Viral myocarditis is the disease that the heart is attacked by a virus and mainly with demonstration of myocarditis lesions. Its features can be summarized as "one big, one few, one fast." "One big" refers to the large disparity in the severity of disease state. Some children's symptoms are serious, but some children appear only ECG change, or only show slight palpitation, chest tightness, always sigh, fatigue, lazy to move, looking gray, etc. Others have even no symptoms. "One few" refers to the relatively homogeneous clinical symptom. For instance, some children with the performance of laziness to move, while the parents may consider it is caused by food acccumulation. However, parents should note that the incidence location of viral myocarditis partly is in the heart, so the children's disease condition may suddenly deteriorate and then appear cardiac insufficiency to threaten the life.