Myocarditis Management

Treatment Approach

The American College of Cardiology recommends treating myocarditis with supportive care focused on heart failure management, with immunosuppressive therapy reserved only for specific forms such as giant cell, cardiac sarcoidosis, or eosinophilic myocarditis 1
Patients presenting with dilated cardiomyopathy should be treated according to standard heart failure guidelines 1
Avoid NSAIDs due to risk of increased inflammation and mortality, with the exception of cases with suspected pericardial involvement 1
Avoid competitive sports and strenuous exercise for 3-6 months after diagnosis 1
Mechanical circulatory support (MCS) may be required for cardiogenic shock despite optimal medical management, and some patients can be bridged to recovery 1
Acute arrhythmia management is supportive, as arrhythmias often resolve with resolution of inflammation 1
For drug-refractory ventricular arrhythmias, endocardial and epicardial radiofrequency catheter ablation can be effective 1
Cardiac transplantation should be considered for patients with refractory heart failure, with similar survival rates after transplantation for adult patients with myocarditis as for other causes of cardiac failure 1

A diagnostic workup for myocarditis should include a 12-lead ECG, high-sensitivity cardiac troponin measurement, transthoracic echocardiogram, and inflammatory markers 2
Cardiac MRI is recommended in hemodynamically stable patients to confirm diagnosis and assess extent of myocardial involvement, according to the American College of Cardiology 3
Endomyocardial biopsy should be considered in patients with life-threatening disease course, failure to respond to supportive measures, or suspected giant cell myocarditis, as suggested by the European Heart Journal 2
Initial evaluation should include basic cardiac testing such as ECG, high-sensitivity cardiac troponin, echocardiogram, ambulatory rhythm monitoring, chest imaging, and pulmonary function tests when appropriate, as recommended by the American College of Cardiology 3

The role of immunosuppression in patients requiring mechanical circulatory support remains uncertain 1
Patients with myocarditis and fever require immediate hospitalization with cardiac monitoring, supportive care, and diagnostic evaluation to reduce mortality risk, as recommended by the European Society of Cardiology 2
The European Society of Cardiology recommends appropriate antimicrobial therapy for bacterial causes of myocarditis, such as Lyme disease or diphtheria 2
Corticosteroids are recommended for COVID-19 associated myocarditis, especially with concurrent pneumonia requiring oxygen, as suggested by the American College of Cardiology 3
Immunosuppressive therapy is indicated for giant cell myocarditis, cardiac sarcoidosis, or eosinophilic myocarditis 1

ACE inhibitors/ARBs should be maintained unless there is significant hemodynamic compromise, as recommended by the American College of Cardiology 4
Beta-blockers should be continued in hemodynamically stable patients, according to the American College of Cardiology 3
Low-dose aldosterone antagonists should be considered for patients with mildly reduced LV function, according to the American College of Cardiology 3 and the European Society of Cardiology 5
Diuretics should be adjusted based on fluid status assessment, with close weight monitoring to guide diuretic dosing and assess fluid status, as recommended by the American Heart Association, based on evidence from Circulation 6
Medications that may prolong QT interval should be avoided, as recommended by the European Society of Cardiology 2

Surveillance testing at 3-6 months, including ECG, echocardiogram, and cardiac MRI, is recommended, although the specific guidelines for this are not provided in the cited references
Complete abstinence from competitive sports and strenuous exercise for 3-6 months is advised, with return to activity only when all criteria are met: absence of symptoms, normalized cardiac function, and absence of arrhythmias, although this is not directly cited from a specific guideline society
Persistent AV blocks may develop and require permanent pacing, with device selection reflecting LV function, as suggested by the European Society of Cardiology 2
Follow-up is critical to gauge recovery of cardiac function and inflammation, guide heart failure management, and assess prognosis, as recommended by the American College of Cardiology 3
Return to activity criteria include absence of cardiopulmonary symptoms, resolution of laboratory evidence of myocardial injury, normalization of LV systolic function, and absence of spontaneous/inducible cardiac arrhythmias on ECG monitoring and exercise stress testing 3

Hospitalization may be necessary for monitoring and management if myocarditis is suspected, with consideration of cardiac MRI in appropriate cases, as recommended by the American College of Cardiology 3
Indications for hospitalization include hemodynamic instability, significant respiratory distress or hypoxemia, evidence of myocardial involvement, inability to maintain oral intake, worsening heart failure symptoms despite outpatient management, and severe viral illness requiring advanced care 3
Close monitoring of vital signs is necessary, with particular attention to heart rate, blood pressure, respiratory rate, and oxygen saturation, to quickly identify potential complications 3
Baseline laboratory tests, including complete blood count, renal function and electrolytes, cardiac biomarkers (troponin, BNP/NT-proBNP), and inflammatory markers (CRP, ESR), should be obtained to assess for myocardial involvement, as recommended by the American College of Cardiology and the American Academy of Family Physicians 3, 7