Home Diseases and Health Information  

Home Home Translating Report News Physicians Diseases Body Sites Diseases and Health Information Search


Myocarditis is a direct inflammation of the heart musculature. Infections are the most common cause. Patients present with a variety of symptoms from asymptomatic to an acute onset of heart failure.


Disease Associations  
Other Diagnostic Testing
Gross Appearance and Clinical Variants  
Histopathological Features and Variants  
Special Stains/
Electron Microscopy
Differential Diagnosis  
Commonly Used Terms  
Internet Links  



Celiac disease associated with autoimmune myocarditis.

Frustaci A, Cuoco L, Chimenti C, Pieroni M, Fioravanti G, Gentiloni N, Maseri A, Gasbarrini G.

Department of Cardiology, Catholic University, Rome, Italy.

Circulation 2002 Jun 4;105(22):2611-8 Abstract quote

BACKGROUND: Both celiac disease (CD) and myocarditis can be associated with systemic autoimmune disorders; however, the coexistence of the 2 entities has never been investigated, although its identification may have a clinical impact.

METHODS AND RESULTS: We screened the serum of 187 consecutive patients with myocarditis (118 males and 69 females, mean age 41.7+/-14.3 years) for the presence of cardiac autoantibodies, anti-tissue transglutaminase (IgA-tTG), and anti-endomysial antibodies (AEAs). IgA-tTG-positive and AEA-positive patients underwent duodenal endoscopy and biopsy and HLA analysis. Thirteen of the 187 patients were positive for IgA-tTG, and 9 (4.4%) of them were positive for AEA. These 9 patients had iron-deficient anemia and exhibited duodenal endoscopic and histological evidence of CD. CD was observed in 1 (0.3%) of 306 normal controls (P<0.003). In CD patients, myocarditis was associated with heart failure in 5 patients and with ventricular arrhythmias (Lown class III-IVa) in 4 patients. From histological examination, a lymphocytic infiltrate was determined to be present in 8 patients, and giant cell myocarditis was found in 1 patient; circulating cardiac autoantibodies were positive and myocardial viral genomes were negative in all patients. HLA of the patients with CD and myocarditis was DQ2-DR3 in 8 patients and DQ2-DR5(11)/DR7 in 1 patient. The 5 patients with myocarditis and heart failure received immunosuppression and a gluten-free diet, which elicited recovery of cardiac volumes and function. The 4 patients with arrhythmia, after being put on a gluten-free diet alone, showed improvement in the arrhythmia (Lown class I).

CONCLUSIONS: A common autoimmune process toward antigenic components of the myocardium and small bowel can be found in >4% of the patients with myocarditis. In these patients, immunosuppression and a gluten-free diet can be effective therapeutic options.

Association of drowning and myocarditis in a pediatric population: an autopsy-based study.

Somers GR, Smith CR, Wilson GJ, Zielenska M, Tellier R, Taylor GP.

Division of Pathology, Department of Pediatric Laboratory Medicine, Hospital for Sick Children, Toronto, Ontario, Canada
Arch Pathol Lab Med. 2005 Feb;129(2):205-9. Abstract quote

CONTEXT: Drowning is a frequent cause of accidental death in childhood, but the association of myocarditis and drowning has only rarely been reported.

OBJECTIVE: To report 5 cases of drowning in children with coexistent myocarditis.

DESIGN: A retrospective review of autopsy records of patients 0 years to 18 years of age was performed during a 6-year period (1998-2003, total cases reviewed = 1431).

RESULTS: Twenty-two drownings were identified, in 14 male and 8 female children. Five patients (23%), 3 female and 2 male children, had coexistent myocarditis. The 5 patients ranged in age from 23 months to 13 years (mean, 7 years 2 months). None of the patients had antecedent symptomatology suggestive of myocarditis. In all patients, the myocarditis was focal mild or moderate, and the inflammatory infiltrate comprised lymphocytes with smaller numbers of neutrophils. All 5 patients had foci of myocyte necrosis. One patient had histologic evidence of myocardial hypertrophy but no evidence of a cardiomyopathy. Microbiologic studies, including culture, immunohistochemistry, polymerase chain reaction, and reverse transcriptase polymerase chain reaction, revealed Mycoplasma pneumoniae DNA in 1 case.

CONCLUSIONS: The finding of myocarditis in a significant proportion of drowning victims in this series highlights the importance of a thorough autopsy examination in apparently straightforward cases and has clinicopathologic significance.

