Myocarditis

Role of the Lymphatics in Cardiac Disease

Cardiovascular diseases remain the largest cause of death worldwide with recent evidence increasingly attributing the development and progression of these diseases to an exacerbated inflammatory response. As a result, significant research is now focused on modifying the immune environment to prevent the disease progression. This in turn has highlighted the lymphatic system in the pathophysiology of cardiovascular diseases owing, in part, to its established function in immune cell surveillance and trafficking. In this review, we highlight the role of the cardiac lymphatic system and its potential as an immunomodulatory therapeutic target in selected cardiovascular diseases.

Caboxamycin Inhibits Heart Inflammation in a Coxsackievirus B3-Induced Myocarditis Mouse Model

Coxsackievirus B3 (CVB3) is a positive single-strand RNA genome virus which belongs to the enterovirus genus in the picornavirus family, like poliovirus. It is one of the most prevalent pathogens that cause myocarditis and pancreatitis in humans. However, a suitable therapeutic medication and vaccination have yet to be discovered. Caboxamycin, a benzoxazole antibiotic isolated from the culture broth of the marine strain Streptomyces sp., SC0774, showed an antiviral effect in CVB3-infected HeLa cells and a CVB3-induced myocarditis mouse model. Caboxamycin substantially decreased CVB3 VP1 production and cleavage of translation factor eIF4G1 from CVB3 infection. Virus-positive and -negative strand RNA was dramatically reduced by caboxamycin treatment. In addition, the cleavage of the pro-apoptotic molecules BAD, BAX, and caspase3 was significantly inhibited by caboxamycin treatment. In animal experiments, the survival rate of mice was improved following caboxamycin treatment. Moreover, caboxamycin treatment significantly decreased myocardial damage and inflammatory cell infiltration. Our study showed that caboxamycin dramatically suppressed cardiac inflammation and mouse death. This result suggests that caboxamycin may be suitable as a potential antiviral drug for CVB3.

An Update on Myocarditis in Forensic Pathology

In forensic medicine, myocarditis is a complicated topic in the context of sudden death and medical malpractice. A good knowledge of the etiopathology, histopathology, and available literature are both indispensable and essential for the correct management and evaluation of the causal link. Some agents, which are rarely lethal for humans, are not necessarily related to death from myocarditis, even if an infection in other organs such as the gastrointestinal tract is documented. The diagnosis of the causes of death is often difficult and confusing. In some cases, the hypothetical diagnosis of myocarditis as the cause of death is formulated by deduction, causing error and misleading the correct temporal evaluation of pathological events. We reviewed the literature realizing that histomorphological data are scarce and often poorly documented. Only after COVID-19 have the histomorphological aspects of myocarditis been better documented. This is due to poor autopsy practice and poor accuracy in identifying the specific histotype of myocarditis with identification of the responsible agent. We believe that four points are essential for a better understanding and complete diagnosis of the disease: (1) clinical classification of myocarditis; (2) etiological classification of myocarditis; (3) pathophysiology of viral and bacterial infections with host response; and (4) histopathological diagnosis with precise identification of the histotype and pathogen. In the review we provide histological images from authoritative scientific references with the aim of providing useful information and food for thought to readers.

Sex differences in myocarditis hospitalizations: Rates, outcomes, and hospital characteristics in the National Readmission Database

Inflammation of the myocardium, or myocarditis, presents with varied severity, from mild to life-threatening such as cardiogenic shock or ventricular tachycardia storm. Existing data on sex-related differences in its presentation and outcomes are scarce. Using the Nationwide Readmission Database (2016-2019), we identified myocarditis hospitalizations and stratified them according to sex to either males or females. Multivariable regression analyses were used to determine the association between sex and myocarditis outcomes. The primary outcome was in-hospital mortality, and the secondary outcomes included sudden cardiac death (SCD), cardiogenic shock (CS), use of mechanical circulatory support (MCS), and 90-day readmissions. We found a total of 12,997 myocarditis hospitalizations, among which 4,884 (37.6 %) were females. Compared to males, females were older (51 ± 15.6 years vs. 41.9 ± 14.8 in males) and more likely to have connective tissue disease, obesity, and a history of coronary artery disease. No differences were noted between the two groups with regards to in-hospital mortality (adjusted odds ratio [aOR] 1.20; confidence interval [CI] 0.93-1.53; P = 0.16), SCD (aOR:1.18; CI 0.84-1.64; P = 0.34), CS (aOR: 1.01; CI 0.85-1.20;P = 0.87), or use of MCS (aOR: 1.07; CI:0.86-1.34; P = 0.56). In terms of interventional procedures, females had lower rates of coronary angiography (aOR: 0.78; CI 0.70-0.88; P < 0.01), however, similar rates of right heart catheterization (aOR 0.93; CI:0.79-1.09; P = 0.36) and myocardial biopsy (aOR: 1.16; CI:0.83-1.62; P = 0.38) compared to males. Additionally, females had a higher risk of 90-day all-cause readmission (aOR: 1.25; CI: 1.16-1.56; P < 0.01) and myocarditis readmission (aOR:1.58; CI 1.02-2.44; P = 0.04). Specific predictors of readmission included essential hypertension, congestive heart failure, malignancy, and peripheral vascular disease. In conclusion, females admitted with myocarditis tend to have similar in-hospital outcomes with males; however, they are at higher risk of readmission within 90 days from hospitalization. Further studies are needed to identify those at higher risk of readmission.

Cardiovascular diseases crossroads: cGAS-STING signaling and disease progression

It is now widely accepted that inflammation is critical in cardiovascular diseases (CVD). Here, studies are being conducted on how cyclic GMP-AMP synthase (cGAS), a component of innate immunity's DNA-sensing machinery, communicates with the STING receptor, which is involved in activating the immune system's antiviral response. Significantly, a growing body of research in recent years highlights the strong activation of the cGAS-STING signalling pathways in several cardiovascular diseases, such as myocardial infarction, heart failure, and myocarditis. This developing collection of research emphasises these pathways' crucial role in initiating and advancing cardiovascular disease. In this extensive narrative, we explore the role of the cGAS-STING pathway in the development of CVD. We elaborate on the basic mechanisms involved in the onset and progression of CVD. This review explores the most recent developments in the recognition and characterization of cGAS-STING pathway. Additionally, it considers the field's future prospects while examining how cGAS-STING pathway might be altered and its clinical applications for cardiovascular diseases.

