The vast majority of children with pediatric myocarditis can be cured with proper and reasonable treatment and adequate rest. Some children have recurrent disease and may have sequelae, as follows: 1) weakness after exercise, chest tightness, breath-holding and other symptoms, which will be prolonged for more than 1 year and will enter the chronic phase, and children in the chronic phase will develop chronic cardiac insufficiency, and after a long period of years, dilated cardiomyopathy will appear and eventually die of heart failure; 2) some children will have various arrhythmias, such as atrial premature beats, ventricular premature beats, ventricular tachycardia Atrial tachycardia, atrial tachycardia; there may also be various conduction blocks, one degree block heart rate is no problem, in second and third degree block, the heartbeat will have missed beats and pauses, third degree atrioventricular block is the most serious, the heart rate is very slow, the heart rate is only 40-50 times, when the blood supply to the brain is insufficient, it will cause serious hypoxia, the child often fainting, or even sudden death. Therefore, it is important for children with myocarditis to be observed, followed up and checked regularly.