Myocarditis Presentation and Diagnosis in Adolescents

Clinical Presentation

The American Heart Association recognizes that myocarditis can present with signs of left- and/or right-sided heart failure in adolescents, with symptoms such as new-onset dyspnea, fatigue, or chest pain 1, 2, 3
Myocarditis in young patients can also present with arrhythmias, syncope, or sudden cardiac death as presenting features 1, 2
Acute fulminant presentations with cardiogenic shock can occur, particularly in younger patients 4

The American Heart Association recommends that the evaluation of myocarditis should proceed systematically, including initial assessment with ECG abnormalities, elevated cardiac troponin, and inflammatory markers 1, 2, 3
Echocardiography is recommended to assess RV size, function, wall motion abnormalities, pericardial effusion, and septal shift 1, 2, 3
Cardiac MRI is the preferred modality in hemodynamically stable patients, showing edema on T2-weighted imaging and late gadolinium enhancement in characteristic myocarditic patterns 1, 2, 7, 4

The American Academy of Pediatrics and the American Heart Association note that viral etiologies predominate in pediatric and adolescent myocarditis, with enteroviruses, adenovirus, and parvovirus B19 being common causes 1, 3
Younger patients (<1 year) have worse outcomes than older children and adolescents, according to the American Heart Association 8
Fulminant presentations are more common in young males with viral myocarditis, as reported by the Journal of the American College of Cardiology 7, 4

The American College of Cardiology recommends hemodynamic support with standard heart failure therapy (diuretics, ACE inhibitors, beta-blockers as tolerated) for the treatment of myocarditis 2, 6
Immunosuppression may be beneficial in specific etiologies, such as giant cell myocarditis, eosinophilic myocarditis, and cardiac sarcoidosis, according to the Journal of the American College of Cardiology 9, 2