Poststreptococcal (rheumatic fever)
Drug hypersensitivity (Doxorubicin, cyclophosphamide)
Transplant rejection

INFECTIONS Viruses (coxsackievirus, ECHO, influenza, HIV, CMV)
Bacteria (Corynebacterium diphtheria, Neisseria meningococcus, Borrelia Lyme disease)
Protozoa (Trypanosoma cruzi, Chagas diseas, Toxoplasmosis)
UNKNOWN Sarcoidosis
Giant cell myocarditis
TOXINS Cocaine

Chronic Active Myocarditis Following Acute Bartonella henselae Infection (Cat Scratch Disease)

Glenn R. Meininger, M.D.; Tibor Nadasdy, M.D.; Ralph H. Hruban, M.D.; Robert C. Bollinger, M.D.; Kenneth L. Baughman, M.D.; Joshua M. Hare, M.D.

From the Departments of Medicine, Division of Cardiology (G.R.M., K.L.B., J.M.H.), Division of Infectious Diseases (R.C.B.), and the Department of Pathology (T.N., R.H.H.), Johns Hopkins Hospital, Baltimore, Maryland, U.S.A.

Am J Surg Pathol 2001;25:1211-1214 Abstract quote

An association between Bartonella infection and myocardial inflammation has not been previously reported.

We document a case of a healthy young man who developed chronic active myocarditis after infection with Bartonella henselae (cat scratch disease). He progressed to severe heart failure and underwent orthotopic heart transplantation.

Bartonella henselae, therefore, should be included among the list of infectious agents associated with chronic active myocarditis.


Prevalence of the parvovirus B19 genome in endomyocardial biopsy specimens.

Pankuweit S, Moll R, Baandrup U, Portig I, Hufnagel G, Maisch B.


Hum Pathol. 2003 May;34(5):497-503 Abstract quote

Although enteroviruses have long been considered the most common cause of inflammatory heart muscle diseases, parvovirus B19 (PVB19) is emerging as a new and important candidate for myocarditis and dilated cardiomyopathy with inflammation (DCMi) and without inflammation (DCM).

We investigated left ventricular endomyocardial biopsy specimens from 110 patients with suspected inflammatory heart disease for the presence of PVB19, Coxsackie virus (CVB), and adenovirus (Ad2) genome by polymerase chain reaction. Diagnosis of myocarditis (36 patients), DCM (18 patients), DCMi (13 patients), and perimyocarditis (12 patients) was made by immunohistochemical and histopathological investigation of endomyocardial biopsy specimens. A control group consisting of patients with arterial hypertension was also investigated. Prevalence of the PVB19 genome in endomyocardial biopsy specimens was highest in patients with DCMi (3 of 13) and patients with myocarditis (7 of 36); in patients with DCM and perimyocarditis, prevalence was 3 of 13 and 2 of 12, respectively.

In patients with resolved myocarditis, no PVB19 DNA was detected; in patients with no inflammation and controls, prevalence was only 4% and 7%, respectively. CVB-RNA was detected in endomyocardial biopsy specimens from 3 of 37 patients with myocarditis; Ad2-DNA was found in 1 patient with DCM and 1 patient with perimyocarditis.

These findings suggest an association of the PVB19 genome in endomyocardial biopsy specimens of adults with the development of DCM, DCMi, and chronic myocarditis more frequently than previously expected. PVB19 should therefore be recognized as a potential cardiotropic pathogen in patients of all ages.


Overexpression of tumor necrosis factor (TNF)alpha and TNFalpha receptor I in human viral myocarditis: clinicopathologic correlations.

Calabrese F, Carturan E, Chimenti C, Pieroni M, Agostini C, Angelini A, Crosato M, Valente M, Boffa GM, Frustaci A, Thiene G.

Department of Pathological Anatomy, University of Padua Medical School, Padua, Italy.

Mod Pathol. 2004 Sep;17(9):1108-18. Abstract quote

Proinflammatory cytokines, including tumor necrosis factor (TNF)alpha, have been recognized as important physiopathogenetic factors in the initiation and continuation of inflammatory cardiomyopathies. Experimental and preliminary human studies have demonstrated that TNFalpha plays a crucial role in enteroviral-induced myocarditis.

