatments, particularly cytotoxic agents, for myocarditis, remains controversial. While reasonable and effective immunomodulatory therapy is the general trend. This review focuses on the current understanding of the aetiology and immunopathogenesis of myocarditis and offers new perspectives on immunomodulatory therapies.

Soluble suppression of tumorigenicity 2 associated with fulminant myocarditis in children: A retrospective observational study

Fulminant myocarditis (FM) is associated with high mortality, and studies on soluble suppression of tumorigenicity 2 (sST2) and myocarditis are still scarce. The aim of this study was to investigate the relationship between sST2 and FM in children with myocarditis. This was a single-center retrospective clinical observational study. We continuously included patients diagnosed as suspected viral myocarditis from December 2019 to December 2022. A total of 203 patients younger than 11 years old were enrolled in this study, 22 of whom were diagnosed with FM. The level of sST2 was positively correlated with N-terminal B-type natriuretic peptide (NT-proBNP) (R = 0.5588, P < .0001). After including multiple factors, creatinine (odd ratio [OR] 0.911; 95% confidence interval [CI], 0.842-0.986; P = .021), NT-proBNP (OR 1.000; 95% CI, 1.000-1.000; P = .01), left ventricular ejection fraction (OR 1.306; 95% CI, 1.153-1.478; P < .001) and sST2 (OR 0.982; 95% CI, 0.965-0.999; P = .038) were still risk factors for FM. The area under curve values were 0.852 for the NT-proBNP, 0.817 for the creatinine, 0.914 for the left ventricular ejection fraction, and 0.865 for the sST2, which showed good sensitivity and specificity for FM. Elevated level of sST2 was associated with fulminant myocarditis. sST2 might be used as a potential biomarker for the diagnosis of fulminant myocarditis.

Characteristics of Electrocardiogram Findings in Fulminant Myocarditis

Fulminant myocarditis (FM) is an acute and severe form of myocarditis with rapid progression and poor clinical outcomes in the absence of acute or chronic coronary artery disease. Electrocardiogram (ECG) abnormalities can provide preliminary clues for diagnosis; however, there is a lack of systemic descriptions on ECG changes in FM populations. Thus, a retrospective analysis of 150 consecutive FM patients and 300 healthy controls was performed to determine the characteristic ECG findings in FM. All patients included had markedly abnormal ECG findings. Specifically, 83 (55.33%) patients had significantly lower voltage with remarkably decreased QRS amplitudes in all leads compared with healthy controls (p < 0.01), and 77 (51.33%) patients had a variety of arrhythmias with lethality ventricular tachycardia/ventricular fibrillation in 21 (14.00%) patients and third-degree atrioventricular block in 21 (14.00%) patients, whereas sinus tachycardia was only found in 43 (28.67%) patients with the median heart rate (HR; 88.00 bpm, IQR: 76.00-113.50) higher than that of controls (73.00 bpm, IQR: 68.00-80.00) (p = 0.000). Conduction and repolarization abnormalities were common in patients. A longer QTc interval (452.00 ms, IQR: 419.00-489.50) and QRS duration (94.00 ms, IQR: 84.00-119.00) were observed in patients compared to controls (QTc interval = 399.00 ms, IQR: 386.00-414.00; QRS duration = 90.00 ms, IQR: 86.00-98.00) (p < 0.05). Additionally, HR > 86.50 bpm, QTc > 431.50 ms, and RV5 + SV1 < 1.715 mV can be used to predict FM. Thus, marked and severe ECG abnormalities provide preliminary clues for the diagnosis of FM.

