[Acute infectious myocarditis in children. Apropos of 2 series from Lyon].

Acute infectious myocarditis in childhood has a very poor initial outcome, but the long-term outlook is relatively good for the survivors. This retrospective study was based on cases of acute myocarditis admitted to two hospital departments with different modes of recruitment. Firstly, a polyvalent paediatric intensive care unit where 12 children (mean age 12 months) were admitted during the acute phase of myocarditis. The initial symptoms were non-specific and misleading, the diagnosis being established at autopsy in 9 cases. Only 4 children presented with typical cardiac failure. The clinical signs were hepatomegaly, sinus tachycardia, cardiomegaly, ECG ST-T wave changes and biological signs of multiple organ failure. Left ventricular function was very poor with a fractional shortening of only 17%. The causal agent was usually viral. The clinical course was marked by a high early mortality (11/26, 42%) within 23 hours of hospital admission. Secondly, a paediatric cardiology unit where 81 children (mean age 15 months) were followed up after acute infectious myocarditis. Thirteen cases were taken from our first series and were included for long-term follow-up; 76.5% had premonitory signs of infection and 71% were in cardiac failure, Classes III or IV, during the hospital admission. The causal agent was identified in 30 cases (37%) and was usually a virus (22 cases). Treatment was classical (association of digitalis, diuretics, angiotensin converting enzyme inhibitors, anticoagulants and beta-sympathomimetics when necessary).(ABSTRACT TRUNCATED AT 250 WORDS)