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Lancet (London, England) Feb 2012Myocarditis is an underdiagnosed cause of acute heart failure, sudden death, and chronic dilated cardiomyopathy. In developed countries, viral infections commonly cause... (Review)
Review
Myocarditis is an underdiagnosed cause of acute heart failure, sudden death, and chronic dilated cardiomyopathy. In developed countries, viral infections commonly cause myocarditis; however, in the developing world, rheumatic carditis, Trypanosoma cruzi, and bacterial infections such as diphtheria still contribute to the global burden of the disease. The short-term prognosis of acute myocarditis is usually good, but varies widely by cause. Those patients who initially recover might develop recurrent dilated cardiomyopathy and heart failure, sometimes years later. Because myocarditis presents with non-specific symptoms including chest pain, dyspnoea, and palpitations, it often mimics more common disorders such as coronary artery disease. In some patients, cardiac MRI and endomyocardial biopsy can help identify myocarditis, predict risk of cardiovascular events, and guide treatment. Finding effective therapies has been challenging because the pathogenesis of chronic dilated cardiomyopathy after viral myocarditis is complex and determined by host and viral genetics as well as environmental factors. Findings from recent clinical trials suggest that some patients with chronic inflammatory cardiomyopathy have a progressive clinical course despite standard medical care and might improve with a short course of immunosuppression.
Topics: Acute Disease; Bacterial Infections; Humans; Myocarditis; Prognosis; Virus Diseases
PubMed: 22185868
DOI: 10.1016/S0140-6736(11)60648-X -
Clinical Medicine (London, England) Sep 2021Acute myocarditis is a serious, likely underdiagnosed condition affecting people of all ages and for which the number of UK hospital admissions is rising. A primary... (Review)
Review
Acute myocarditis is a serious, likely underdiagnosed condition affecting people of all ages and for which the number of UK hospital admissions is rising. A primary diagnosis of myocarditis accounted for 0.04% (36.5 per 100,000) of all hospital admissions in England between 1998 and 2017, although this is likely to be an underestimate of the true burden of myocarditis. The aetiology is broad, including infective and inflammatory conditions as well as exposure to toxic agents. Clinical features are varied and overlap with other acute cardiac conditions making diagnosis a challenge. Cardiovascular magnetic resonance imaging currently serves as the gold standard non-invasive diagnostic modality. If an underlying aetiological process is identified, then therapy may be directed at the cause; however, for most, treatment is supportive and aimed at managing any complications such as heart failure or arrhythmias. There is emerging evidence for immunosuppressive therapy in certain cases. Prognosis is generally good with recovery in most; however, up to 30% with biopsy-proven myocarditis progress to develop a dilated cardiomyopathy and its potential associated complications. All-cause mortality in the UK for patients presenting to hospital with acute myocarditis is approximately 4%.
Topics: Acute Disease; Biopsy; Cardiomyopathy, Dilated; Heart; Humans; Myocarditis; Prognosis
PubMed: 34507935
DOI: 10.7861/clinmed.2021-0121 -
Journal of Cardiothoracic and Vascular... Jun 2020Viral myocarditis has an incidence rate of 10 to 22 per 100,000 individuals. The presentation pattern of viral myocarditis can range from nonspecific symptoms of fatigue... (Review)
Review
Viral myocarditis has an incidence rate of 10 to 22 per 100,000 individuals. The presentation pattern of viral myocarditis can range from nonspecific symptoms of fatigue and shortness of breath to more aggressive symptoms that mimic acute coronary syndrome. After the initial acute phase presentation of viral myocarditis, the virus may be cleared, resulting in full clinical recovery; the viral infection may persist; or the viral infection may lead to a persistent autoimmune-mediated inflammatory process with continuing symptoms of heart failure. As a result of these 3 possibilities, the diagnosis, prognosis, and treatment of viral myocarditis can be extremely unpredictable and challenging for the clinician. Herein, the incidence, etiology, definition and classification, clinical manifestation, diagnosis, pathogenesis, prognosis, and treatment of viral myocarditis are reviewed, and how acute clinical care teams might differentiate between viral myocarditis and other acute cardiac conditions is discussed.