Wuhan 3 years after the outbreak of the pandemic-cardiological insights and perspectives

In November 2019, Wuhan, a city in Central China, became the center of an outbreak of pneumonia of unknown cause, which was later named "coronavirus disease 2019" (COVID-19). COVID-19 is caused by the novel severe acute respiratory distress syndrome coronavirus 2 (SARS-CoV-2) infection. The emergence of novel SARS-CoV‑2 strains and mutations exerted a serious global public health threat. Although various vaccines have been developed, specific anti-SARS-CoV‑2 drugs are limited. As cardiologists, we believe that because SARS-CoV‑2 can bind to the angiotensin 2 receptor on the surface of cardiomyocytes, it may also lead to cardiac injury. COVID-19-associated cardiac injury is not rare in clinical practice, and most of these cases are mild, while a few might progress to fulminant myocarditis (FM). Overactivated immune response and inflammatory storm represent the core pathogenesis of COVID-19-associated FM. Early identification and diagnosis of COVID-19-associated FM are critical for its treatment. Recently, Wuhan was hit by the Omicron variant again. We proposed managing COVID-19-associated cardiac injury according to the severity, which has had a significant effect on outcome.

Left ventricular function changes and echocardiographic predictors in adult survivors of fulminant myocarditis treated with the Chinese protocol

Disagreement exists regarding the long-term prognosis and recovery of left ventricular (LV) function in patients with fulminant myocarditis (FM). This study reported the outcome and LV ejection fraction (EF) changes in FM treated with Chinese protocol, and assessed whether global longitudinal strain (GLS) by two-dimensional speckle tracking echocardiography (2-D STE) could provide additional information. This retrospective study included 46 FM adult patients who applied timely circulatory support and immunomodulatory therapy with adequate doses of both glucocorticoids and immunoglobulins as core approaches and survived after acute phase. They all presented with acute onset of cardiac symptoms < 2 weeks. LV end-diastolic dimensions, LVEF and GLS at discharge and 2-year were obtained and compared. We then performed linear regression and ROC analysis to determine independent factors to predict normalization of GLS at 2-year. At 2 years, the survival was 100% in our cohort. And the GLS improved modestly (15.40 ± 3.89% vs 17.24 ± 2.89%, P = 0.002). At two years, a proportion of patients whose LV function remained abnormal, being 22% evaluated by EF (< 55%) and higher to 37% by GLS (< 17%). Moreover, GLS at discharge but not at presentation correlated with GLS at 2-year (r = 0.402, P = 0.007). The FM adult treated with Chinese protocol have good survival and modest improvement of LV function during 2-year.

COVID-19 infection with complicated fulminant myocarditis: a case report

Herein, we report the case of a young female patient who suffered from myositis and heart failure due to fulminant myocarditis induced by the 2019 coronavirus disease (COVID-19). After receiving intra-aortic balloon pump (IABP) and immunomodulatory treatment, her vital signs gradually stabilized and the IABP was removed. Cardiac and muscle magnetic resonance imaging confirmed extensive myocardial and skeletal muscle edema. Though it is not uncommon for COVID-19 infection to be complicated by myocarditis and myositis, such serious muscle injury warrants clinical vigilance.

Understanding COVID-19-related myocarditis: pathophysiology, diagnosis, and treatment strategies

Coronavirus disease 2019 (COVID-19) disease has infected nearly 600 million people, resulting in > 6 million deaths, with many of them dying from cardiovascular diseases. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection is caused by a combination of the virus surface spike protein and the human angiotensin-converting enzyme 2 (ACE2) receptor. In addition to being highly expressed in the lungs, ACE2 is widely distributed in the heart, mainly in myocardial cells and pericytes. Like other types of viruses, SARS-CoV-2 can cause myocarditis after infecting the myocardial tissue, which is attributed to the direct damage of the virus and uncontrolled inflammatory reactions. Patients with chest tightness, palpitation, abnormal electrocardiogram, and cardiac troponin elevation, should be suspected of myocarditis within 1-3 weeks of COVID-19 infection. When the hemodynamics change rapidly, fulminant myocarditis should be suspected. Cardiac ultrasound, myocardial biopsy, cytokine detection, cardiac magnetic resonance imaging, 18F-fluorodeoxyglucose positron emission tomography, and other examination methods can assist in the diagnosis. Although scientists and clinicians have made concerted efforts to seek treatment and prevention measures, there are no clear recommendations for the treatment of COVID-19-related myocarditis. For most cases of common myocarditis, general symptomatic and supportive treatments are used. For COVID-19-related fulminant myocarditis, it is emphasized to achieve "early identification, early diagnosis, early prediction, and early treatment" based on the "life support-based comprehensive treatment regimen." Mechanical circulatory support therapy can rest the heart, which is a cure for symptoms, and immune regulation therapy can control the inflammatory storms which is a cure for the disease. Furthermore, complications of COVID-19-related myocarditis, such as arrhythmia, thrombosis, and infection, should be actively treated. Herein, we summarized the incidence rate, manifestations, and diagnosis of COVID-19-related myocarditis and discussed in detail the treatment of COVID-19-related myocarditis, especially the treatment strategy of fulminant myocarditis.

