It is a form of arrhythmia belonging to the group of supraventricular tachycardias. It is characterized by the presence of an increase in cardiac rhythm due to the presence of an ectopic (anomalous) site of origin of the electrical signal of the heart, which is not located in the sinoatrial node but in another location at the level of the atria (focal atrial tachycardias), or by an electrical impulse that turns in an anomalous manner (reentry circuit) inside the antra around some anatomical structures of the heart or areas of fibrosis of the atria, . (atrial reentry tachycardias) It is defined by a heart rate between 120 and 250 bpm and by an isoelectric interval between the various P waves. The electrocardiographic examination, if performed during the acute episode, allows both the diagnosis and the possibility of locating the ectopic focus with good sensitivity.

Focal atrial tachycardia is often characterized by the phenomenon of "warming", whereby the first cycles are relatively long and the subsequent ones gradually become shorter. This behavior is useful to distinguish focal tachycardia from that due to a reentry mechanism, in which warming is not a characteristic phenomenon. Reentry tachycardia, on the other hand, has a paroxysmal course, and is triggered by a single extrastimulus, often an atrial extrasystole, which does not occur for automatic tachycardias.

Medical treatment, based on the administration of antiarrhythmic drugs, has always guaranteed unsatisfactory results and the reference therapeutic protocol includes transcatheter ablation of the ectopic focus after mapping it, which represents the gold standard in the case of symptomatic patients. Ablative treatment allows a better prognosis in the long term with a low incidence of complications.