M2 macrophage exosome-derived lncRNA AK083884 protects mice from CVB3-induced viral myocarditis through regulating PKM2/HIF-1α axis mediated metabolic reprogramming of macrophages

Viral myocarditis (VM) is a clinically common inflammatory disease. Accumulating literature has indicated that M2 macrophages protect mice from Coxsackievirus B3 (CVB3)-induced VM. However, mechanisms that underlie M2 macrophages alleviating myocardial inflammation remain largely undefined. We found that M2 macrophage-derived exosomes (M2-Exo) can effectively attenuate VM. The long non-coding RNA (lncRNA) AK083884 in M2-Exo was found to be involved in the regulation of macrophage polarization by exosome lncRNA sequencing combined with in vitro functional assays. M2-Exo-derived AK083884 promotes macrophage M2 polarization and protects mice from CVB3-induced VM. Furthermore, we identified pyruvate kinase M2 (PKM2) as a protein target binding to AK083884 and found that PKM2 knockdown could promote macrophages to polarize to M2 phenotype. Intriguingly, functional assay revealed that downregulation of AK083884 promotes metabolic reprogramming in macrophages. In addition, co-immunoprecipitation was performed to reveal AK083884 could interact with PKM2 and inhibition of AK083884 can facilitate the binding of PKM2 and HIF-1α. Collectively, our findings uncovered an important role of M2-Exo-derived AK083884 in the regulation of macrophage polarization through metabolic reprogramming, identified a new participant in the development of VM and provided a potential clinically important therapeutic target.

Therapeutic Apheresis and Nephrologist: New and old aspects

The clinical efficacy of therapeutic apheresis is still controversial. We undertook a retrospective review of apheresis treatment to ascertain its safety and efficacy. The therapeutic apheresis consists of a continuously improving therapeutic method for diseases with high mortality and morbidity, especially in cases with poor outcome by using current medications.

Myocardial Oedema as a Consequence of Viral Infection and Persistence-A Narrative Review with Focus on COVID-19 and Post COVID Sequelae

Microvascular integrity is a critical factor in myocardial fluid homeostasis. The subtle equilibrium between capillary filtration and lymphatic fluid removal is disturbed during pathological processes leading to inflammation, but also in hypoxia or due to alterations in vascular perfusion and coagulability. The degradation of the glycocalyx as the main component of the endothelial filtration barrier as well as pericyte disintegration results in the accumulation of interstitial and intracellular water. Moreover, lymphatic dysfunction evokes an increase in metabolic waste products, cytokines and inflammatory cells in the interstitial space contributing to myocardial oedema formation. This leads to myocardial stiffness and impaired contractility, eventually resulting in cardiomyocyte apoptosis, myocardial remodelling and fibrosis. The following article reviews pathophysiological inflammatory processes leading to myocardial oedema including myocarditis, ischaemia-reperfusion injury and viral infections with a special focus on the pathomechanisms evoked by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. In addition, clinical implications including potential long-term effects due to viral persistence (long COVID), as well as treatment options, are discussed.

Transient second-degree high-grade atrioventricular block caused by myocarditis

Myocarditis is an inflammatory disease of the heart muscle that most commonly occurs after infectious diseases in childhood. The clinical picture of acute myocarditis ranges from asymptomatic infection to fulminant heart failure and sudden death (1). Most of the patients may present with nonspecific symptoms such as respiratory distress, chest pain, nausea, and vomiting (2). While rhythm abnormalities such as ventricular and supraventricular rhythm disorders can be observed in these patients, various degrees of atrioventricular blocks may rarely develop (3). In this article, we aimed to present a patient who developed second-degree, high-grade atrioventricular block after myocarditis and recovered completely after treatment.

[Lethal lymphocytic myocarditis-an underestimated diagnosis in infancy and childhood?]

In the past, histological diagnosis of (post-)viral myocarditis was based on the so-called Dallas criteria, which have been criticized because of high interobserver variability and sampling error. Immunohistochemical qualification and quantification of interstitial intramyocardial leucocytes was established and standard values concerning adults were published. Fatal casualties due to a viral myocarditis are rare as far as babies and children are concerned (sudden unexpected death in infancy; SUDI). Cases of sudden unexpected death in the first year of life are frequently regarded as sudden infant death syndrome (SIDS). To diagnose myocarditis when there are only single focal lymphocytic infiltrates in the myocardium, the number of samples taken by autopsy is relevant. But even in babies, immunohistochemical qualification and quantification of interstitial lymphocytes and macrophages can lead to standard values allowing diagnosis of myocarditis. Depending on the course of a viral infection, molecular pathological detection of viral genome in the myocardium is possible to support the diagnosis. Using the mentioned methods gradually, there are more cases of suspected SIDS, which are in fact cases of virus-induced myocarditis as cause of death. Primary enteroviruses (coxsackie viruses) and adenoviruses were found but also Epstein-Barr virus and PVB-19.

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.

COVID-19 Vaccination and Cardiac Arrhythmias: A Review

PURPOSE OF REVIEW

In this review, we aim to delve into the existing literature, seeking to uncover the mechanisms, investigate the electrocardiographic changes, and examine the treatment methods of various cardiac arrhythmias that occur after administration of the COVID-19 vaccine.

RECENT FINDINGS

A global survey has exposed an incidence of arrhythmia in 18.27% of hospitalized COVID-19 patients. Furthermore, any type of COVID-19 vaccine - be it mRNA, adenovirus vector, whole inactivated, or protein subunit - appears to instigate cardiac arrhythmias. Among the cardiac adverse events reported post-COVID-19 vaccination, myocarditis emerges as the most common and is thought to be a potential cause of bradyarrhythmia. When a patient post-COVID-19 vaccination presents a suspicion of cardiac involvement, clinicians should perform a comprehensive history and physical examination, measure electrolyte levels, conduct ECG, and carry out necessary imaging studies. In our extensive literature search, we uncovered various potential mechanisms that might lead to cardiac conduction abnormalities and autonomic dysfunction in patients who have received the COVID-19 vaccine. These mechanisms encompass direct viral invasion through molecular mimicry/spike (S) protein production, an escalated inflammatory response, hypoxia, myocardial cell death, and the eventual scar/fibrosis. They correspond to a range of conditions including atrial tachyarrhythmias, bradyarrhythmia, ventricular arrhythmias, sudden cardiac death, and the frequently occurring myocarditis. For treating these COVID-19 vaccination-induced arrhythmias, we should incorporate general treatment strategies, similar to those applied to arrhythmias from other causes.

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.

Correlations between high sensitive troponin I and acute myocarditis extent in cardiac magnetic resonance imaging

PURPOSE

To assess the correlation between high sensitive troponin I (HsTnI) levels and myocardial damage on cardiac magnetic resonance (CMR) represented by late gadolinium enhancement (LGE) percentage in patients diagnosed with myocarditis.

