Management of Post-Viral Myocarditis

General Principles

The American Heart Association states that immunosuppression is not indicated for the management of acute lymphocytic myocarditis in adults, based on individual trials and meta-analysis data 1, 3, 4
The European Society of Cardiology recommends against corticosteroid therapy in viral pericarditis (Class III, Level C), as steroids can reactivate many viral infections and lead to ongoing inflammation 2, 5

Corticosteroids can reactivate viral infections, perpetuating the inflammatory cascade rather than resolving it 2, 5
The use of corticosteroids does not reduce mortality in post-viral myocarditis, with a Cochrane systematic review finding no significant reduction in mortality (RR 0.93, 95% CI 0.70-1.24) 1
NSAIDs and corticosteroids may increase inflammation and mortality in isolated myocarditis without pericardial involvement 1, 3

Immunosuppression should be considered in non-viral forms of myocarditis, such as giant cell myocarditis, cardiac sarcoidosis, or eosinophilic myocarditis 1, 3, 4
Empiric corticosteroids may be considered in fulminant myocarditis with biopsy evidence of severe myocardial inflammatory infiltrates or in patients with hemodynamic compromise 3, 4
High-dose corticosteroids should be initiated promptly in suspected or confirmed immune checkpoint inhibitor-associated myocarditis 6, 7

Guideline-directed medical therapy for heart failure (ACE inhibitors/ARBs, beta-blockers if hemodynamically stable, aldosterone antagonists) should be used instead of steroids 1, 3, 4
Supportive care with hemodynamic monitoring and arrhythmia management is recommended 1, 3
Activity restriction for 3-6 months is advised, as sustained aerobic exercise during acute viral myocarditis can lead to increased mortality and sudden death 1, 3, 4
Mechanical circulatory support should be considered if cardiogenic shock develops despite optimal medical management 1, 3, 4