Positive Predictive Value of ICD-10-CM Codes for Myocarditis in Claims Data: A Multi-Institutional Study in Taiwan

Purpose

The validity of the diagnosis codes to identify myocarditis cases in healthcare databases research remains unclear, and this study aimed to determine the coding accuracy of myocarditis in Taiwan.

Methods

We conducted a cross-sectional study based on Taiwan's largest multi-institutional healthcare system to identify inpatients newly diagnosed with ICD-10-CM myocarditis codes at discharge between January 1st, 2017 and March 31st, 2022. We ascertained the myocarditis diagnosis by a gold standard biopsy or by review of electronic medical records, and the positive predictive values (PPV) with 95% confidence intervals (CI) of the ICD-10-CM codes for myocarditis were determined.

Results

We included a total of 498 inpatients (mean age: 33.8 years old; female: 38.8%) with new myocarditis diagnosis at discharge. Codes I409 (30.1%) and I514 (45.4%) constituted the majority of myocarditis diagnostic codes in any coding position, and the overall PPV of the myocarditis codes was 73.5% (95% CI: 69.6-77.4%). However, the highest PPV (96.6%) for myocarditis diagnosis was noted with code I409 as the primary diagnosis. We found 132 inpatients (26.5%) who were false-positive myocarditis cases, identified by the ICD-10-CM codes, and potential reasons for misclassification included other inflammation diseases (n=35, 26.5%), pre-existing heart failure (n= 25, 18.9%) and acute myocardial infarction (n=16, 12.1%).

Conclusion

The PPV of ICD-10-CM codes for myocarditis in Taiwan was acceptable, but some other inflammation diseases and pre-existing heart diseases may be falsely coded as myocarditis. Our results may serve future secondary database studies as a fundamental reference on the validity of myocarditis diagnosis codes.

Acute myocarditis during adjuvant therapies for breast cancer: a case report

BACKGROUND

With the improvement of optimal perioperative drug therapy for breast cancer patients, physicians now have to treat the adverse effects and comorbidities associated with long-term treatments. We report a case who suffered cardiac arrest due to acute myocarditis developed after initiation of adjuvant treatment.

CASE PRESENTATION

After completing preoperative chemotherapy and undergoing curative surgery for right breast cancer, a 46-year-old female patient started adjuvant tamoxifen and resumed trastuzumab. Two months later, she complained fever and dyspnea. Blood tests showed a marked increase in hepatic enzymes, and the patient was rushed to our emergency room on suspicion of drug-induced liver injury. In the emergency room, the patient went into cardiac arrest shortly after tachycardia with ST-segment elevation appeared on the monitored electrocardiogram. Resuscitation was started immediately and tracheal intubation, intra-aortic balloon pumping, and extracorporeal membrane oxygenation were started. Coronary angiography results were negative for ischemic heart disease. A diagnosis of fulminant myocarditis was made and steroid pulse therapy and immunoglobulin therapy were started. After the start of treatment, the symptoms of heart failure improved steadily and the patient was discharged on the 28th day. Histological findings of the myocardial biopsy revealed degeneration and necrosis of myocardial cells with marked lymphocytic infiltration, consistent with the histology of lymphocytic myocarditis. Serum cytomegalovirus, coxsackie B virus and adenovirus antibodies were all elevated and these findings were consistent with acute viral myocarditis.

CONCLUSIONS

We report a case with strong indications for therapy-induced liver damage, who was ultimately diagnosed with acute viral myocarditis and successfully treated with multidisciplinary therapy. We believe that our findings would be useful for other clinicians in managing similar patients.