METHODS

Retrospective analysis of consecutive patients who underwent CMR following a suspected diagnosis of acute myocarditis, comparing CMR findings viewed as LGE percentage and HsTnI levels.

RESULTS

Between February 2016 and December 2021, 101 patients underwent CMR for suspected myocarditis in Rambam Medical Center. Seventy-six (75.2%) patients with a documented diagnosis of acute myocarditis in the medical records based on clinical history and lab work were included in the final analysis. The median age was 30 years [interquartile range (IQR) 22,42] and 62 patients (81.6%) were male. Thirty-four patients (44.7%) had a history of fever and 26 (34.2%) had upper respiratory tract symptoms. The median maximal HsTnI was 3935 ng/l (1165,10 380) and the median C-reactive protein (CRP) was 7.97 mg/l (2.35,19.28). The median LGE percentage was 4.65% (2.6,8.5) and ventricular ejection fraction 60% (56.00,64.75).Linear association was found between LGE (%) and maximal HsTnI (ng/l) value with r  = 0.49 ( P  < 0.001). After including only patients in whom the CMR was performed within 5 days of the maximal HsTnI the correlation improved to r  = 0.67 ( P  < 0.001).

CONCLUSIONS

HsTnI is an indicator for myocardial damage extent resulting from inflammation in patients with acute myocarditis.

Myocarditis and Autoimmunity

INTRODUCTION

Autoimmune myocarditis may develop due to heterogeneous causes. Myocarditis is often caused by viral infections, but it can also be caused by systemic autoimmune diseases. Immune checkpoint inhibitors and virus vaccines induce immune activation, and they can cause the development of myocarditis, as well as several immune-related adverse events. The development of myocarditis is dependent on the genetic factors of the host, and the major histocompatibility complex (MHC) may be an important determinant of the type and severity of the disease. However, non-MHC immunoregulatory genes may also play a role in determining susceptibility.

AREA COVERED

This review summarizes the current knowledge of the etiology, pathogenesis, diagnosis and treatment of autoimmune myocarditis with a particular focus on viral infection and autoimmunity, and biomarkers of myocarditis.

EXPERT OPINION

An endomyocardial biopsy may not be the gold standard for the diagnosis of myocarditis. Cardiac magnetic resonance imaging is useful in diagnosing autoimmune myocarditis. Recently identified biomarkers of inflammation and myocyte injury are promising for the diagnosis of myocarditis when measured simultaneously. Future treatments should focus on the appropriate diagnosis of the etiologic agent, as well as on the specific stage of the evolution of immune and inflammatory processes.

Infectious diseases, autoantibodies, and autoimmunity

Infections are known to trigger flares of autoimmune diseases in humans and serve as an inciting cause of autoimmunity in animals. Evidence suggests a causative role of infections in triggering antigen-specific autoimmunity, previous thought mainly through antigen mimicry. However, an infection can induce bystander autoreactive T and B cell polyclonal activation, believed to result in non-pathogenic and pathogenic autoimmune responses. Lastly, epitope spreading in autoimmunity is a mechanism of epitope changes of autoreactive cells induced by infection, promoting the targeting of additional self-epitopes. This review highlights recent research findings, emphasizes infection-mediated autoimmune responses, and discusses the possible mechanisms involved.

Eukaryotic translation initiation factor eIF4G2 opens novel paths for protein synthesis in development, apoptosis and cell differentiation

Protein translation is a critical regulatory event involved in nearly all physiological and pathological processes. Eukaryotic translation initiation factors are dedicated to translation initiation, the most highly regulated stage of protein synthesis. Eukaryotic translation initiation factor 4G2 (eIF4G2, also called p97, NAT1 and DAP5), an eIF4G family member that lacks the binding sites for 5' cap binding protein eIF4E, is widely considered to be a key factor for internal ribosome entry sites (IRESs)-mediated cap-independent translation. However, recent findings demonstrate that eIF4G2 also supports many other translation initiation pathways. In this review, we summarize the role of eIF4G2 in a variety of cap-independent and -dependent translation initiation events. Additionally, we also update recent findings regarding the role of eIF4G2 in apoptosis, cell survival, cell differentiation and embryonic development. These studies reveal an emerging new picture of how eIF4G2 utilizes diverse translational mechanisms to regulate gene expression.

COVID-19 Associated Fulminant Myocarditis in a Fully-Vaccinated Female: A Case Report with Clinical Follow-up

Background

Myocarditis is considered a serious adverse event after COVID-19 infection. The risk and severity of myocarditis after COVID-19 disease decreased significantly in the vaccinated population. We present a case of cardiac magnetic resonance proven fulminant myocarditis following COVID-19 disease in a young female who was previously vaccinated with 2 doses of the BIBP (Sinopharm) vaccine.

Case summary

A 29-year-old female was referred to the hospital with acute chest pain, dyspnea, and nausea. Her electrocardiogram revealed ST-segment elevation in anterolateral leads with reciprocal changes in inferior leads. She was primarily diagnosed with ST-elevation myocardial infarction following spontaneous coronary artery dissection (SCAD) according to her age and gender. Her coronary angiography was normal. RT-PCR nasopharyngeal swab was positive for SARS-COV-2 infection. According to her history and excluding coronary artery diseases, she was clinically diagnosed with myocarditis and received corticosteroids, IVIG, and colchicine. She was discharged in a favorable condition after 11 days of hospitalization. Cardiac magnetic resonance imaging confirmed the diagnosis of myocarditis according to the updated lake Louise criteria. On her 4-month follow-up, she was asymptomatic, and her echocardiography showed improvement in biventricular function.

Discussion

The diagnosis of myocarditis caused by COVID-19 infection may be challenging as the symptoms of myocarditis, and COVID-19 disease may overlap. It should be considered when patients have acute chest pain, palpitation, elevated cardiac biomarkers, and new abnormalities in ECG or echocardiography. Cardiac MRI is a non-invasive gold standard modality for diagnosing and follow-up of myocarditis and should be used in clinically suspected myocarditis. The long-term course of myocarditis following COVID-19 disease is still unclear, but some evidence suggests it may have a favorable mid-term outcome.

