Myocarditis

Myocarditis is an inflammatory disease of the myocardium, which may occur alone or in association with a systemic process. There are numerous etiologies of myocarditis, but all lead to inflammation Inflammation Inflammation is a complex set of responses to infection and injury involving leukocytes as the principal cellular mediators in the body's defense against pathogenic organisms. Inflammation is also seen as a response to tissue injury in the process of wound healing. The 5 cardinal signs of inflammation are pain, heat, redness, swelling, and loss of function. Inflammation and myocyte injury, most often leading to signs and symptoms of heart failure. The course of myocarditis may vary based on the etiology and timeline of symptom progression. The diagnosis is supported by clinical findings, laboratory evaluation, and cardiac imaging. A definitive diagnosis by endomyocardial biopsy is rarely required. Management is supportive and aimed at addressing complications.

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Editorial responsibility: Stanley Oiseth, Lindsay Jones, Evelin Maza

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Overview

Definition

Myocarditis is an inflammatory disease of the myocardium.

Epidemiology

  • Incidence: approximately 10–22 cases per 100,000 people
  • About 1%–5% of viral infections involve the myocardium.
  • Affects more men than women
  • More common in young adults

Etiology

  • Idiopathic (50% of cases)
  • Infectious organisms:
    • Viral (most common in North America and Europe)
    • Bacterial
    • Protozoal (most common in Africa, Asia, and South America)
    • Fungal
  • Immune-mediated disorders:
    • Rheumatic fever Rheumatic fever Acute rheumatic fever (ARF) is an autoimmune inflammatory process that usually follows Streptococcal pharyngitis. Acute rheumatic fever usually occurs 2-4 weeks after an untreated infection and affects the heart, skin, joints, and nervous system. Rheumatic Fever
    • Allergic reactions
    • Transplant rejection
    • Kawasaki disease Kawasaki disease Kawasaki disease (KD), also known as mucocutaneous lymph node syndrome or infantile polyarteritis, is a medium-sized necrotizing febrile vasculitis that affects children < 5 years of age. Multiple systems are involved but the most serious is the predilection of the coronary arteries. Kawasaki Disease
    • Sarcoidosis Sarcoidosis Sarcoidosis is a multisystem inflammatory disease that causes noncaseating granulomas. The exact etiology is unknown. Sarcoidosis usually affects the lungs and thoracic lymph nodes, but it can also affect almost every system in the body, including the skin, heart, and eyes, most commonly. Sarcoidosis
    • Systemic lupus erythematosus Systemic lupus erythematosus Systemic lupus erythematosus (SLE) is a chronic autoimmune, inflammatory condition that causes immune-complex deposition in organs, resulting in systemic manifestations. Women, particularly those of African American descent, are more commonly affected. Systemic Lupus Erythematosus
    • Polymyositis Polymyositis Polymyositis (PM) is an autoimmune inflammatory myopathy caused by T cell-mediated muscle injury. The etiology of PM is unclear, but there are several genetic and environmental associations. Polymyositis is most common in middle-aged women and rarely affects children. Polymyositis
    • Dermatomyositis
    • Scleroderma Scleroderma Scleroderma (systemic sclerosis) is an autoimmune condition characterized by diffuse collagen deposition and fibrosis. The clinical presentation varies from limited skin involvement to diffuse involvement of internal organs. Scleroderma
    • Juvenile idiopathic arthritis Juvenile Idiopathic Arthritis Juvenile idiopathic arthritis (JIA), formerly known as juvenile rheumatoid arthritis, is a heterogeneous group of inflammatory diseases characterized by inflammation of 1 or more joints and is the most common pediatric rheumatic disease. Juvenile Idiopathic Arthritis
    • Vasculitis
  • Exogenous agents
  • Genetic predisposition:
    • Genetic defects in the structural proteins of myocytes
    • ↑ Susceptibility to myocyte damage
  • Environmental causes:
    • Exposure to carbon monoxide
    • Heavy-metal toxicity
    • Black widow venom
  • Drugs:
    • Doxorubicin
    • Cyclophosphamide
    • Cocaine
    • Amphetamines
    • Ethanol

Causes of infectious myocarditis

The following table summarizes the infectious causes of myocarditis. Keep in mind that this list is not exhaustive.

