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[Supraventricular tachycardia in children].

Supraventricular tachycardia is one of the most frequent arrhythmias in childhood. It may accompany congenital heart disease. W.P. W. syndrome, or a normal state of health. A re-entry circuit is the most commonly observed electrophysiological mechanism. Persistence is followed by decompensation. Drug management is based on digitalis, ATP, amiodarone, and verapamil. Atrial and ventricular pacing and surgery are alternatives when other means fail. Persistent tachycardia (i.e. its presence over long periods) is much less frequent that the paroxysmal form, and its aetiology is generally unknown. Even here, the clinical picture is substantially related to decompensation. Digitalis + amiodarone is the best treatment, though the arrhythmia may resolve spontaneously.