Influence of confirmed viral infection on adult acute fulminant myocarditis supported with extracorporeal membrane oxygenation

BACKGROUND

The impact of etiologies of acute fulminant myocarditis (AFM), which requires extracorporeal membrane oxygenation (ECMO), on clinical outcomes remains unknown. This study aimed to investigate the risk factors for ECMO weaning and mortality among patients with AFM due to viral etiologies in a tertiary referral medical center.

METHODS

We included 33 adults with AFM who received ECMO and were admitted between January 2002 and January 2021. General demographics, laboratory data, echocardiography findings, and long-term outcomes were analyzed for confirmed viral etiology and unconfirmed etiology groups.

RESULTS

The overall hospital survival rate was 54.5%. The age, sex, severity of the hemodynamic condition, and cardiac rhythm were similar between the two groups. Multivariate Cox regression analysis revealed that a confirmed viral etiology (HR 4.201, 95% CI 1.061-16.666), peri-ECMO renal replacement therapy (RRT) (HR 9.804, 1.140-83.333) and a high positive end-expiratory pressure (PEEP) in the ventilator settings at 24 h after ECMO (HR 1.479, 1.020-2.143) were significant prognostic factors for in-hospital mortality. Peri-ECMO RRT was also a significant negative prognostic factor for successful ECMO weaning (OR 0.061, 0.006-0.600) in the multivariate logistic model.

CONCLUSIONS

Among AFM patients receiving ECMO support, RRT use was associated with a decreased chance of survival to ECMO weaning. Multiple organ dysfunction and a high PEEP were also predictive of a lower chance of hospital survival. Those with a confirmed diagnosis of viral myocarditis may require more medical attention due to the higher risk of hospital mortality than those without a definite diagnosis.

Possible Long-Term Cardiovascular Effects of COVID-19

Coronavirus Disease 2019 is caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and has become a worldwide pandemic. Since 2019, the virus has mutated into multiple variants that have made it harder to eradicate and have increased the rate of infection. This virus can affect the structure and the function of the heart and can lead to cardiovascular symptoms that can have long-lasting effects despite recovery from COVID-19. These symptoms include chest pain, palpitations, fatigue, shortness of breath, rapid heartbeat, arrhythmias, cough and hypotension. These symptoms may persist due to myocardial injury, cardiac inflammation or systemic damage that may have been caused during infection. If these symptoms persist, the patient should visit their cardiologist for diagnosis and treatment plan for any type of cardiovascular disease that may have developed Post-COVID 19.

Myocarditis in the forensic setting

Diagnosis of myocarditis as the cause of death in the forensic setting at post-mortem is currently determined by a forensic pathologist. There is no systematic method for diagnosis and thus the determination is subject to inter-observer variability and is often non-reproducible. The primary aim of this study was to investigate the differences in the amount of inflammation between cases where myocarditis was deemed the cause of death, compared to cases where myocardial inflammation was incidentally present at autopsy, but not determined to be the cause of death. Participants were sourced from the Victorian Institute of Forensic Medicine (VIFM) database, from full autopsies conducted on reportable death in Victoria, Australia between the years 2011 and 2021. Cases of fatal myocarditis were significantly more likely to experience infection-like symptoms prior to death, and to be in hospital at the time of death. Histopathological examination revealed fatal cases had a significantly higher inflammatory index compared to the incidental group. Lethal cases were also significantly more likely to have myocyte necrosis, and a diffuse pattern of inflammation. There are significant differences between cases where myocardial inflammation has been determined to be the cause of death and cases where inflammation in the myocardium was an incidental finding. These results could be used in the forensic autopsy to help pathologists determine if inflammation should be considered fatal or incidental.