Table: Causes of infectious myocarditis
Viral Bacterial Parasitic Fungal
  • Coxsackie B virus Virus Viruses are infectious, obligate intracellular parasites composed of a nucleic acid core surrounded by a protein capsid. Viruses can be either naked (non-enveloped) or enveloped. The classification of viruses is complex and based on many factors, including type and structure of the nucleoid and capsid, the presence of an envelope, the replication cycle, and the host range. Virology: Overview
  • Adenovirus Adenovirus Adenovirus (member of the family Adenoviridae) is a nonenveloped, double-stranded DNA virus. Adenovirus is transmitted in a variety of ways, and it can have various presentations based on the site of entry. Presentation can include febrile pharyngitis, conjunctivitis, acute respiratory disease, atypical pneumonia, and gastroenteritis. Adenovirus
  • Parvovirus B19 Parvovirus B19 Primate erythroparvovirus 1 (generally referred to as parvovirus B19, B19 virus, or sometimes erythrovirus B19) ranks among the smallest DNA viruses. Parvovirus B19 is of the family Parvoviridae and genus Erythrovirus. In immunocompetent humans, parvovirus B19 classically results in erythema infectiosum (5th disease) or "slapped cheek syndrome." Parvovirus B19
  • Human herpesvirus 6
  • Epstein-Barr virus Epstein-Barr Virus Epstein-Barr virus (EBV) is a linear, double-stranded DNA virus belonging to the Herpesviridae family. This highly prevalent virus is mostly transmitted through contact with oropharyngeal secretions from an infected individual. The virus can infect epithelial cells and B lymphocytes, where it can undergo lytic replication or latency. Epstein-Barr Virus
  • Cytomegalovirus Cytomegalovirus CMV is a ubiquitous double-stranded DNA virus belonging to the Herpesviridae family. CMV infections can be transmitted in bodily fluids, such as blood, saliva, urine, semen, and breast milk. The initial infection is usually asymptomatic in the immunocompetent host, or it can present with symptoms of mononucleosis. Cytomegalovirus
  • Hepatitis C Hepatitis C Hepatitis C is an infection of the liver caused by the hepatitis C virus (HCV). The infection can be transmitted through infectious blood or body fluids and may be transmitted during childbirth or through IV drug use or sexual intercourse. Hepatitis C virus can cause both acute and chronic hepatitis, ranging from a mild to a serious, lifelong illness including liver cirrhosis and hepatocellular carcinoma (HCC). Hepatitis C Virus
  • Influenza Influenza Influenza viruses are members of the Orthomyxoviridae family and the causative organisms of influenza, a highly contagious febrile respiratory disease. There are 3 primary influenza viruses (A, B, and C) and various subtypes, which are classified based on their virulent surface antigens, hemagglutinin (HA) and neuraminidase (NA). Influenza typically presents with a fever, myalgia, headache, and symptoms of an upper respiratory infection. Influenza Viruses/Influenza
  • Poliovirus Poliovirus Poliomyelitis is an infectious disease caused by the poliovirus. This virus is a member of the Picornaviridae family. It is a small, single-stranded, positive-sense RNA virus without a lipid envelope. Transmission occurs through the fecal-oral route and, occasionally, through respiratory aerosols. Poliovirus/Poliomyelitis
  • HIV
  • Borrelia Borrelia Borrelia are gram-negative microaerophilic spirochetes. Owing to their small size, they are not easily seen on Gram stain but can be visualized using dark-field microscopy, Giemsa, or Wright stain. Spirochetes are motile and move in a characteristic spinning fashion due to axial filaments in the periplasmic space. Borrelia burgdorferi
  • Mycoplasma Mycoplasma Mycoplasma is a species of pleomorphic bacteria that lack a cell wall, which makes them difficult to target with conventional antibiotics and causes them to not gram stain well. Mycoplasma bacteria commonly target the respiratory and urogenital epithelium. Mycoplasma pneumoniae (M. pneumoniae), the causative agent of atypical or "walking" pneumonia. Mycoplasma pneumoniae
  • Mycobacterium Mycobacterium Mycobacterium is a genus of the family Mycobacteriaceae in the phylum Actinobacteria. Mycobacteria comprise more than 150 species of facultative intracellular bacilli that are mostly obligate aerobes. Mycobacteria are responsible for multiple human infections including serious diseases, such as tuberculosis (M. tuberculosis), leprosy (M. leprae), and M. avium complex infections. Mycobacterium tuberculosis Tuberculosis Tuberculosis (TB) is an infectious disease caused by Mycobacterium tuberculosis complex bacteria. The bacteria usually attack the lungs but can also damage other parts of the body. Approximately 30% of people around the world are infected with this pathogen, with the majority harboring a latent infection. Tuberculosis spreads through the air when a person with active pulmonary infection coughs or sneezes. Tuberculosis
  • Corynebacterium Corynebacterium Corynebacteria are gram-positive, club-shaped bacilli. Corynebacteria are commonly isolated on tellurite or Loeffler's media and have characteristic metachromatic granules. The major pathogenic species is Corynebacterium diphtheriae, which causes a severe respiratory infection called diphtheria. Corynebacterium diphtheriae
  • Staphylococcus Staphylococcus Staphylococcus is a medically important genera of Gram-positive, aerobic cocci. These bacteria form clusters resembling grapes on culture plates. Staphylococci are ubiquitous for humans, and many strains compose the normal skin flora. Staphylococcus
  • Neisseria Neisseria Neisseria is a genus of bacteria commonly present on mucosal surfaces. Several species exist, but only 2 are pathogenic to humans: N. gonorrhoeae and N. meningitidis. Neisseria species are non-motile, gram-negative diplococci most commonly isolated on modified Thayer-Martin (MTM) agar. Neisseria gonorrhoeae