Pathophysiological Mechanisms of Cardiac Dysfunction in Transgenic Mice with Viral Myocarditis

Viral myocarditis is pathologically associated with RNA viruses such as coxsackievirus B3 (CVB3), or more recently, with SARS-CoV-2, but despite intensive research, clinically proven treatment is limited. Here, by use of a transgenic mouse strain (TG) containing a CVB3ΔVP0 genome we unravel virus-mediated cardiac pathophysiological processes in vivo and in vitro. Cardiac function, pathologic ECG alterations, calcium homeostasis, intracellular organization and gene expression were significantly altered in transgenic mice. A marked alteration of mitochondrial structure and gene expression indicates mitochondrial impairment potentially contributing to cardiac contractile dysfunction. An extended picture on viral myocarditis emerges that may help to develop new treatment strategies and to counter cardiac failure.

Automatic classification of patients with myocardial infarction or myocarditis based only on clinical data: A quick response

BACKGROUND

In acute cardiovascular disease management, the delay between the admission in a hospital emergency department and the assessment of the disease from a Delayed Enhancement cardiac MRI (DE-MRI) scan is one of the barriers for an immediate management of patients with suspected myocardial infarction or myocarditis.

OBJECTIVES

This work targets patients who arrive at the hospital with chest pain and are suspected of having a myocardial infarction or a myocarditis. The main objective is to classify these patients based solely on clinical data in order to provide an early accurate diagnosis.

METHODS

Machine learning (ML) and ensemble approaches have been used to construct a framework to automatically classify the patients according to their clinical conditions. 10-fold cross-validation is used during the model's training to avoid overfitting. Approaches such as Stratified, Over-sampling, Under-sampling, NearMiss, and SMOTE were tested in order to address the imbalance of the data (i.e. proportion of cases per pathology). The ground truth is provided by a DE-MRI exam (normal exam, myocarditis or myocardial infarction).

RESULTS

The stacked generalization technique with Over-sampling seems to be the best one providing more than 97% of accuracy corresponding to 11 wrong classifications among 537 cases. Generally speaking, ensemble classifiers such as Stacking provided the best prediction. The five most important features are troponin, age, tobacco, sex and FEVG calculated from echocardiography.

CONCLUSION

Our study provides a reliable approach to classify the patients in emergency department between myocarditis, myocardial infarction or other patient condition from only clinical information, considering DE-MRI as ground-truth. Among the different machine learning and ensemble techniques tested, the stacked generalization technique is the best one providing an accuracy of 97.4%. This automatic classification could provide a quick answer before imaging exam such as cardiovascular MRI depending on the patient's condition.

Genetics of BAG3: A Paradigm for Developing Precision Therapies for Dilated Cardiomyopathies

Nonischemic dilated cardiomyopathy is a common form of heart muscle disease in which genetic factors play a critical etiological role. In this regard, both rare disease-causing mutations and common disease-susceptible variants, in the Bcl-2-associated athanogene 3 (BAG3) gene have been reported, highlighting the critical role of BAG3 in cardiomyocytes and in the development of dilated cardiomyopathy. The phenotypic effects of the BAG3 mutations help investigators understand the structure and function of the BAG3 gene. Indeed, we report herein that all of the known pathogenic/likely pathogenic variants affect at least 1 of 3 protein functional domains, ie, the WW domain, the second IPV (Ile-Pro-Val) domain, or the BAG domain, whereas none of the missense nontruncating pathogenic/likely pathogenic variants affect the proline-rich repeat (PXXP) domain. A common variant, p.Cys151Arg, associated with reduced susceptibility to dilated cardiomyopathy demonstrated a significant difference in allele frequencies among diverse human populations, suggesting evolutionary selective pressure. As BAG3-related therapies for heart failure move from the laboratory to the clinic, the ability to provide precision medicine will depend in large part on having a thorough understanding of the potential effects of both common and uncommon genetic variants on these target proteins. The current review article provides a roadmap that investigators can utilize to determine the potential interactions between a patient's genotype, their phenotype, and their response to therapeutic interventions with both gene delivery and small molecules.

CMV-associated carditis in a 5-month-old child

The article presents a case of cytomegalovirus-associated carditis in a 5-month-old child. Carditis proceeded in an arrhythmic form and was manifested by frequent ventricular extrasystoles. An increase in the activity of creatine-phosphokinase was noted in the blood. The isolation of cytomegalovirus DNA from the blood, as well as IgM and IgG to cytomegalovirus, made it possible to associate the development of carditis with IgG to cytomegalovirus. Carditis in a child proceeded without signs of heart failure. After diagnostic and therapeutic procedures, the child was discharged home. This case shows that one of the possible causes of carditis in children is cytomegalovirus, which necessitates testing for markers of active cytomegalovirus infection. In this age group, it is possible to register both congenital and acquired variants of infection with heart damage, having different treatment regimens and prognosis. 

The role of semaphorins in cardiovascular diseases: Potential therapeutic targets and novel biomarkers

Semaphorins (Semas), which belongs to the axonal guidance molecules, include 8 classes and could affect axon growth in the nervous system. Recently, semaphorins were found to regulate other pathophysiological processes, such as immune response, oncogenesis, tumor angiogenesis, and bone homeostasis, through binding with their plexin and neuropilin receptors. In this review, we summarized the detailed role of semaphorins and their receptors in the pathological progression of various cardiovascular diseases (CVDs), highlighting that semaphorins may be potential therapeutic targets and novel biomarkers for CVDs.

NMR-Based Metabolomic Analysis of Cardiac Tissues Clarifies Molecular Mechanisms of CVB3-Induced Viral Myocarditis and Dilated Cardiomyopathy

Viral myocarditis (VMC), which is defined as inflammation of the myocardium with consequent myocardial injury, may develop chronic disease eventually leading to dilated cardiomyopathy (DCM). Molecular mechanisms underlying the progression from acute VMC (aVMC), to chronic VMC (cVMC) and finally to DCM, are still unclear. Here, we established mouse models of VMC and DCM with Coxsackievirus B3 infection and conducted NMR-based metabolomic analysis of aqueous metabolites extracted from cardiac tissues of three histologically classified groups including aVMC, cVMC and DCM. We showed that these three pathological groups were metabolically distinct from their normal counterparts and identified three impaired metabolic pathways shared by these pathological groups relative to normal controls, including nicotinate and nicotinamide metabolism; alanine, aspartate and glutamate metabolism; and D-glutamine and D-glutamate metabolism. We also identified two extra impaired metabolic pathways in the aVMC group, including glycine, serine and threonine metabolism; and taurine and hypotaurine metabolism Furthermore, we identified potential cardiac biomarkers for metabolically distinguishing these three pathological stages from normal controls. Our results indicate that the metabolomic analysis of cardiac tissues can provide valuable insights into the molecular mechanisms underlying the progression from acute VMC to DCM.

