From the Guidelines
The recommended approach for an infection workup in myocarditis involves initial testing with an ECG, measurement of cTn, and an echocardiogram, followed by cardiology consultation and further testing with CMR if myocarditis is suspected. This approach is based on the most recent guidelines from the American College of Cardiology, which emphasize the importance of early diagnosis and treatment of myocarditis, particularly in the context of COVID-19 infection or vaccination 1.
When evaluating a patient with suspected myocarditis, it is essential to consider the clinical presentation, epidemiology, and exposure history to tailor the diagnostic workup and optimize treatment decisions. The workup should include:
- Blood cultures and viral serologies to identify common cardiotropic pathogens
- PCR testing for enteroviruses, adenoviruses, parvovirus B19, human herpesvirus 6, and cytomegalovirus
- Complete blood count, comprehensive metabolic panel, cardiac biomarkers (troponin and BNP), and inflammatory markers (ESR, CRP)
- Respiratory samples for respiratory viruses if symptoms suggest their involvement
- Endomyocardial biopsy may be considered in cases of unexplained heart failure, particularly when specific therapy would change based on findings 1.
In patients with suspected or confirmed COVID-19 myocarditis, treatment with corticosteroids may be considered, particularly in those with hemodynamic compromise or multisystem inflammatory syndrome (MIS-A) 1. The use of nonsteroidal anti-inflammatory drugs, colchicine, and corticosteroids should be considered in those with ongoing symptoms, and guideline-directed medical therapy for heart failure should be initiated and continued after discharge 1.
Overall, a systematic and tailored approach to the infection workup in myocarditis is crucial to guide targeted therapy and improve patient outcomes, with a focus on reducing morbidity, mortality, and improving quality of life.
From the Research
Infection Workup for Myocarditis
The recommended approach for an infection workup in myocarditis involves several steps:
- Identifying the cause of myocarditis, which can be viral, autoimmune, or due to other factors 2
- Using diagnostic tools such as electrocardiogram, echocardiogram, and cardiac magnetic resonance imaging to assess cardiac function and detect signs of inflammation 3, 4
- Measuring biomarkers such as troponins to detect cardiac damage 2
- Considering endomyocardial biopsy for definitive diagnosis, especially in cases of giant cell myocarditis or deteriorating patients 4
Common Causes of Myocarditis
The most common causes of myocarditis include:
- Viral infections, such as influenza and coronavirus 3, 2
- Systemic autoimmune disorders, such as systemic lupus erythematosus 2
- Drugs, such as immune checkpoint inhibitors 2
- Vaccines, including smallpox and mRNA COVID-19 vaccines 2
Diagnostic Approach
The diagnostic approach to myocarditis involves:
- Clinical evaluation, including presenting symptoms and medical history 2, 4
- Laboratory tests, including biomarkers and viral studies 3, 4
- Imaging studies, including electrocardiogram, echocardiogram, and cardiac magnetic resonance imaging 3, 4
- Endomyocardial biopsy, if necessary, to confirm diagnosis and guide treatment 4
Treatment and Management
Treatment and management of myocarditis depend on the underlying cause and severity of the disease:
- Supportive care, including rest and medical therapy, is often the primary approach 2, 5
- Immunosuppression, such as corticosteroids, may be used in specific cases, such as eosinophilic or giant cell myocarditis 2, 4
- Exercise restrictions may be recommended for a period of time, typically 3 to 6 months, to allow for recovery 5