  • Streptococcus Streptococcus Streptococcus is one of the two medically important genera of gram-positive cocci, the other being Staphylococcus. Streptococci are identified as different species on blood agar on the basis of their hemolytic pattern and sensitivity to optochin and bacitracin. There are many pathogenic species of streptococci, including S. pyogenes, S. agalactiae, S. pneumoniae, and the viridans streptococci. Streptococcus
  • Brucella Brucella Brucellosis (also known as undulant fever, Mediterranean fever, or Malta fever) is a zoonotic infection that spreads predominantly through ingestion of unpasteurized dairy products or direct contact with infected animal products. Clinical manifestations include fever, arthralgias, malaise, lymphadenopathy, and hepatosplenomegaly. Brucella/Brucellosis
  • Haemophilus Haemophilus Haemophilus is a genus of Gram-negative coccobacilli, all of whose strains require at least 1 of 2 factors for growth (factor V [NAD] and factor X [heme]); therefore, it is most often isolated on chocolate agar, which can supply both factors. The pathogenic species are H. influenzae and H. ducreyi. Haemophilus influenzae
  • Treponema Treponema Treponema is a gram-negative, microaerophilic spirochete. Owing to its very thin structure, it is not easily seen on Gram stain, but can be visualized using dark-field microscopy. This spirochete contains endoflagella, which allow for a characteristic corkscrew movement. Treponema pallidum
  • Coxiella burnetti
  • Rickettsia Rickettsia Rickettsiae are a diverse collection of obligate intracellular, gram-negative bacteria that have a tropism for vascular endothelial cells. The vectors for transmission vary by species but include ticks, fleas, mites, and lice. Rickettsia rickettsii
  • Trypanosoma cruzi Trypanosoma cruzi Chagas disease is an infection caused by the American trypanosome Trypanosoma cruzi. This parasitic protozoan is transmitted in the feces of reduviid bugs in South and Central America. Acute infection may present with inflammation at the inoculation site (chagoma), fever, and lymphadenopathy. Untreated, chronic infection can progress to severe complications. Trypanosoma cruzi/Chagas disease
  • Toxoplasma Toxoplasma Toxoplasmosis is an infectious disease caused by Toxoplasma gondii, an obligate intracellular protozoan parasite. Felines are the definitive host, but transmission to humans can occur through contact with cat feces or the consumption of contaminated foods. The clinical presentation and complications depend on the host's immune status. Toxoplasma/Toxoplasmosis gondii
  • Entamoeba histolytica
  • Leishmania Leishmania Leishmania species are obligate intracellular parasites that are transmitted by an infected sandfly. The disease is endemic to Asia, the Middle East, Africa, the Mediterranean, and South and Central America. Clinical presentation varies, dependent on the pathogenicity of the species and the host's immune response. Leishmania/Leishmaniasis
  • Aspergillus
  • Candida Candida Candida is a genus of dimorphic, opportunistic fungi. Candida albicans is part of the normal human flora and is the most common cause of candidiasis. The clinical presentation varies and can include localized mucocutaneous infections (e.g., oropharyngeal, esophageal, intertriginous, and vulvovaginal candidiasis) and invasive disease (e.g., candidemia, intraabdominal abscess, pericarditis, and meningitis). Candida/Candidiasis
  • Actinomyces Actinomyces Actinomyces is an anaerobic, gram-positive, branching, filamentous rod. Actinomyces israelii is the most common species involved in human disease. The organism is commonly found as part of the normal flora in the oral cavity, gastrointestinal tract, and reproductive tract. Actinomyces/Actinomycosis
  • Blastomyces Blastomyces Blastomycosis is an infection caused by inhalation of the spores of the fungus, Blastomyces. Blastomyces species thrive in moist soil and decaying material and are common in the Ohio and Mississippi River valleys and the Great Lakes regions of the United States and Canada. Although most patients are asymptomatic, some can develop pneumonia. Blastomyces/Blastomycosis
  • Coccidioides Coccidioides Coccidioidomycosis, commonly known as San Joaquin Valley fever, is a fungal disease caused by Coccidioides immitis or Coccidioides posadasii. When Coccidioides spores are inhaled, they transform into spherules that result in infection. Coccidioidomycosis is also a common cause of community-acquired pneumonia and can cause severe disease in the immunocompromised. Coccidioides/Coccidioidomycosis
  • Histoplasma Histoplasma Histoplasmosis is an infection caused by Histoplasma capsulatum, a dimorphic fungus. The fungus exists as a mold at low temperatures and as yeast at high temperatures. H. capsulatum is the most common endemic fungal infection in the US and is most prevalent in the midwestern and central states along the Ohio and Mississippi River valleys. Histoplasma/Histoplasmosis
  • Cryptococcus Cryptococcus Cryptococcosis is an opportunistic, fungal infection caused by the Cryptococcus species. The principal pathogens in humans are C. neoformans (primary) and C. gattii. Cryptococcus neoformans is typically found in pigeon droppings and acquired by inhaling dust from contaminated soil. The majority of affected patients are immunocompromised. Cryptococcus/Cryptococcosis
  • Mucormyocises
  • Nocardia Nocardia Nocardia is a branching, filamentous, gram-positive bacilli. It is partially acid fast due to the presence of mycolic acids in the cell wall. Nocardia is a ubiquitous soil organism that most commonly affects immunocompromised patients. Nocardia is transmitted via inhalation of aerosolized bacteria or less commonly, via direct contact with wounds. Nocardia/Nocardiosis