The crucial role of cardiac MRI parameters in the prediction of outcomes in acute clinically suspected myocarditis: A functional and feature-tracking study

Background

The definitive diagnosis of myocarditis is made by endomyocardial biopsy, but it is an invasive method. Recent investigations have proposed that cardiac MRI parameters have both diagnostic and prognostic roles in assessing myocarditis. We aimed to evaluate the role of functional and feature-tracking (FT)-derived strain values in predicting major adverse cardiovascular events (MACE) in patients with acute myocarditis.

Methods and results

We evaluated 133 patients with acute myocarditis (74.4% men) between January 2016 and February 2021. During a mean follow-up of 31 ± 16 months, sixteen patients (12.03%) experienced MACE: three deaths (2.3%), nine ICD implantations (6.76%), and five cardiac transplantations (3.8%). The left ventricular ejection fraction (LVEF), the LV end-diastolic volume index (EDVI), and the LV global longitudinal strain (GLS) were the strongest predictors of MACE. Each 1-unit decline in LVEF and LVGLS or 1-unit rise in LVEDVI resulted in a 5, 24, and 2% increase in MACE, respectively. LVEF ≤36.46% and LVGLS ≤9% indicated MACE with 75% sensitivity and 74.4 and 73.5% specificity, respectively.

Conclusions

In a group of acute myocarditis patients with evidence of myocardial edema and late Gadolinium enhancement, LVEF and GLS were the strongest predictors of adverse cardiac events.

Clinical Profile and Predictors of Outcome in Children with Acute Fulminant Myocarditis Receiving Intensive Care: A Single Center Experience

Acute myocarditis in children is associated with high morbidity and mortality, with limited data on intravenous immunoglobulin (IVIG) treatment and outcome. Our goal was to describe clinical, treatment profile, and predictors of outcome in children with acute fulminant myocarditis (AFM) receiving intensive care. Case records of 120 children with clinical diagnosis of acute myocarditis from January 2008 to December 2018 were analyzed retrospectively. AFM was seen in 89 (74.2%) children of which nearly two-thirds (54 [60.7%]) were hypotensive at admission. The median (interquartile range [IQR]) ejection fraction on echocardiography was 25 (18.5–36%). Eighty-two children (68.3%) received IVIG. Intensive care needs were mechanical ventilation (n = 71; 59.2%) and inotrope support (n = 89; 74.2%); median inotrope score being 30 (IQR: 20–55). Twenty-one children died (17.5%). Fever (p = 0.004), arrhythmia (p = 0.03), shock (p = 0.015), higher inotrope score (p = 0.0001), need for ventilation (p = 0.025), acidosis (p = 0.013), AKI (p = 0.0001), transaminitis (p = 0.0001), and multiorgan dysfunction (p = 0.0001) were associated with mortality. The mortality was significantly less in IVIG treated group (12.1 vs. 28.9%; p = 0.02). On multiple logistic regression, MODS (p = 0.002) was independent predictor of mortality while IVIG treatment (p = 0.004) was favorably associated with survival. AFM complicated by multiorgan dysfunction carried a poor prognosis. IVIG was associated with survival benefit.

Case report: the role of multimodal imaging to optimize the timing of return to sports in an elite athlete with persistent COVID-19 myocardial inflammation

Background

COVID-19 has been associated with myocardial abnormalities on cardiac magnetic resonance imaging (CMR). We report a case of COVID-19 myocarditis in an elite athlete.

Case summary

A male, 21-year-old elite football player had tested positive for SARS-CoV-2 on a polymerase-chain-reaction test and was referred for cardiac evaluation after experiencing palpitations after returning to sports (RTS). Biochemical evaluation demonstrated elevated N-terminal pro b-type natriuretic peptide (NT-proBNP) and high-sensitive Troponin T. Echocardiography demonstrated left ventricular function within normal ranges for athletes but with diminished basal, posterolateral, and septal strain. Cardiac magnetic resonance imaging (CMR) showed increased T1 values and late gadolinium enhancement (LGE) in the basolateral and mid-ventricular posterior segments. Focal COVID-19 myocarditis was diagnosed and the patient remained restricted from sports, in line with the 2020 ESC sports cardiology guidelines. Two months later, his electrocardiogram (ECG) showed inferoposterolateral T-wave inversion (TWI). Serial imaging studies were performed to optimize RTS timing. Cardiac magnetic resonance imaging showed persistently increased T1/T2 values and persistent LGE at 5 and 7 months. At 9 months, 18 F-fluorodeoxyglucose (FDG)-positron emission tomography (PET)-computerized tomography (CT) demonstrated no pathologically increased cardiac FDG-uptake. Subsequent exercise ECG and Holters demonstrated no complex ventricular arrhythmias. The patient made a complete return to elite competitive sports, without any adverse events at 15 months of follow-up.

Discussion

Cardiac symptoms in athletes post-COVID-19 should prompt cardiac evaluation. As COVID-19 myocarditis inflammation can persist beyond the 3–6 months of recommended sports restriction, a more personalized approach to RTS timing can be warranted. In cases with myocardial oedema without other signs of inflammation, FDG-PET-CT can be of added value to assess active myocardial inflammation.

Veno-Arterial Extracorporeal Membrane Oxygenation in the Treatment of Hemodynamically Unstable Lupus Myocarditis: A Retrospective Case Series Study

Objective

The clinical manifestations and treatment of three patients with hemodynamically unstable lupus myocarditis (LM) were analyzed.

Methods

The clinical data of three patients with LM with hemodynamic instability, who were admitted to the emergency ICU of the south hospital of the Renji Hospital, School of Medicine, Shanghai Jiao Tong University of Medicine from January 2018 to December 2021, were collected and analyzed, and relevant literatures were reviewed.

Results

Two of the three patients had the first onset of systemic lupus erythematosus. The other patient had mixed connective tissue disease in the past, and lupus was the main manifestation of this disease. At the onset of the disease, all patients had chest tightness and shortness of breath; two patients had a fever, and the markers of myocardial injury increased. Cardiac color Doppler ultrasound indicated that left ventricular ejection fraction decreased significantly. Cardiac insufficiency with cardiogenic shock rapidly appeared as the main manifestation. Two patients immediately started veno-arterial extracorporeal membrane oxygenation (VA-ECMO), and ECMO was also started in one patient after a pacemaker placement was ineffective. For all three patients, high-dose hormones were given to control the primary disease, and then the ECMO machines were removed successfully.

Conclusion

VA-ECMO treatment should be implemented in patients with hemodynamically unstable LM as soon as possible to maintain the patient’s hemodynamics and help them overcome the crisis of cardiac dysfunction, allowing more time for primary disease treatment.

