New concepts in myocarditis

Myocarditis in Paediatric Patients: Unveiling the Progression to Dilated Cardiomyopathy and Heart Failure

Myocarditis is a challenging and potentially life-threatening disease associated with high morbidity in some paediatric patients, due to its ability to present as an acute and fulminant disease and to ultimately progress to dilated cardiomyopathy. It has been described as an inflammatory disease of the myocardium caused by diverse aetiologies. Viral infection is the most frequent cause of myocarditis in developed countries, but bacterial and protozoal infections or drug hypersensitivity may also be causative agents. The prompt diagnosis in paediatric patients is difficult, as the spectrum of clinical manifestation can range from no myocardial dysfunction to sudden cardiac death. Recent studies on myocarditis pathogenesis have revealed a triphasic nature of this disease, which influences the diagnostic and therapeutic strategies to adopt in each patient. Endomyocardial biopsy remains the gold standard for diagnosing myocarditis, and several non-invasive diagnostic tools can be used to support the diagnosis. Intravenous immunoglobulin has become part of routine practice in the treatment of myocarditis in paediatric patients at many centres, but its true effect on the cardiac function has been the target of many studies. The aim of this review is to approach the recently discovered facets of paediatric myocarditis regarding its progression to dilated cardiomyopathy.

Myocarditis and pericarditis in children

Myocarditis and pericarditis are rare but important causes of pediatric chest pain. The diagnostic criteria, clinical course, causes, and treatment of myocarditis is reviewed. There is particular attention to the relationship of myocarditis with dilated cardiomyopathy. Supportive therapy remains the standard of care for pump dysfunction. The identification and treatment of pericarditis with associated large pericardial effusion can be lifesaving. This article reviews the important clinical features that might lead the clinician to diagnose either myocarditis or pericarditis and thus separate the few patients with either of these conditions from the legions of children with noncardiac chest pain.