Pathophysiology

Inflammation due to various etiologies leads to enlargement of the heart and dilation of all chambers.

  • Causes of myocyte injury:
    • Viral: direct viral toxicity, lymphocytic infiltration, and cytokines
    • Bacterial: direct invasion or bacterial toxins
    • Autoimmune: autoantibodies to myocyte components
    • Toxins: hypersensitivity or direct effects
  • Myocardial inflammation Inflammation Inflammation is a complex set of responses to infection and injury involving leukocytes as the principal cellular mediators in the body's defense against pathogenic organisms. Inflammation is also seen as a response to tissue injury in the process of wound healing. The 5 cardinal signs of inflammation are pain, heat, redness, swelling, and loss of function. Inflammation and injury → myocardial necrosis
  • Severe and prolonged damage → fibrosis → chamber remodeling → dilated cardiomyopathy Dilated Cardiomyopathy Dilated cardiomyopathy (DCM) is the most common type of non-ischemic cardiomyopathy and a common cause of heart failure (HF). The cause may be idiopathic, familial, or secondary to a variety of underlying conditions. The disease is characterized by the enlargement of 1 or both ventricles and reduced systolic function. Dilated Cardiomyopathy
  • Consequences:
    • Heart failure
    • Cardiac arrhythmia
    • Extension to the pericardium → pericarditis Pericarditis Pericarditis is an inflammation of the pericardium, often with fluid accumulation. It can be caused by infection (often viral), myocardial infarction, drugs, malignancies, metabolic disorders, autoimmune disorders, or trauma. Acute, subacute, and chronic forms exist. Pericarditis

Clinical Presentation

The clinical presentation can vary based on the severity and temporal progression of symptoms. Most signs and symptoms are related to heart failure.

Classification

Myocarditis is classified based on temporal progression.

  • Subclinical: absent or minimal symptoms
  • Acute: heart failure develops in < 3 months.
  • Chronic: heart failure develops in > 3 months.