Galectin-3 and fibrosis intensity in Chronic Chagas Cardiomyopathy: a systematic review

Chronic Chagas Cardiomyopathy (CCC) is the most prevalent type of myocarditis and the main clinical form of the Chagas disease, which has peculiarities such as focal inflammation, structural derangement, hypertrophy, dilation, and intense reparative fibrosis. Many cellular compounds contribute to CCC development. Galectin-3 is a partaker in inflammation and contributes to myocardial fibrosis formation. Some studies showed the connection between Galectin-3 and fibrosis in Chagas disease but are still inconclusive on the guidance for the early implementation of pharmacological therapy. This systematic review evaluated Galectin-3 as a biomarker for fibrosis intensity in CCC. Two independent reviewers have searched five databases (PubMed, EMBASE, Cochrane Library, Scopus, and Lilacs), using the following search terms: galectin-3, biomarkers, fibrosis, Chagas cardiomyopathy, and Chagas disease. Overall, seven studies met the inclusion criteria and made up this review. There were four trials conducted through animal model experiments and three trials with humans. Experimental data in mice indicate an association between Galectin-3 expression and fibrosis in CCC (75% of studies). Data from human studies showed no direct connection between myocardial fibrosis and Galectin-3 expression (80% of studies). Thus, human findings do not provide significant evidence indicating that Galectin-3 is related to fibrosis formation in Chagas disease. Based on the analyzed studies, it is suggested that Galectin-3 might not be a good fibrosis marker in CCC.

Marijuana-induced myocarditis in a 24-year-old man

As marijuana, the most widely-used illicit drug in adolescents and adults, has some unknown side effects, marijuana abuse has become a public health concern. Also, marijuana affects different organs such as heart in its rate, rhythm and coronary flow; it eventually leads to events such as myocardial infarction and rarely myocarditis. A 24-year-old man without any medical history or cardiovascular risk factors presented with chest pain after marijuana consumption. Based on electrocardiogram, myocardial cytolysis and transthoracic echocardiography acute myocarditis diagnosis was established. A few days later, transthoracic echocardiography showed a small clot in apex with reduced left ventricle ejection fraction, in the absence of local akinesia. The patient was discharged with oral anticoagulant stable and without any symptoms. The myocarditis after marijuana abuse is rare. The physicians should include acute myocarditis in differential diagnosis of a patient with chest pain after using marijuana.

A Rare Case of Dilated Cardiomyopathy, Focal Segmental Glomerulosclerosis, and Bell’s Palsy in a 29-Year-Old Male After Coxsackievirus Infection

Dilated cardiomyopathy (DCM) is a severe myocardial disease with diversified etiologies. Coxsackievirus serotype B (CV-B) is a known cause of infectious myocarditis that leads to DCM. The pathogenesis of CV-B myocarditis is complex and involves a combination of tissue destruction from viral proliferation and host immune response. Diagnosis is based on clinical findings and the presence of post-infection elevated titers of IgM antibodies to CV-B. Echocardiography is an important imaging modality that plays a key role in diagnosing DCM. Rare complications of coxsackievirus infection may include facial paralysis and chronic kidney disease with nephrotic syndrome. Here we present a rare case of a 29-year-old-male with recent Bell’s palsy who presented with new-onset heart failure with left ventricular ejection fraction of 5% and focal segmental glomerulosclerosis nephrotic syndrome in the setting of elevated antibodies to CV-B.

Increased emergency cardiovascular events among under-40 population in Israel during vaccine rollout and third COVID-19 wave

Cardiovascular adverse conditions are caused by coronavirus disease 2019 (COVID-19) infections and reported as side-effects of the COVID-19 vaccines. Enriching current vaccine safety surveillance systems with additional data sources may improve the understanding of COVID-19 vaccine safety. Using a unique dataset from Israel National Emergency Medical Services (EMS) from 2019 to 2021, the study aims to evaluate the association between the volume of cardiac arrest and acute coronary syndrome EMS calls in the 16-39-year-old population with potential factors including COVID-19 infection and vaccination rates. An increase of over 25% was detected in both call types during January-May 2021, compared with the years 2019-2020. Using Negative Binomial regression models, the weekly emergency call counts were significantly associated with the rates of 1st and 2nd vaccine doses administered to this age group but were not with COVID-19 infection rates. While not establishing causal relationships, the findings raise concerns regarding vaccine-induced undetected severe cardiovascular side-effects and underscore the already established causal relationship between vaccines and myocarditis, a frequent cause of unexpected cardiac arrest in young individuals. Surveillance of potential vaccine side-effects and COVID-19 outcomes should incorporate EMS and other health data to identify public health trends (e.g., increased in EMS calls), and promptly investigate potential underlying causes.

4-nitrobenzoylcoumarin potentiates the antiparasitic, anti-inflammatory and cardioprotective effects of benznidazole in a murine model of acute Trypanosoma cruzi infection

The anti-inflammatory and cardioprotective potential of coumarin metabolites in infectious myocarditis remains overlooked. Thus, the impact of the synthetic 4-nitrobenzoylcoumarin (4NB) alone and combined with benznidazole (Bz) in a murine model of Trypanosoma cruzi-induced acute myocarditis was investigated. Swiss mice infected with T. cruzi were randomized in 8 groups: uninfected, infected untreated or treated with 50 and 100 mg/kg 4NB or Bz alone and combined. Treatments were administered by gavage for 20 days. Cytokines (IL-2, IL-6, IL-10, IL-17, TNFα, and IFN-γ), immunoglobulin reactivity index (total IgG, IgG1, IgG2a and IgG2b), atrial natriuretic peptide (ANP), parasitemia, serum transaminases, heart and liver cellularity were analyzed. T. cruzi infection induced blood parasitism, heart and liver inflammation, upregulated all cytokines, IgG reactivity index, ANP and transaminase levels, determining 43% mortality in untreated mice. Transaminase levels, mean parasitemia, heart inflammation and ANP were reduced in 4NB-treated mice, reaching a 100% survival rate. Total survival (100%) was also obtained in all combinations of Bz and 4NB, which were effective in reducing blood parasitism, transaminases, cytokines and ANP levels, IgG reactivity index, liver and heart interstitial cellularity compared to 50 mg/kg Bz. Our findings indicated that 4NB alone and combined with Bz was well tolerated, showing no evidence of hepatotoxicity. Mainly in combination, these drugs exerted protective effects against T. cruzi-induced acute myocarditis by attenuating blood parasitism, systemic and heart inflammation. Thus, combinations based on 4NB and Bz are potentially relevant to develop new and more effective drug regimens for the treatment of T. cruzi-induced myocarditis.