Topics: Heart; Humans; Incidence; Myocarditis; Parvovirus B19, Human; Virus Diseases
PubMed: 32127272
DOI: 10.1053/j.jvca.2019.12.052 -
The Journal of Clinical Investigation Mar 2021Immune checkpoint inhibitors (ICIs) have transformed the treatment of various cancers, including malignancies once considered untreatable. These agents, however, are... (Review)
Review
Immune checkpoint inhibitors (ICIs) have transformed the treatment of various cancers, including malignancies once considered untreatable. These agents, however, are associated with inflammation and tissue damage in multiple organs. Myocarditis has emerged as a serious ICI-associated toxicity, because, while seemingly infrequent, it is often fulminant and lethal. The underlying basis of ICI-associated myocarditis is not completely understood. While the importance of T cells is clear, the inciting antigens, why they are recognized, and the mechanisms leading to cardiac cell injury remain poorly characterized. These issues underscore the need for basic and clinical studies to define pathogenesis, identify predictive biomarkers, improve diagnostic strategies, and develop effective treatments. An improved understanding of ICI-associated myocarditis will provide insights into the equilibrium between the immune and cardiovascular systems.
Topics: Biomarkers; Humans; Immune Checkpoint Inhibitors; Myocarditis
PubMed: 33645548
DOI: 10.1172/JCI145186 -
Circulation. Heart Failure Nov 2020Myocarditis is an inflammatory disease of the heart that may occur because of infections, immune system activation, or exposure to drugs. The diagnosis of myocarditis... (Review)
Review
Myocarditis is an inflammatory disease of the heart that may occur because of infections, immune system activation, or exposure to drugs. The diagnosis of myocarditis has changed due to the introduction of cardiac magnetic resonance imaging. We present an expert consensus document aimed to summarize the common terminology related to myocarditis meanwhile highlighting some areas of controversies and uncertainties and the unmet clinical needs. In fact, controversies persist regarding mechanisms that determine the transition from the initial trigger to myocardial inflammation and from acute myocardial damage to chronic ventricular dysfunction. It is still uncertain which viruses (besides enteroviruses) cause direct tissue damage, act as triggers for immune-mediated damage, or both. Regarding terminology, myocarditis can be characterized according to etiology, phase, and severity of the disease, predominant symptoms, and pathological findings. Clinically, acute myocarditis (AM) implies a short time elapsed from the onset of symptoms and diagnosis (generally <1 month). In contrast, chronic inflammatory cardiomyopathy indicates myocardial inflammation with established dilated cardiomyopathy or hypokinetic nondilated phenotype, which in the advanced stages evolves into fibrosis without detectable inflammation. Suggested diagnostic and treatment recommendations for AM and chronic inflammatory cardiomyopathy are mainly based on expert opinion given the lack of well-designed contemporary clinical studies in the field. We will provide a shared and practical approach to patient diagnosis and management, underlying differences between the European and US scientific statements on this topic. We explain the role of histology that defines subtypes of myocarditis and its prognostic and therapeutic implications.
Topics: Acute Disease; Cardiology; Chronic Disease; Consensus; Humans; Myocarditis; Predictive Value of Tests; Risk Factors; Terminology as Topic; Treatment Outcome
PubMed: 33176455
DOI: 10.1161/CIRCHEARTFAILURE.120.007405 -
Circulation Aug 2021Myocarditis remains a clinical challenge in pediatrics. Originally, it was recognized at autopsy before the application of endomyocardial biopsy, which led to a... (Review)
Review
Myocarditis remains a clinical challenge in pediatrics. Originally, it was recognized at autopsy before the application of endomyocardial biopsy, which led to a histopathology-based diagnosis such as in the Dallas criteria. Given the invasive and low-sensitivity nature of endomyocardial biopsy, its diagnostic focus shifted to a reliance on clinical suspicion. With the advances of cardiac magnetic resonance, an examination of the whole heart in vivo has gained acceptance in the pursuit of a diagnosis of myocarditis. The presentation may vary from minimal symptoms to heart failure, life-threatening arrhythmias, or cardiogenic shock. Outcomes span full resolution to chronic heart failure and the need for heart transplantation with inadequate clues to predict the disease trajectory. The American Heart Association commissioned this writing group to explore the current knowledge and management within the field of pediatric myocarditis. This statement highlights advances in our understanding of the immunopathogenesis, new and shifting dominant pathogeneses, modern laboratory testing, and use of mechanical circulatory support, with a special emphasis on innovations in cardiac magnetic resonance imaging. Despite these strides forward, we struggle without a universally accepted definition of myocarditis, which impedes progress in disease-targeted therapy.