Symptoms

  • Fever
  • Chest pain Chest Pain Chest pain is one of the most common and challenging complaints that may present in an inpatient and outpatient setting. The differential diagnosis of chest pain is large and includes cardiac, gastrointestinal, pulmonary, musculoskeletal, and psychiatric etiologies. Chest Pain
  • Dyspnea Dyspnea Dyspnea is the subjective sensation of breathing discomfort. Dyspnea is a normal manifestation of heavy physical or psychological exertion, but also may be caused by underlying conditions (both pulmonary and extrapulmonary). Dyspnea
  • Orthopnea
  • Loss of appetite
  • Abdominal pain Pain Pain has accompanied humans since they first existed, first lamented as the curse of existence and later understood as an adaptive mechanism that ensures survival. Pain is the most common symptomatic complaint and the main reason why people seek medical care. Physiology of Pain
  • Fatigue
  • Decreased exercise tolerance

Physical exam

  • Tachycardia
  • Arrhythmia
  • Peripheral edema Edema Edema is a condition in which excess serous fluid accumulates in the body cavity or interstitial space of connective tissues. Edema is a symptom observed in several medical conditions. It can be categorized into 2 types, namely, peripheral (in the extremities) and internal (in an organ or body cavity). Edema
  • Hepatomegaly
  • Pulmonary rales
  • Jugular venous distention
  • Murmur → may indicate chamber enlargement:
    • Mitral regurgitation Mitral regurgitation Mitral regurgitation (MR) is the backflow of blood from the left ventricle (LV) to the left atrium (LA) during systole. Mitral regurgitation may be acute (myocardial infarction) or chronic (myxomatous degeneration). Acute and decompensated chronic MR can lead to pulmonary venous congestion, resulting in symptoms of dyspnea, orthopnea, and fatigue. Mitral Regurgitation
    • Tricuspid regurgitation Tricuspid regurgitation Tricuspid regurgitation (TR) is a valvular defect that allows backflow of blood from the right ventricle to the right atrium during systole. Tricuspid regurgitation can develop through a number of cardiac conditions that cause dilation of the right ventricle and tricuspid annulus. A blowing holosystolic murmur is best heard at the left lower sternal border. Tricuspid Regurgitation
  • S3 and S4 gallops
  • Pericardial friction rub ( pericarditis Pericarditis Pericarditis is an inflammation of the pericardium, often with fluid accumulation. It can be caused by infection (often viral), myocardial infarction, drugs, malignancies, metabolic disorders, autoimmune disorders, or trauma. Acute, subacute, and chronic forms exist. Pericarditis)

Complications

  • Cardiogenic shock Shock Shock is a life-threatening condition associated with impaired circulation that results in tissue hypoxia. The different types of shock are based on the underlying cause: distributive (↑ cardiac output (CO), ↓ systemic vascular resistance (SVR)), cardiogenic (↓ CO, ↑ SVR), hypovolemic (↓ CO, ↑ SVR), obstructive (↓ CO), and mixed. Types of Shock
  • Myocardial infarction Myocardial infarction MI is ischemia and death of an area of myocardial tissue due to insufficient blood flow and oxygenation, usually from thrombus formation on a ruptured atherosclerotic plaque in the epicardial arteries. Clinical presentation is most commonly with chest pain, but women and patients with diabetes may have atypical symptoms. Myocardial Infarction
  • Dilated cardiomyopathy
  • Cardiac arrhythmias
  • Mural thrombus with systemic emboli
  • Sudden cardiac arrest Cardiac arrest Cardiac arrest is the sudden, complete cessation of cardiac output with hemodynamic collapse. Patients present as pulseless, unresponsive, and apneic. Rhythms associated with cardiac arrest are ventricular fibrillation/tachycardia, asystole, or pulseless electrical activity. Cardiac Arrest

Diagnosis

Initial evaluation

Laboratory studies:

  • ↑ Erythrocyte sedimentation rate
  • ↑ CRP
  • ↑ Troponin
  • ↑ Natriuretic peptide
  • Viral testing may aid in identifying the causative agent.
  • Rheumatological screening for autoimmune causes

ECG ECG An electrocardiogram (ECG) is a graphic representation of the electrical activity of the heart plotted against time. Adhesive electrodes are affixed to the skin surface allowing measurement of cardiac impulses from many angles. The ECG provides 3-dimensional information about the conduction system of the heart, the myocardium, and other cardiac structures. Normal Electrocardiogram (ECG):

  • ST changes:
    • Often nonspecific
    • Diffuse ST elevation signals seen in pericarditis Pericarditis Pericarditis is an inflammation of the pericardium, often with fluid accumulation. It can be caused by infection (often viral), myocardial infarction, drugs, malignancies, metabolic disorders, autoimmune disorders, or trauma. Acute, subacute, and chronic forms exist. Pericarditis
  • Arrhythmia
  • Conduction delays

