Acute myocarditis in children: Current concepts and management

Abstract

The spectrum of presentation of pediatric myocarditis ranges from minor flu-like illness with chest pain to acute cardiogenic shock in a previously healthy child. A major change in the diagnostic evaluation of myocarditis is a shift in focus away from endomyocardial biopsy and histologic confirmation toward cardiac MRI for noninvasive diagnosis and prognostication of acute myocarditis. Cardiac MRI may be particularly useful in pediatric patients, considering the risks associated with biopsy in children. Some of the MRI characteristics seen in pediatric patients with acute myocarditis also may serve as predictors of outcome. The approach to managing myocarditis varies according to the severity of presentation; it is primarily supportive while spontaneous recovery of cardiac function is awaited. For subacute heart failure, the mainstay of therapy is still supportive management with oral heart failure medications such as angiotensin-converting enzyme inhibitors, beta-blockers, and diuretics. Acute myocarditis presenting with severe symptomatology, termed fulminant myocarditis, has a high recovery rate. Aggressive supportive care, including mechanical circulatory support, is indicated in fulminant myocarditis. With the increasing availability of and experience with paracorporeal pulsatile mechanical assist devices for children, more and more young patients are being bridged to transplantation or recovery. Despite promising results from several uncontrolled pediatric studies using immunosuppressive and/or immunomodulating therapy with intravenous gamma-globulin, the translation of these results into a recommended, routine therapy for pediatric myocarditis has been complicated by the high rate of spontaneous improvement of myocarditis with supportive care and the lack of demonstrable benefit for such therapies in blinded, randomized, placebo-controlled trials in adult myocarditis. Further clinical studies are necessary to define the possible utility of immunosuppressive, immunomodulatory, and antiviral therapy. Heart transplantation remains the final therapeutic option for children with myocarditis and intractable severe heart failure.

Predictors of Extracorporeal Membrane Oxygenation Support for Children with Acute Myocarditis

“…In our series, fever (68.3%), cough (56.7%), and chest pain (53.3%) were the major symptoms in children with acute myocarditis. However, in other studies, the most common symptoms were fever, shortness of breath, gastrointestinal symptoms, hypoperfusion, and poor feeding [5, 10, 18, 19]. Furthermore, our study population had a higher incidence of cardiac symptoms (chest pain and palpitation) than other studies did [5, 10, 18, 19].…”

Case Report: III° atrioventricular block due to fulminant myocarditis managed with non-invasive transcutaneous pacing

“…Among them only a few present with chest pain 10 . Diagnosis is mainly done on the basis of: Clinical presentation, blood profile, including CBC, electrolytes, creatinine kinase, creatine kinase MB isoenzyme, C-reactive protein, Troponin T, Troponin I, antistreptolysin O titer, polymerase chain reaction to detect viral antigens, autoantibodies marker, liver enzymes, ECG, Echocardiography, ultrasonography and even Cardiac MRI 3 which are mostly supportive. If echocardiography shows low LVEF in children with fulminant myocarditis, the prognosis is poor 11 .…”

“…There are about 10–38% cases of fulminant myocarditis among all cases of acute myocarditis 1 . Causes of fulminant myocarditis may be of viral, bacterial or non-infectious origin 1– 3 . Diagnosis of fulminant myocarditis is very difficult because of non-specific symptoms and diagnostic tools.…”

Myocarditis in Childhood: An Update on Etiology, Diagnosis and Management

“…In a retrospective study published in 2009, researchers found that myocarditis in children is characterized mainly by subepicardial and transmural enhancement. Global hypokinesia, left ventricular dilatation, ejection fraction less than 30% and transmural myocardial involvement were discovered to be associated with poor outcome (Vashist et al, 2009). …”

“…Although the long-term sequels are rare, dilated cardiomyopathy and sudden cardiac death may develop in clinical course. Extracorporeal membrane oxygenation and mechanical ventilations are other options for severe cases (Vashist & Singh, 2009). Newer therapeutic strategies such as intravenous immunoglobulin and immunosuppressive agents have been investigated with the improvements in understanding pathogenesis of the myocarditis (Drucker et al, 1994& Camargo et al 2009.…”