What is the morbidity and mortality of viral myocarditis in pediatric patients?

From the Guidelines

Viral myocarditis in children carries significant morbidity and mortality risks, with mortality rates ranging from 2-20% depending on severity, viral etiology, and timing of diagnosis, as reported in the most recent study from 2022 1. The disease can lead to severe complications, including heart failure, arrhythmias, and exercise intolerance. Factors associated with worse outcomes include younger age at presentation, fulminant presentation with shock, severely reduced ejection fraction (<30%), and delayed diagnosis. Some key points to consider in the management of viral myocarditis in children include:

• The use of supportive care, including heart failure management with diuretics, ACE inhibitors, and in severe cases, inotropic support, as recommended by the American Heart Association 1.
• The importance of early recognition through clinical symptoms, cardiac biomarkers (troponin, BNP), ECG changes, and echocardiography, as highlighted in the European Society of Cardiology guidelines 1.
• The potential need for prolonged ECG monitoring and hospital admission in patients with ventricular arrhythmias or heart block, as noted in the European Heart Journal study 1.
• The consideration of immunosuppressive therapy, such as intravenous immunoglobulin, in certain cases, although the evidence is limited and controversial, as discussed in the Circulation study 1. Overall, the management of viral myocarditis in children requires a comprehensive and multidisciplinary approach, taking into account the latest evidence and guidelines to improve outcomes and reduce morbidity and mortality. Key considerations in the diagnosis of myocarditis include:
• The use of endomyocardial biopsy as the diagnostic gold standard, although it is invasive and prone to sampling error, as noted in the Circulation study 1.
• The importance of clinical factors, such as patient history, symptoms, ECG changes, and serologic findings, in making a diagnosis, as highlighted in the European Society of Cardiology guidelines 1.

From the Research

Morbidity and Mortality of Viral Myocarditis in Children

• Viral myocarditis is a common pediatric illness that can lead to acquired heart failure, cardiomyopathy, and cardiac transplantation 2.
• The disease can cause devastating symptoms in otherwise healthy children, including respiratory distress and cardiovascular collapse 3.
• The morbidity and mortality of viral myocarditis in children can be significant, with severe cases presenting with symptoms such as fever, lethargy, congestive heart failure, cardiogenic shock, or new onset arrhythmias 4.

Clinical Presentation and Diagnosis

• The clinical presentation of viral myocarditis in children can be subtle, but if left untreated, it can lead to severe symptoms 4.
• The diagnosis of viral myocarditis is often unrecognized until later in the disease course, and it should be considered in the differential diagnosis of all children presenting with respiratory distress 2.
• Diagnostic studies, such as cardiac magnetic resonance imaging (CMR), can be useful in evaluating cardiac function and identifying the viral agent 2, 5.

Treatment and Management

• The treatment of viral myocarditis is mainly supportive, with a focus on hemodynamic stabilization, optimization of heart failure management, and supportive therapy 3, 6.
• The use of anti-inflammatory, immunosuppressing, and anti-viral therapy is debatable, and the role of these treatments is still being studied 2.
• Children with viral myocarditis often require admission to an intensive care setting, and the nursing care should focus on continual assessment of the cardiovascular system and supporting the recovery of myocardial function 4, 6.

Prognosis and Outcome

• The outcome of viral myocarditis in children is generally favorable, but delay in supportive care may be associated with a worse prognosis 2.
• The risk of sudden cardiac death (SCD) in patients with viral myocarditis is significant, especially in those with wide areas of late gadolinium enhancement (LGE) on CMR 5.
• The management of viral myocarditis should include a shared decision-making approach, taking into account the risk of SCD and the potential need for implantable cardioverter defibrillator (ICD) implantation 5.