Chest X-ray:

  • Normal to enlarged heart
  • Indications of heart failure:
    • Pulmonary venous congestion
    • Pleural effusion Pleural Effusion Pleural effusion refers to the accumulation of fluid between the layers of the parietal and visceral pleura. Common causes of this condition include infection, malignancy, autoimmune disorders, or volume overload. Clinical manifestations include chest pain, cough, and dyspnea. Pleural Effusion

Cardiac imaging

Echocardiogram:

  • Should be performed in all patients with suspected myocarditis
  • May be normal in early or mild disease
  • Possible findings:
    • Left ventricular dilation
    • Ventricular systolic dysfunction
    • Mitral or tricuspid regurgitation
    • Pericardial effusion Pericardial effusion Pericardial effusion is the accumulation of excess fluid in the pericardial space around the heart. The pericardium does not easily expand; thus, rapid fluid accumulation leads to increased pressure around the heart. The increase in pressure restricts cardiac filling, resulting in decreased cardiac output and cardiac tamponade. Pericardial Effusion and Cardiac Tamponade
    • Intracardiac thrombi
  • Excludes other causes of heart failure
Transthoracic echocardiogram images for a patient with myocarditis

Transthoracic echocardiogram images for a patient with myocarditis:
(A) Long axis view and (B) short axis view demonstrating a pericardial effusion (marked in blue)

Image: “Recurrent lymphocytic myocarditis in a young male with ulcerative colitis Ulcerative colitis Ulcerative colitis (UC) is an idiopathic inflammatory condition that involves the mucosal surface of the colon. It is a type of inflammatory bowel disease (IBD), along with Crohn's disease (CD). The rectum is always involved, and inflammation may extend proximally through the colon. Ulcerative Colitis” by Varnavas, V.C. et al. License: CC BY 2.0

Cardiac MRI:

  • Characteristic enhancement of the myocardial wall
  • Myocardial edema Edema Edema is a condition in which excess serous fluid accumulates in the body cavity or interstitial space of connective tissues. Edema is a symptom observed in several medical conditions. It can be categorized into 2 types, namely, peripheral (in the extremities) and internal (in an organ or body cavity). Edema
  • Myocardial hyperemia

Endomyocardial biopsy

Endomyocardial biopsy is the gold standard for diagnosis; however, it is rarely needed.

Indications:

  • Acute deterioration of cardiac function without a known etiology
  • Failure to respond to therapy

Findings:

  • Cellular infiltrates may be:
    • Lymphocytic
    • Eosinophilic
    • Neutrophilic
    • Mononuclear
  • Myocyte necrosis
  • Interstitial fibrosis
  • Myofiber hypertrophy
  • Granulomatous changes:
    • Mycobacterium Mycobacterium Mycobacterium is a genus of the family Mycobacteriaceae in the phylum Actinobacteria. Mycobacteria comprise more than 150 species of facultative intracellular bacilli that are mostly obligate aerobes. Mycobacteria are responsible for multiple human infections including serious diseases, such as tuberculosis (M. tuberculosis), leprosy (M. leprae), and M. avium complex infections. Mycobacterium
    • Fungi
    • Parasitic
    • Sarcoid myocarditis (noncaseating)
  • Giant cells: giant-cell myocarditis

Management

General principles

Management for myocarditis is generally supportive, but often includes:

  • Heart failure management
  • Arrhythmia management
  • Treating the underlying etiology (when possible)

Heart failure management

Medical therapy for heart failure:

  • Diuretics
  • ACE inhibitors
  • Beta-adrenergic blockers
  • Angiotensin II receptor blockers
  • Aldosterone antagonists

For fulminant heart failure:

  • Inotropic support
  • Intraaortic balloon pump
  • Left ventricular assist device
  • Cardiac transplantation

Arrhythmia management

  • Antiarrhythmic therapy
  • Cardioversion
  • Temporary or permanent pacing

Other considerations

  • Anticoagulants Anticoagulants Anticoagulants are drugs that retard or interrupt the coagulation cascade. The primary classes of available anticoagulants include heparins, vitamin K-dependent antagonists (e.g., warfarin), direct thrombin inhibitors, and factor Xa inhibitors. Anticoagulants are indicated for:
    • Intracardiac thrombi
    • Evidence of systemic embolism
    • Atrial fibrillation Atrial fibrillation Atrial fibrillation (AF or Afib) is a supraventricular tachyarrhythmia and the most common kind of arrhythmia. It is caused by rapid, uncontrolled atrial contractions and uncoordinated ventricular responses. Atrial Fibrillation
  • Avoidance of:
    • NSAIDs
    • Alcohol consumption
    • Exercise

Long term follow-up

Most patients will have a partial or full recovery. However, long-term follow-up and monitoring are recommended.