In this study, we investigated the expression of TNFalpha and both its receptors (TNFRI and TNFRII) in both viral and nonviral myocarditis. Myocardial expression of TNFalpha was then correlated with different clinical and pathologic findings. TNFalpha expression was investigated in endomyocardial biopsies obtained from 38 patients with myocarditis and from eight control subjects by using reverse transcriptase-polymerase chain reaction (PCR) and immunohistochemistry. Viral etiology was diagnosed by PCR in 20 cases: enterovirus in seven, Epstein-Barr virus in four, hepatitis C virus in three, adenovirus in two, influenza virus in two, cytomegalovirus in one, and double infection adenovirus and enterovirus in one. Immunohistochemistry was also used to analyze both TNFalpha receptors (RI and RII). A semiquantitative analysis was employed (score 0-3) for necrosis, inflammation, fibrosis and immunohistochemical findings. TNFalpha mRNA and TNFalpha protein were significantly more present in viral myocarditis than in nonviral myocarditis (16/20 vs 3/18, P=0.001). Remarkable immunostaining was observed for both receptors, particularly TNFRI. Histological analysis revealed that myocardial necrosis (mean score 1.89 vs 1.15, P=0.01) and cellular infiltration (mean score 2.26 vs 1.78, P=0.05) were more prominent in TNFalpha-positive cases. Among TNFalpha-positive cases, the greater TNFalpha mRNAs, the more impaired was cardiac function.

Our findings suggest that the expression of TNFalpha may play an important role in the pathogenesis of viral myocarditis of any etiology and may influence the severity of cardiac dysfunction. Cytokine effects are more strictly linked to overexpression of TNFRI.

Histologic and in situ viral findings in the myocardium in cases of sudden, unexpected death.

Cioc AM, Nuovo GJ.

Department of PathologyOhio State University Medical Center, Columbus, Ohio.

Mod Pathol 2002 Sep;15(9):914-22 Abstract quote

The purpose of this study was to do in situ viral detection in myocardial tissues of individuals who suffered sudden unexpected death and to correlate the results with the postmortem histopathologic findings.

Thirteen cases were identified and the heart tissues were analyzed for adenovirus, cytomegalovirus, Epstein Barr virus, herpes simplex virus 1 and 2, human immunodeficiency virus 1 (HIV-1), influenza A, influenza B, parvovirus, rotavirus, picornavirus (including separate primers for enterovirus and Coxsackie virus A and B), varicella zoster virus, and respiratory syncytial virus. Thirteen individuals aged 2 to 67 years were studied. In each case, polymerase chain reaction-amplified viral RNA was detected in situ: Coxsackie virus B (5 cases), rotavirus (4 cases), HIV-1 (2 cases), influenza A (1 case), and influenza B (1 case).

Immunohistochemical detection of viral proteins was found in the five Coxsackie virus cases and four rotavirus cases. The mononuclear inflammatory infiltrate was diffuse and marked only in the cases of influenza A and HIV-1, as well as one of the Coxsackie virus and rotavirus cases, respectively. Immunohistochemical analysis showed that the most common cell type in the inflammatory infiltrates was CD68-positive macrophages. Direct myocyte infection was most prominent in the cases of Coxsackie virus infection. In summary, in situ viral detection was documented in each case of idiopathic myocarditis associated with sudden, unexpected death; in 6/13 cases, the myocarditis was focal and minimal.

Although Coxsackie virus was, as expected, the most common virus noted, other viruses including rotavirus and HIV-1 were also observed, highlighting the need for comprehensive viral and histologic analyses in such cases.


Histopathologic, immunohistochemical, and polymerase chain reaction assays in the study of cases with fatal sporadic myocarditis.

Infectious Disease Pathology Branch, Centers for Disease Control and Prevention, Atlanta, GA 30333, USA.


Hum Pathol. 2007 Sep;38(9):1412-9. Abstract quot

Paraffin tissue blocks from 27 cases with sporadic myocarditis were collected during a 12-year period at a single medical examiner's office. Blocks were studied by using histopathology; immunohistochemistry for viruses (adenovirus, enterovirus, influenza A and B, and human herpes types 4 and 5), bacteria (Neisseria menigitidis, Ehlichia sp, spotted fever group Rickettsia) and parasites (Toxoplasma gondii and Trypanosoma cruzi); and polymerase chain reaction (PCR)/RT-PCR for adenovirus and enterovirus.

We identified enterovirus in 5 (18.5%) cases and Sarcocystis in a 36-year-old woman who had focal inflammation and myocyte necrosis. Immunohistochemical evidence of enteroviruses was found in the myocytes of 2 patients less than 6 months old who had diffuse mononuclear myocardial inflammation, interstitial pneumonitis; one also had encephalitis. In these 2 patients, the presence of enterovirus was confirmed by RT-PCR targeting the 5' nontranslated region and was serotyped as coxsackievirus B2 by sequencing the VP1 capsid region. In another 3 cases (ages 12, 47, and 54), enterovirus was detected by the 5' nontranslated region region; VP1 sequencing identified these as echoviruses 6, 13, and 7, respectively.