Plasma Siglec-5 and CD163 as Novel Biomarkers for Fulminant Myocarditis

Fulminant myocarditis (FM) is the severest type of myocarditis and requires timely diagnosis and treatment. However, effective biomarkers for early diagnosis of FM are limited. First, 12 common inflammatory cytokines levels in the plasma of patients with FM were measured using human cytokine 12-Plex assay. Then, enzyme-linked immunosorbent assay (ELISA) was used to detect the plasma levels of another eight cytokines that we previously reported on. Moreover, a Spearman correlation test was employed to investigate the correlations between the plasma cytokine levels and the clinical parameters of patients with FM. Finally, receiver operating characteristic (ROC) curve analyses were performed to assess the diagnostic performance of plasma cytokine levels for the detection of FM. Five of the twelve common inflammation cytokines were significantly altered in patients with FM, but none of them was correlated with the severity of FM. Six of the eight significantly changed cytokines that we previously reported on were validated by ELISA. Among these, sST2, Siglec-5, and CD163 were negatively correlated with ejection fraction values. Furthermore, plasma Siglec-5 and CD163 levels were found to be associated with the severity of FM. Finally, both plasma Siglec-5 and CD163 showed outstanding diagnostic performance for FM. The current study identified plasma Siglec-5 and CD163 as valuable novel biomarkers for the early diagnosis of FM.

Acute Perimyocarditis - an ST-Elevation Myocardial Infarction Mimicker: A Case Report

BACKGROUND A normal coronary angiogram in ST-elevation myocardial infarction (STEMI) can be considered a myocardial infarction with non-obstructive coronary arteries (MINOCA) until an alternative diagnosis is obtained. However, the COVID-19 pandemic might delay urgent coronary angiography in a resource-limited setting. Perimyocarditis often causes symptoms, such as chest pain, as well as ST-elevation and high cardiac troponin levels. This STEMI mimicker can also cause cardiogenic shock and death when not treated properly. CASE REPORT A 40-year-old man reported having acute onset of substernal chest pain, which was suspected to be STEMI. The patient was an active smoker without any risk factors or a history of cardiovascular disease. The examination showed elevated cardiac troponin I, ST-elevation in high lateral leads, and regional wall motion abnormality (RWMA) by echocardiogram. Furthermore, thrombolytic therapy had failed, and rescue percutaneous coronary intervention was not performed due to the catheterization laboratory limitation during the COVID-19 pandemic. Before coronary angiography, the patient was scheduled for 2 consecutive days of COVID-19 polymerase chain reaction (PCR) swabs. On the second day of hospitalization, the patient experienced a cardiogenic shock. The COVID-19 PCR results were negative, while coronary angiography revealed normal coronary arteries. The patient was eventually diagnosed with probable acute perimyocarditis. CONCLUSIONS Myocarditis is implicated in young patients without typical cardiovascular risk factors or in those with recent infection and cardiovascular symptoms mimicking acute coronary syndrome. It might also be present in situations where ST-elevation distribution on the electrocardiogram is discordant with the RWMA observed on the echocardiogram.

Multimodality imaging in acute myocarditis

The diagnosis of acute myocarditis often involves several noninvasive techniques that can provide information regarding volumes, ejection fraction, and tissue characterization. In particular, echocardiography is extremely helpful for the evaluation of biventricular volumes, strain and ejection fraction. Cardiac magnetic resonance, beyond biventricular volumes, strain, and ejection fraction allows to characterize myocardial tissue providing information regarding edema, hyperemia, and fibrosis. Contemporary cardiac computed tomography angiography (CCTA) can not only be extremely important for the assessment of coronary arteries, pulmonary arteries and aorta but also tissue characterization using CCTA can be an additional tool that can explain chest pain with a diagnosis of myocarditis.

A case of COVID ‐19‐associated fulminant myocarditis successfully treated with mechanical circulatory support