  • Gradual resumption of physical activities
  • Serial echocardiography monitoring
  • Re-evaluation and titration of medications, as appropriate

Related videos

Differential Diagnosis

  • Pericarditis: an inflammation Inflammation Inflammation is a complex set of responses to infection and injury involving leukocytes as the principal cellular mediators in the body's defense against pathogenic organisms. Inflammation is also seen as a response to tissue injury in the process of wound healing. The 5 cardinal signs of inflammation are pain, heat, redness, swelling, and loss of function. Inflammation of the outer lining of the heart resulting from infection, autoimmune disease, radiation, surgery, or myocardial infarction. Pericarditis clinically presents with fever Fever Fever is defined as a measured body temperature of at least 38°C (100.4°F). Fever is caused by circulating endogenous and/or exogenous pyrogens that increase levels of prostaglandin E2 in the hypothalamus. Fever is commonly associated with chills, rigors, sweating, and flushing of the skin. Fever and pleuritic chest pain Pain Pain has accompanied humans since they first existed, first lamented as the curse of existence and later understood as an adaptive mechanism that ensures survival. Pain is the most common symptomatic complaint and the main reason why people seek medical care. Physiology of Pain that increases with lying supine, and pericardial rub on auscultation. An ECG ECG An electrocardiogram (ECG) is a graphic representation of the electrical activity of the heart plotted against time. Adhesive electrodes are affixed to the skin surface allowing measurement of cardiac impulses from many angles. The ECG provides 3-dimensional information about the conduction system of the heart, the myocardium, and other cardiac structures. Normal Electrocardiogram (ECG) with diffuse ST-segment elevation and an echocardiogram showing pericardial effusion can confirm the diagnosis. Management is supportive.
  • Myocardial infarction Myocardial infarction MI is ischemia and death of an area of myocardial tissue due to insufficient blood flow and oxygenation, usually from thrombus formation on a ruptured atherosclerotic plaque in the epicardial arteries. Clinical presentation is most commonly with chest pain, but women and patients with diabetes may have atypical symptoms. Myocardial Infarction: ischemia of the myocardium due to partial or complete obstruction of the coronary arteries Arteries Arteries are tubular collections of cells that transport oxygenated blood and nutrients from the heart to the tissues of the body. The blood passes through the arteries in order of decreasing luminal diameter, starting in the largest artery (the aorta) and ending in the small arterioles. Arteries are classified into 3 types: large elastic arteries, medium muscular arteries, and small arteries and arterioles. Arteries. Patients present with acute onset chest pain Pain Pain has accompanied humans since they first existed, first lamented as the curse of existence and later understood as an adaptive mechanism that ensures survival. Pain is the most common symptomatic complaint and the main reason why people seek medical care. Physiology of Pain. As in the case of myocarditis, heart failure can develop, which is usually accompanied by elevated troponins and typical ischemic ECG ECG An electrocardiogram (ECG) is a graphic representation of the electrical activity of the heart plotted against time. Adhesive electrodes are affixed to the skin surface allowing measurement of cardiac impulses from many angles. The ECG provides 3-dimensional information about the conduction system of the heart, the myocardium, and other cardiac structures. Normal Electrocardiogram (ECG) changes (ST elevations or depressions). Wall-motion abnormalities can be diagnosed based on a transthoracic echo. Management is with antiplatelet medications, nitrates Nitrates Nitrates are a class of medications that cause systemic vasodilation (veins > arteries) by smooth muscle relaxation. Nitrates are primarily indicated for the treatment of angina, where preferential venodilation causes pooling of blood, decreased preload, and ultimately decreased myocardial O2 demand. Nitrates, beta blockers, and revascularization.
  • Pericardial effusion Pericardial effusion Pericardial effusion is the accumulation of excess fluid in the pericardial space around the heart. The pericardium does not easily expand; thus, rapid fluid accumulation leads to increased pressure around the heart. The increase in pressure restricts cardiac filling, resulting in decreased cardiac output and cardiac tamponade. Pericardial Effusion and Cardiac Tamponade and tamponade: the presence of fluid in the pericardial sac, which can cause compression of the heart and lead to tamponade physiology. Tamponade physiology prevents the heart from filling and results in hemodynamic collapse. Beck’s triad of distended neck veins Veins Veins are tubular collections of cells, which transport deoxygenated blood and waste from the capillary beds back to the heart. Veins are classified into 3 types: small veins/venules, medium veins, and large veins. Each type contains 3 primary layers: tunica intima, tunica media, and tunica adventitia. Veins, hypotension Hypotension Hypotension is defined as low blood pressure, specifically < 90/60 mm Hg, and is most commonly a physiologic response. Hypotension may be mild, serious, or life threatening, depending on the cause. Hypotension, and muffled heart sounds Heart sounds Heart sounds are brief, transient sounds produced by valve opening and closure and by movement of blood in the heart. They are divided into systolic and diastolic sounds. In most cases, only the first (S1) and second (S2) heart sounds are heard. These are high-frequency sounds and arise from aortic and pulmonary valve closure (S1), as well as mitral and tricuspid valve closure (S2). Heart Sounds is often noted on physical exam. Diagnosis is confirmed using transthoracic echocardiography, and management involves drainage of the pericardium.
  • Pulmonary embolism: obstruction of the pulmonary arteries Arteries Arteries are tubular collections of cells that transport oxygenated blood and nutrients from the heart to the tissues of the body. The blood passes through the arteries in order of decreasing luminal diameter, starting in the largest artery (the aorta) and ending in the small arterioles. Arteries are classified into 3 types: large elastic arteries, medium muscular arteries, and small arteries and arterioles. Arteries, which is most often due to thrombus migration from the deep venous system. Signs and symptoms include pleuritic chest pain Pain Pain has accompanied humans since they first existed, first lamented as the curse of existence and later understood as an adaptive mechanism that ensures survival. Pain is the most common symptomatic complaint and the main reason why people seek medical care. Physiology of Pain, dyspnea, tachypnea, and tachycardia. Severe cases of pulmonary embolism Pulmonary Embolism Pulmonary embolism (PE) is a potentially fatal condition that occurs as a result of intraluminal obstruction of the main pulmonary artery or its branches. The causative factors include thrombi, air, amniotic fluid, and fat. In PE, gas exchange is impaired due to the decreased return of deoxygenated blood to the lungs. Pulmonary Embolism can result in hemodynamic instability or cardiopulmonary arrest. A chest CT with angiography is the primary method of diagnosis. Management includes oxygenation, and anticoagulant and thrombolytic therapies for unstable patients.