Dissecting the cellular landscape and transcriptome network in viral myocarditis by single-cell RNA sequencing

Coxsackievirus B3 (CVB3)-induced myocarditis is commonly employed to study viral pathogenesis in mice. Chronically affected mice may develop dilated cardiomyopathy, which may involve the mediation of immune and nonimmune cells. To dissect this complexity, we performed single-cell RNA sequencing on heart cells from healthy and myocarditic mice, leading us to note significant proportions of myeloid cells, T cells, and fibroblasts. Although the transcriptomes of myeloid cells were mainly of M2 phenotype, the Th17 cells, CTLs, and Treg cells had signatures critical for cytotoxic functions. Fibroblasts were heterogeneous expressing genes important in fibrosis and regulation of inflammation and immune responses. The intercellular communication networks revealed unique interactions and signaling pathways in the cardiac cellulome, whereas myeloid cells and T cells had upregulated unique transcription factors modulating cardiac remodeling functions. Together, our data suggest that M2 cells, T cells, and fibroblasts may cooperatively or independently participate in the pathogenesis of viral myocarditis.

Carditis After COVID-19 Vaccination With a Messenger RNA Vaccine and an Inactivated Virus Vaccine : A Case-Control Study

BACKGROUND

Case reports of carditis after BNT162b2 vaccination are accruing worldwide.

OBJECTIVE

To examine the association of BNT162b2 and CoronaVac (Sinovac) vaccination with carditis.

DESIGN

Case-control study with hospital control participants.

SETTING

Territory-wide, public health care database with linkage to population-based vaccination records in Hong Kong.

PATIENTS

Inpatients aged 12 years or older first diagnosed with carditis were selected as case patients. All other hospitalized patients without carditis were treated as control participants. Ten control participants were randomly matched with each case patient by age, sex, and admission date.

INTERVENTION

Vaccination with BNT162b2 or CoronaVac.

MEASUREMENTS

Incident diagnosis of carditis based on the International Classification of Diseases, Ninth Revision, and elevated troponin levels.

RESULTS

A total of 160 case patients and 1533 control participants were included. Incidence of carditis per 100 000 doses of CoronaVac and BNT162b2 administered was estimated to be 0.31 (95% CI, 0.13 to 0.66) and 0.57 (CI, 0.36 to 0.90), respectively. Multivariable analyses showed that recipients of the BNT162b2 vaccine had higher odds of carditis (adjusted odds ratio [OR], 3.57 [CI, 1.93 to 6.60]) than unvaccinated persons. Stratified by sex, the OR was 4.68 (CI, 2.25 to 9.71) for males and 2.22 (CI, 0.57 to 8.69) for females receiving the BNT162b2 vaccine. The ORs for adults and adolescents receiving the BNT162b2 vaccine were 2.41 (CI, 1.18 to 4.90) and 13.79 (CI, 2.86 to 110.38), respectively. Subanalysis showed an OR of 9.29 (CI, 3.94 to 21.91) for myocarditis and 1.06 (CI, 0.35 to 3.22) for pericarditis associated with BNT162b2. The risk was mainly seen after the second dose of BNT162b2 rather than the first. No association between CoronaVac and carditis with a magnitude similar to that for BNT162b2 was seen.

LIMITATION

Limited sample size, absence of electrocardiography and other clinical investigative data, and unrecorded overseas vaccination exposure.

CONCLUSION

Despite a low absolute risk, there is an increased risk for carditis associated with BNT162b2 vaccination. This elevated risk should be weighed against the benefits of vaccination.

PRIMARY FUNDING SOURCE

Health and Medical Research Fund.

Protein Kinase B2 (PKB2/AKT2) Is Essential for Host Protection in CVB3-Induced Acute Viral Myocarditis

Protein kinase B2 (AKT2) is involved in various cardiomyocyte signaling processes, including those important for survival and metabolism. Coxsackievirus B3 (CVB3) is one of the most common pathogens that cause myocarditis in humans. The role of AKT2 in CVB3 infection is not yet well understood. We used a cardiac-specific AKT2 knockout (KO) mouse to determine the role of AKT2 in CVB3-mediated myocarditis. CVB3 was injected intraperitoneally into wild-type (WT) and KO mice. The mice’s survival rate was recorded: survival in KO mice was significantly decreased compared with WT mice (WT vs. KO: 73.3 vs. 27.1%). Myocardial damage and inflammation were significantly increased in the hearts of KO mice compared with those of WT mice. Moreover, from surface ECG, AKT2 KO mice showed a prolonged atria and ventricle conduction time (PR interval, WT vs. KO: 47.27 ± 1.17 vs. 64.79 ± 7.17 ms). AKT2 deletion induced severe myocarditis and cardiac dysfunction due to CVB3 infection. According to real-time PCR, the mRNA level of IL-1, IL-6, and TNF-α decreased significantly in KO mice compared with WT mice on Days 5 after infection. In addition, innate immune response antiviral effectors, Type I interferon (interferon-α and β), and p62, were dramatically suppressed in the heart of KO mice. In particular, the adult cardiac myocytes isolated from the heart showed high induction of TLR4 protein in KO mice in comparison with WT. AKT2 deletion suppressed the activation of Type I interferon and p62 transcription in CVB3 infection. In cardiac myocytes, AKT2 is a key signaling molecule for the heart from damage through the activation of innate immunity during acute myocarditis.

CNN-KCL: Automatic myocarditis diagnosis using convolutional neural network combined with k-means clustering

Myocarditis is the form of an inflammation of the middle layer of the heart wall which is caused by a viral infection and can affect the heart muscle and its electrical system. It has remained one of the most challenging diagnoses in cardiology. Myocardial is the prime cause of unexpected death in approximately 20% of adults less than 40 years of age. Cardiac MRI (CMR) has been considered a noninvasive and golden standard diagnostic tool for suspected myocarditis and plays an indispensable role in diagnosing various cardiac diseases. However, the performance of CMR depends heavily on the clinical presentation and features such as chest pain, arrhythmia, and heart failure. Besides, other imaging factors like artifacts, technical errors, pulse sequence, acquisition parameters, contrast agent dose, and more importantly qualitatively visual interpretation can affect the result of the diagnosis. This paper introduces a new deep learning-based model called Convolutional Neural Network-Clustering (CNN-KCL) to diagnose Myocarditis. In this study, we used 47 subjects with a total number of 98,898 images to diagnose myocarditis disease. Our results demonstrate that the proposed method achieves an accuracy of 97.41% based on 10 fold-cross validation technique with 4 clusters for diagnosis of Myocarditis. To the best of our knowledge, this research is the first to use deep learning algorithms for the diagnosis of myocarditis.