A 49‐year‐old man, who had not been vaccinated against COVID‐19 visited the hospital for fever and cough, and a PCR test for COVID‐19 was positive on the Day X. Initially, there was no decrease in oxygen saturation and the patient was under observation as a mild case without medication. Five days after the onset (Day X + 5), chest pain appeared. Electrocardiogram showed widespread ST‐segment elevation, and blood tests showed high levels of troponin I. However, given that there was no stenotic lesion on coronary computed tomography, myocarditis was suspected, and he was transferred to our hospital on the Day X + 6. We started treatment with lemdesivir and dexamethasone. On the Day X + 7, the patient developed decreased left ventricular ejection fraction, hypotension, and hyperlactatemia. We decided that mechanical circulatory support was necessary and an Impella 5.0 was inserted under ventilator management. The patient was successfully weaned from the Impella 5.0 on the Day X + 17, was transferred to the general ward on the Day X + 24, continued rehabilitation, and was discharged home on the Day X + 39 with no heart failure symptoms. In this case, we performed daily bedside echocardiography and chose the Impella 5.0 instead of extra corporeal membrane oxygenation (ECMO) because there were no findings of severe pneumonia or right heart failure. The Impella 5.0 device was inserted via an axillary artery approach, given that it provides more assisted flow than the Impella CP inserted through the inguinal route. Furthermore, early rehabilitation was possible due to the lack of restriction of the lower body.

We describe a case of coronavirus disease 2019 (COVID‐19)‐associated fulminant myocarditis that was successfully treated with circulatory support with an Impella 5.0. Choosing an appropriate device, careful and repeated observation of clinical symptoms, especially left and right heart function, is important. Echocardiography was useful for this evaluation.

COVID-19 Vaccine-Induced Myocarditis: A Systemic Review and Literature Search

Myocarditis is one of the complications reported with COVID-19 vaccines, particularly both Pfizer-BioNTech and Moderna vaccines. Most of the published data about this association come from case reports and series. Integrating the geographical data, clinical manifestations, and outcomes is therefore important in patients with myocarditis to better understand the disease. A thorough literature search was conducted in Cochrane library, PubMed, ScienceDirect, and Google Scholar for published literature till 30 March 2022. We identified 26 patients eligible from 29 studies; the data were pooled from these qualifying case reports and case series. Around 94% of patients were male in this study, the median age for onset of myocarditis was 22 years and 85% developed symptoms after the second dose. The median time of admission for patients to hospitals post-vaccination was three days and chest pain was the most common presenting symptom in these patients. Most patients had elevated troponin on admission and about 90% of patients had cardiac magnetic resonance imaging (CMR) that showed late gadolinium enhancement. All patients admitted with myocarditis were discharged home after a median stay of four days. Results from this current analysis show that post-mRNA vaccination myocarditis is mainly seen in young males after the second dose of vaccination. The pathophysiology of vaccine-induced myocarditis is not entirely clear and late gadolinium enhancement is a common finding on CMR in these patients that may indicate myocardial fibrosis or necrosis. Prognosis remains good and all patients recovered from myocarditis, however further studies are advisable to assess long-term prognosis of myocarditis.

Neuraminidase inhibitor treatment is associated with decreased mortality in COVID-19 patients: a retrospective analysis

Aims

The aim of this study was to investigate the effects of Neuraminidase inhibitors (NI) on COVID-19 in a retrospective study.

Methods and results

The study included an overall COVID-19 patients (n = 3267) and a 1:1 propensity score-matched patients (n = 972). The levels of plasma N-acetylneuraminic acid and neuraminidase expression were further evaluated in a panel of hospitalized and 1-month post-infection recovered COVID-19 subjects. The mortality rate in the overall patients was 9.6% (313/3267) and 9.2% (89/972) in the propensity-score matched patients. The NI treatment lowered the mortality rate (5.7% vs. 10.3%) and the critically ill conversion rate (14.1% vs. 19.7%) compare to those in the non-NI group in the overall patients and evaluated in the propensity score-matched patients when applying the multivariate Cox model for adjusting imbalanced confounding factors. Furthermore, NI treatment was associated with attenuated cytokine storm levels and acute heart injury but not liver or kidney injuries. Further analysis in a small panel of patients found the levels of N-acetylneuraminic acid and neuraminidase (dominantly the NEU3 isoform) were elevated in the hospitalized COVID-19 subjects and recovered at the 1-month post-infection stage, suggesting increasing desialylation in COVID-19 patients.

Conclusion

These results suggest that NI treatment is associated with decreased mortality in COVID-19 subjects, especially for those subjects with acute heart injury.