Topics: Animals; Biopsy; Child; Clinical Decision-Making; Combined Modality Therapy; Disease Management; Disease Models, Animal; Disease Susceptibility; Humans; Multimodal Imaging; Myocarditis; Prognosis; Symptom Assessment; Treatment Outcome
PubMed: 34229446
DOI: 10.1161/CIR.0000000000001001 -
Expert Review of Cardiovascular Therapy Jun 2023Autoimmune myocarditis may develop due to heterogeneous causes. Myocarditis is often caused by viral infections, but it can also be caused by systemic autoimmune... (Review)
Review
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, 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.
Topics: Humans; Myocarditis; Autoimmunity; Inflammation; Biopsy; Biomarkers
PubMed: 37243585
DOI: 10.1080/14779072.2023.2219895 -
Heart Rhythm May 2019Many kinds of arrhythmias may occur in patients with myocarditis at any stage of the disease. However, compared to the other clinical presentations, arrhythmic... (Review)
Review
Many kinds of arrhythmias may occur in patients with myocarditis at any stage of the disease. However, compared to the other clinical presentations, arrhythmic myocarditis has been poorly described in the literature. Arrhythmias occurring in either ongoing or previous myocardial inflammation are complex and heterogeneous, and the disease itself is often underdiagnosed, thus limiting data collection and interpretation. However, different from the other clinical presentations, arrhythmic myocarditis requires specific diagnostic, prognostic, and therapeutic considerations. The aim of this review is to critically summarize the state of the art on myocarditis presenting with arrhythmias in terms of epidemiology, etiology, diagnosis, prognosis, and treatment.
Topics: Arrhythmias, Cardiac; Disease Management; Humans; Myocarditis; Prognosis
PubMed: 30476544
DOI: 10.1016/j.hrthm.2018.11.024 -
Circulation Research May 2019Myocarditis is generally a mild and self-limited consequence of systemic infection of cardiotropic viruses. However, patients can develop a temporary or permanent... (Review)
Review
Myocarditis is generally a mild and self-limited consequence of systemic infection of cardiotropic viruses. However, patients can develop a temporary or permanent impairment of cardiac function including acute cardiomyopathy with hemodynamic compromise or severe arrhythmias. In this setting, specific causes of inflammation are associated with variable risks of death and transplantation. Recent translational studies suggest that treatments tailored to specific causes of myocarditis may impact clinical outcomes when added to guideline-directed medical care. This review summarizes recent advances in translational research that influence the utility of endomyocardial biopsy for the management of inflammatory cardiomyopathies. Emerging therapies for myocarditis based on these mechanistic hypotheses are entering clinical trials and may add to the benefits of established heart failure treatment.
Topics: Animals; Cardiomyopathies; Disease Progression; Heart Failure; Humans; Myocarditis; Recovery of Function; Risk Factors; Treatment Outcome
PubMed: 31120823
DOI: 10.1161/CIRCRESAHA.118.313578 -
Nature Reviews. Cardiology Nov 2015Myocarditis--a frequent cause of dilated cardiomyopathy and sudden cardiac death--typically results from cardiotropic viral infection followed by active inflammatory... (Review)
Review
Myocarditis--a frequent cause of dilated cardiomyopathy and sudden cardiac death--typically results from cardiotropic viral infection followed by active inflammatory destruction of the myocardium. Characterization of this disease has been hampered by its heterogeneous clinical presentations and diverse aetiologies. Advances in cardiac MRI and molecular detection of viruses by endomyocardial biopsy have improved our ability to diagnose and understand the pathophysiological mechanisms of this elusive disease. However, therapeutic options are currently limited for both the acute and chronic phases of myocarditis. Several randomized, controlled trials have demonstrated potential benefit with immunosuppressive and immunomodulatory therapies, but further investigations are warranted. In this Review, we explore the pathophysiology, natural history, and modes of diagnosis of myocarditis, as well as evidence-based treatment strategies. As novel imaging techniques and human in vitro models of the disease emerge, the landscape of therapies for myocarditis is poised to improve.
Topics: Antiviral Agents; Humans; Myocarditis; Virus Diseases
PubMed: 26194549
DOI: 10.1038/nrcardio.2015.108