[Acute myocarditis in children. Study of 11 clinical cases]

The diagnosis of acute myocarditis in children is based on histological criteria. Often viral in origin, it results in acute left ventricular dysfunction, the clinical manifestations of which are very variable. The potential severity of the disease is maximal in its initial phase, justifying rapid and intensive treatment. Long-term outcome is relatively good although there is a risk of chronic left ventricular dysfunction. This retrospective study is based on 11 cases of acute myocarditis admitted to the paediatric unit of Clermont-Ferrand University Hospital between February 1989 and March 1999. The initial symptoms were non-specific. Echocardiography was the key diagnostic procedure. Half of the patients had severe cardiac failure requiring admission to the intensive care unit. Four cases presented with a severe complication: two embolic events, one syncopal atrioventricular block and one cardiac arrest. The cardiac treatment was classical (digitalis, diuretics, angiotensin converting enzyme inhibitors, anticoagulants). The aetiology was established in 3 cases (toxoplasmosis, haemolytic and uraemic syndrome, Kawasaki) and a viral cause was suspected in 6 other cases (adenovirus in 3 cases, herpes virus, RSV and enterovirus in 1 case). There were no deaths in the acute phase. The long-term outcome was globally good: complete regression in 8 cases, 1 chronic left ventricular dysfunction and 2 late deaths due to intractable cardiac failure. This short series illustrates the often misleading presentation of acute myocarditis in childhood, the value of systematic investigation in the hope of a specific treatment becoming available in the near future for the often viral aetiology.