AAV9-mediated functional screening for cardioprotective cytokines in Coxsackievirus-B3-induced myocarditis

Viral myocarditis (VM) is an important cause of heart failure (HF) in children and adults. However, the molecular determinants involved in cardiac inflammation and cardiomyocyte necrosis remain poorly characterized, and cardioprotective molecules are currently missing. Here, we applied an in vivo method based on the functional selection (FunSel) of cardioprotective factors using AAV vectors for the unbiased identification of novel immunomodulatory molecules in a Coxsackievirus B3 (CVB3)-induced myocarditis mouse model. Two consecutive rounds of in vivo FunSel using an expression library of 60 cytokines were sufficient to identify five cardioprotective factors (IL9, IL3, IL4, IL13, IL15). The screening also revealed three cytokines (IL18, IL17b, and CCL11) that were counter-selected and likely to exert a detrimental effect. The pooled overexpression of the five most enriched cytokines using AAV9 vectors decreased inflammation and reduced cardiac dilatation, persisting at 1 month after treatment. Individual overexpression of IL9, the top ranking in our functional selection, markedly reduced cardiac inflammation and injury, concomitant with an increase of anti-inflammatory Th2-cells and a reduction of pro-inflammatory Th17- and Th22-cells at 14 days post-infection. AAV9-mediated FunSel cardiac screening identified IL9 and other four cytokines (IL3, IL4, IL13, and IL15) as cardioprotective factors in CVB3-induced VM in mice.

Pediatric Myocarditis: What Have We Learnt So Far?

Myocarditis is an inflammatory disease of the myocardium that is troublesome to diagnose and manage, especially in children. Since the introduction of endomyocardial biopsy (EMB), new diagnostic tools have provided useful data. Especially when enhanced with immunohistochemistry and polymerase chain reaction (PCR) studies, EMB remains the gold standard for the diagnosis. Notably, cardiac magnetic resonance (MRI) is a non-invasive tool that can confirm the diagnosis and has a particular usefulness during the follow-up. The causes of myocarditis are heterogeneous (mostly viral in children). The course and outcome of the illness in the pediatric population represent a complex interaction between etiologic agents and the immune system, which is still not fully understood. The clinical presentation and course of myocarditis vary widely from paucisymptomatic illness to acute heart failure refractory to therapy, arrhythmias, angina-like presentation and sudden cardiac death. In this setting, cardiac biomarkers (i.e., troponins and BNP), although unspecific, can be used to support the diagnosis. Finally, the efficacy of therapeutic strategies is controversial and not confirmed by clinical trials. In this review, we summarized the milestones in diagnosis and provided an overview of the therapeutic options for myocarditis in children.

Prognosis Implication of N-Terminal Pro-B-Type Natriuretic Peptide in Adult Patients With Acute Myocarditis

Background

The aim of this study is to investigate the role of N-terminal pro-B-type natriuretic peptide (NT-proBNP) in assessing the poor outcomes of adult patients with acute myocarditis.

Methods

A total of 170 adult patients with available NT-proBNP information were included in the study. They were grouped according to quartiles of NT-proBNP concentrations at admission. Baseline and follow-up information was collected. Thirty-day major adverse cardiac events (MACE) were death and heart transplantation. Long-term MACE included all-cause death, heart transplantation, re-hospitalization due to heart failure, sustained ventricular arrhythmia, and myocarditis relapse.

Results

During a median follow-up of 3.8 years, patients in the highest NT-proBNP quartile suffered from the highest risk both of 30-day and long-term MACE (P &lt; 0.001 by log-rank test). Multivariate analysis showed that apart from left ventricular ejection fraction (LVEF), an increased baseline NT-proBNP &gt; 3,549 pg/mL (hazard ratio 3.535, 95% CI 1.316–9.499, P = 0.012) and NT-proBNP &gt; 7,204 pg/mL (hazard ratio 22.261, 95% CI 1.976–250.723, P = 0.012) was independent predictor of long-term and 30-day MACE, respectively.

Conclusions

Higher baseline NT-proBNP level was an independent predictor of poor outcomes in adult patients with acute myocarditis. Therefore, NT-proBNP may serve as a useful biomarker for risk stratification in acute myocarditis patients.