Accurately identifying an infectious agent is the foundation for clinical and public health interventions. Despite using multiple diagnostic methods, an organism could only be detected in a small proportion of sporadic myocarditis cases.
Diagnosis and presentation of fatal myocarditis.

Kyto V, Saukko P, Lignitz E, Schwesinger G, Henn V, Saraste A, Voipio-Pulkki LM.

Department of Anatomy, Institute of Biomedicine, University of Turku, 20520 Turku, Finland.

Hum Pathol. 2005 Sep;36(9):1003-7. Abstract quote  

The clinical presentation of myocarditis is highly variable, and histopathology is thus considered to be the cornerstone of diagnosis.

We studied how accurately myocarditis was diagnosed in a series of routine autopsies and how fatal myocarditis presents clinically. All death certificates with myocarditis recorded as the underlying cause of death in Finland in 1970 to 1998 were collected retrospectively (N = 639). All cases with cardiac autopsy samples and clinical data available (n = 142; median age, 51 years) were included in this study. The cardiac samples were reexamined for the presence of myocarditis by 3 experienced independent pathologists using the Dallas criteria. The clinical data were evaluated for the presenting signs and symptoms of myocarditis. Histopathologic reanalysis showed that only 32% of the 142 subjects met the Dallas criteria for myocarditis (75% of pediatric and 28% of adult patients, P = .001). Clinicians had suspected myocarditis in only one third of the hospitalized Dallas-positive patients. Dallas-positive patients presented more often with features of myocardial infarction (26% versus 9%, P = .026) or heart failure (35% versus 10%, P = .001) than Dallas-negative subjects. The signs and symptoms of infectious disease were also more common in Dallas-positive patients (61% versus 23%, P < .001). In contrast, Dallas-negative subjects died suddenly or were found dead more frequently (68% versus 39%, P = .004). The most evident cause of death in the Dallas-negative subjects was ischemic heart disease (n = 78, 55% of all cases).

Our study provides evidence that myocarditis is overdiagnosed on routine autopsies, particularly in patients who have died suddenly or are found dead. Fatal myocarditis appears to present equally often as heart failure, sudden death, or mimicking myocardial infarction.

General Active phase has interstitial infiltrate of usually mononuclear cells associated with focal myocyte necrosis
Hypersensitivity myocarditis Interstitial infiltrates and perivascular with lymphocytes, macrophages, and eosinophils
Giant cell myocarditis

Widespread inflammatory infiltrate with multinucleate giant cells with lymphocytes, eosinophils, plasma cells and macrophages

Focal but extensive necrosis

Macpherson and Pincus. Clinical Diagnosis and Management by Laboratory Methods. Twentyfirst Edition. WB Saunders. 2006.
Rosai J. Ackerman's Surgical Pathology. Ninth Edition. Mosby 2004.
Sternberg S. Diagnostic Surgical Pathology. Fourth Edition. Lipincott Williams and Wilkins 2004.
Robbins Pathologic Basis of Disease. Seventh Edition. WB Saunders 2005.
DeMay RM. The Art and Science of Cytopathology. Volume 1 and 2. ASCP Press. 1996.
Weedon D. Weedon's Skin Pathology Second Edition. Churchill Livingstone. 2002
Fitzpatrick's Dermatology in General Medicine. 6th Edition. McGraw-Hill. 2003.
Weiss SW and Goldblum JR. Enzinger and Weiss's Soft Tissue Tumors. Fourth Edition. Mosby 2001.

Commonly Used Terms

Basic Principles of Disease
Learn the basic disease classifications of cancers, infections, and inflammation

Commonly Used Terms
This is a glossary of terms often found in a pathology report.

Diagnostic Process
Learn how a pathologist makes a diagnosis using a microscope

Surgical Pathology Report
Examine an actual biopsy report to understand what each section means

Special Stains
Understand the tools the pathologist utilizes to aid in the diagnosis

How Accurate is My Report?
Pathologists actively oversee every area of the laboratory to ensure your report is accurate

Got Path?
Recent teaching cases and lectures presented in conferences

Internet Links

Last Updated September 18, 2007

Send mail to The Doctor's Doctor with questions or comments about this web site.
Read the Medical Disclaimer.

Copyright © The Doctor's Doctor