Protective role of nutraceuticals against myocarditis

Myocarditis is an inflammatory disease of the myocardium that mostly affects young adults. The disease is commonly caused by viral infection, medications, autoimmune disorders, and inflammatory conditions. Nearly 50% of the cases of myocarditis are due to post-viral immune response in a setting of an identifiable or non-identifiable infection. The clinical manifestation is nonspecific ranging from asymptomatic courses to sudden death in infants and young patients. This review describes the properties of phytochemicals as plant-derived active ingredients which can be used in the prevention and treatment of myocarditis and its associated risk factors. Meanwhile, it has illustrated epidemiological analyses, mechanism of action, and the metabolism of phytochemicals in animal and human clinical trials. We also mentioned the precise mechanism of action by which phytochemicals elicit their anti-viral, anti-inflammatory, antioxidant, and immunomodulatory effects and how they regulate signal transduction pathways. Nevertheless, comprehensive clinical trials are required to study the properties of phytochemicals in vivo, in vitro, and in silico for a proper management of myocarditis. Our findings indicate that phytochemicals function as potent adjunctive therapeutic drugs in myocarditis and its related complications.

Differential Diagnosis of Fulminant Myocarditis and Acute Coronary Syndromes in the Case of Failure of Coronary Angiography: A Case Report

Fulminant myocarditis (FM) is a severe disease with a rapidly progressive and life-threatening course caused mainly by viral infection. The symptoms, laboratory findings, and presence of ECG changes resemble acute coronary syndrome. Therefore, coronary angiography is usually helpful in making the appropriate diagnosis. However, failure to obtain complete coronary artery images due to coronary artery anatomic variations poses a challenge for the diagnosis of FM. Here, we report a case of FM preliminarily diagnosed as acute coronary syndrome (ACS) due to the presence of coronary artery anomaly.

Comparison of ADAMTS Levels in Pulp Tissue Samples of Healthy and Symptomatic Irreversible Pulpitis Teeth

AIM

The aim of this study was to compare the levels of different ADAMTS (-1,-4, and -9) related to the breakdown of the proteoglycans and TIMP-3 levels that inhibit ADAMTS in the extra cellular matrix (ECM) of healthy pulp and symptomatic irreversible pulpitis.

METHODS

Pulp tissue samples diagnosed with healthy and symptomatic irreversible pulpitis were collected from 48 participants. Healthy and inflamed pulps were directly transferred to Eppendorf® tubes and stored at -80 °C (Nüve-DF490, Ankara, Türkiye) until further use. Routine root canal treatment procedures for the teeth were performed, after which the treatment process was completed. The levels of ADAMTS-1, ADAMTS-4, ADAMTS-9, and TIMP-3 were measured in supernatants of human dental pulp tissue extracts using ELISA kits (USCN, Wuhan, China). Independent sample t test and one-way analysis of variance (ANOVA) were used for parametric data, Kruskal-Wallis and Mann-Whitney U tests were used for non-parametric data.

RESULTS

There was a statistically significant difference between ADAMTS-1, ADAMTS-9 and TIMP-3 levels of the healthy pulp and pulpitis groups (p < 0.05), but there was no significant difference for ADAMTS-4 levels (p ˃ 0.05). It was found that the levels of ADAMTS-1 and ADAMTS-9 were higher in the pulpitis group compared to the healthy pulp group, while the TIMP-3 level decreased (p < 0.05).

CONCLUSION

As a result of this study, it was concluded that ADAMTS-1, ADAMTS-9 and TIMP-3 might have a role in pulpal inflammation, while ADAMTS-4 was not related to pulpal inflammation.

Clozapine-induced myocarditis: electronic health register analysis of incidence, timing, clinical markers and diagnostic accuracy

BACKGROUND

Clozapine is associated with increased risk of myocarditis. However, many common side-effects of clozapine overlap with the clinical manifestations of myocarditis. As a result, there is uncertainty about which signs, symptoms and investigations are important in distinguishing myocarditis from benign adverse effects of clozapine. Clarity on this issue is important, since missing a diagnosis of myocarditis or discontinuing clozapine unnecessarily may both have devastating consequences.

AIMS

To examine the clinical characteristics of clozapine-induced myocarditis and to identify which signs and symptoms distinguish true myocarditis from other clozapine adverse effects.

METHOD

A retrospective analysis of the record database for 247 621 patients was performed. A natural language processing algorithm identified the instances of patients in which myocarditis was suspected. The anonymised case notes for the patients of each suspected instance were then manually examined, and those whose instances were ambiguous were referred for an independent assessment by up to three cardiologists. Patients with suspected instances were classified as having confirmed myocarditis, myocarditis ruled out or undetermined.

RESULTS

Of 254 instances in 228 patients with suspected myocarditis, 11.4% (n = 29 instances) were confirmed as probable myocarditis. Troponin and C-reactive protein (CRP) had excellent diagnostic value (area under the curve 0.975 and 0.896, respectively), whereas tachycardia was of little diagnostic value. All confirmed instances occurred within 42 days of clozapine initiation.

CONCLUSIONS

Suspicion of myocarditis can lead to unnecessary discontinuation of clozapine. The 'critical period' for myocarditis emergence is the first 6 weeks, and clinical signs including tachycardia are of low specificity. Elevated CRP and troponin are the best markers for the need for further evaluation.

Advanced management of ventricular arrhythmias in chronic Chagas cardiomyopathy

Chagas cardiomyopathy is a parasitic infection caused by Trypanosoma cruzi. Structural and functional abnormalities are the result of direct myocardial damage by the parasite, immunological reactions, dysautonomia, and microvascular alterations. Chronic Chagas cardiomyopathy (CCC) is the most serious and important manifestation of the disease, affecting up to 30% of patients in the chronic phase. It results in heart failure, arrhythmias, thromboembolism, and sudden cardiac death. As in other cardiomyopathies, scar-related reentry frequently results in ventricular tachycardia (VT). The scars typically are located in the inferior and lateral aspects of the left ventricle close to the mitral annulus extending from endocardium to epicardium. The scars may be more prominent in the epicardium than in the endocardium, so epicardial mapping and ablation frequently are required. Identification of late potentials during sinus rhythm and mid-diastolic potentials during hemodynamically tolerated VT are the main targets for ablation. High-density mapping during sinus rhythm can identify late isochronal regions that are then targeted for ablation. Preablation cardiac magnetic resonance imaging with late enhancement can identify potentials areas of arrhythmogenesis. Therapeutic alternatives for VT management include antiarrhythmic drugs and modulation of the cardiac autonomic nervous system.