| Feature | Details |
|---|---|
Mechanisms | infection-related inflammation may result from direct infection of the myocardium or from circulating toxins. |
Most common causes | viral infections are the most common causes of myocarditis. |
Reported frequencies | Coxsackie infection is associated with 35 cases per 1000 infections, and influenza A and B with 25 cases per 1000 infections. |
Viral causes listed | Coxsackie, adenovirus, influenza A and B, human immunodeficiency virus, SARS-CoV-2 and dengue virus. |
Timing | myocarditis may occur several weeks after the initial viral symptoms. |
Increased susceptibility | glucocorticoid treatment, immunosuppression, radiation, previous myocardial damage and exercise increase susceptibility. |
| Feature | Details |
|---|---|
Bacterial causes | Borrelia burgdorferi and Mycoplasma pneumoniae are listed. |
Lyme disease | approximately 5% of patients develop myopericarditis, often associated with atrioventricular block. |
Protozoal causes | Trypanosoma cruzi, associated with Chagas disease, and Toxoplasma gondii are listed. |
Fungal cause | Aspergillus is listed. |
| Feature | Details |
|---|---|
Direct myocardial injury | alcohol, cocaine, lithium and doxorubicin may directly injure the myocardium. |
Additional listed drugs | anthracyclines, clozapine and immune checkpoint inhibitors are included among drug or toxin causes. |
Hypersensitivity | penicillins, sulphonamides, lead and carbon monoxide may cause a hypersensitivity reaction with associated myocarditis. |
Vaccines | SARS-CoV-2 vaccines can rarely cause myocarditis, which is commoner in young men. |