Sex-Specific Cardiovascular Risks of Cancer and Its Therapies

In both cardiovascular disease and cancer, there are established sex-based differences in prevalence and outcomes. Males and females may also differ in terms of risk of cardiotoxicity following cancer therapy, including heart failure, cardiomyopathy, atherosclerosis, thromboembolism, arrhythmias, and myocarditis. Here, we describe sex-based differences in the epidemiology and pathophysiology of cardiotoxicity associated with anthracyclines, hematopoietic stem cell transplant (HCT), hormone therapy and immune therapy. Relative to males, the risk of anthracycline-induced cardiotoxicity is higher in prepubertal females, lower in premenopausal females, and similar in postmenopausal females. For autologous hematopoietic cell transplant, several studies suggest an increased risk of late heart failure in female lymphoma patients, but sex-based differences have not been shown for allogeneic hematopoietic cell transplant. Hormone therapies including GnRH (gonadotropin-releasing hormone) modulators, androgen receptor antagonists, selective estrogen receptor modulators, and aromatase inhibitors are associated with cardiotoxicity, including arrhythmia and venous thromboembolism. However, sex-based differences have not yet been elucidated. Evaluation of sex differences in cardiotoxicity related to immune therapy is limited, in part, due to low participation of females in relevant clinical trials. However, some studies suggest that females are at increased risk of immune checkpoint inhibitor myocarditis, although this has not been consistently demonstrated. For each of the aforementioned cancer therapies, we consider sex-based differences according to cardiotoxicity management. We identify knowledge gaps to guide future mechanistic and prospective clinical studies. Furthering our understanding of sex-based differences in cancer therapy cardiotoxicity can advance the development of targeted preventive and therapeutic cardioprotective strategies.

Full recovery after prolonged resuscitation in a pediatric patient due to fulminant myocarditis: a case report with three-year follow-up

Background

Fulminant myocarditis (FM) is a common life-threatening disease in pediatric patients, which can result in sudden cardiac arrest (CA). Whether prolonged cardiopulmonary resuscitation (CPR) is beneficial to FM induced CA is unknown.

Case presentation

We reported the case of an 8-year-old child with FM. At 14:49 of the day after admission, the ECG monitoring indicated ventricular flutter. The patient was immediately given continuous external cardiac compression. Electric cardioversion (energy 30J) and electric defibrillation (energy 50 J, 100 J, 100 J) were given. Continuous chest compression was conducted until extracorporeal membrane oxygenation (ECMO) successfully placed at 19:30 P.M. The total duration of CPR was 291 min. Nine days later, the ECMO was removed; and 29 days later, the patient was discharged from hospital. In the three years of follow-up, the boy showed a full recovery without neurological sequela. At present, his daily activities have returned to normal and his academic performance at school is excellent.

Conclusions

Prolonged CPR can be used in FM induced in-hospital CA in pediatric patients, especially during preparation for ECMO after the failure of standard resuscitation measures.

Case Report: COVID-19 Vaccination Associated Fulminant Myocarditis

Herein, we describe a novel finding of fulminant myocarditis (FM) in two subjects the day after administration of the first dose of the currently available inactivated SARS-CoV-2 vaccine (Vero cell). Cardiac magnetic resonance imaging revealed extensive myocardial edema and necrosis. A pathologic evaluation of the endocardial biopsy tissues revealed inflammatory cell (lymphocytes) infiltration and interstitial edema, myocyte necrosis, and focal areas of fibrosis. A life-support-based comprehensive treatment regimen comprising mechanical circulatory support using intra-aortic balloon pulsation and immunomodulatory therapy—glucocorticoids and intravenous immunoglobulin—was used to treat the patients with FM; eventually, the patients recovered and were discharged. To our knowledge, these are the first two reported cases of FM, with no other identified cause or associated illness, after receiving the inactivated SARS-CoV-2 vaccine (Vero cell). These findings suggest a novel pathogenesis of myocarditis which mentions to pay more attention to this rare, but lethal complication of COVID-19 vaccination.