[Cardiac arrhythmias in childhood].

The knowledge of various dysrhythmias and their prognostic value permits the selection of appropriate diagnostic and management strategies. The most frequent pediatric dysrhythmias are described: premature atrial and ventricular contractions, supraventricular tachycardias, preexcitation syndrome, long Q-T syndrome, sick sinus syndrome, A-V blocks congenital and acquired. These arrhythmias may be related to structural abnormalities of the conduction system or may reflect temporary cardiac immaturity, as in the newborn, or may occur after surgical repair of a congenital cardiac lesion. It is important decide if the arrhythmias is benign and likely to resolve spontaneously or if it is potentially dangerous. Sometimes an arrhythmias indicates underlying extracardiac disease such as central nervous system disease, sepsis, hypoglycemia, drug toxicity, severe tissue hypoxia, electrolyte abnormalities. In these instances the treatment of the underlying cause will correct the rhythm abnormalities.