[Risk factors for acute fulminant myocarditis in children]

To investigate the risk factors for fulminant myocarditis by analyzing clinical symptoms/signs or laboratory findings in children with viral myocarditis.

The medical data of 71 children with acute viral myocarditis from March 2005 to September 2008 were retrospectively studied. They were classified into fulminant (n=16) and non-fulminant myocarditis groups (n=55). Chi-square and Student's t-test were used to analyze the clinical presentations, laboratory data, EEG and cardiac ultrasound findings on admission. The multiple regression analysis was used to identify the independent risk factors for fulminant myocarditis.

Eight children (50%) died in the fulminant myocarditis group, but none in the non-fulminant group. The following factors were closely related to the fulminant course of myocarditis: lower blood pressure, higher serum CK-MB level, positive cTnI, complete atrioventricular block and left bundle branch block, ST segment alterations, prolonged QRS complex, and decreased left ventricular ejection fraction and short axis fractional shortening. Multiple regression analysis revealed that prolonged QRS complex (OR=1.139; CI=1.014-1.279, P<0.05) and decreased left ventricular ejection fraction (OR=0.711; CI=0.533-0.949, P<0.05) were independent risk factors for fulminant myocarditis.

The mortality of fulminant myocarditis is high in children. Prolonged QRS complex and decreased left ventricular ejection fraction on admission are independent risk factors for fulminant myocarditis in children.