References

  1. Leone, O., Pieroni, M., Rapezzi, C., et al. (2019). The spectrum of myocarditis: From pathology to the clinics. Virchows Arch. 475, 279–301. https://doi.org/10.1007/s00428-019-02615-8
  2. Cooper, L.T. (2018). Etiology and pathogenesis of myocarditis. In Yeon, S.B. (Ed.), UpToDate. Retrieved March 19, 2021, from https://www.uptodate.com/contents/etiology-and-pathogenesis-of-myocarditis
  3. Cooper, L.T. (2021). Clinical manifestations and diagnosis of myocarditis in adults. In Dardas, T.F. (Ed.), UpToDate. Retrieved March 19, 2021, from https://www.uptodate.com/contents/clinical-manifestations-and-diagnosis-of-myocarditis-in-adults
  4. Hoit, B.D. (2020). Myocarditis. MSD Manual Professional Version. Retrieved March 30, 2021, from https://www.msdmanuals.com/professional/cardiovascular-disorders/myocarditis-and-pericarditis/myocarditis
  5. Al-Akchar, M., Kiel, J. (2020). Acute myocarditis. StatPearls. Retrieved March 30, 2021, from https://www.ncbi.nlm.nih.gov/books/NBK441847/
  6. Kang, M., An, J. (2020). Viral myocarditis. StatPearls. Retrieved March 30, 2021, from https://www.ncbi.nlm.nih.gov/books/NBK459259/
  7. Pandey, S., and Rajasurya, V. (2020). Nonviral myocarditis. StatPearls. Retrieved March 30, 2021, from https://www.ncbi.nlm.nih.gov/books/NBK536928/
  8. Tang, W.H. (2016). Myocarditis. In Ooi, H.H. (Ed.), Medscape. Retrieved March 30, 2021, from https://emedicine.medscape.com/article/156330-overview

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