Set of tachycardias that originate above the bifurcation of the bundle of His and require the atrium, the AV node, or both for their initiation or persistence (AHA 2015 [1] and ESC 2019

[2]).

The name is based on the location, the circuit used and the pathophysiological mechanism of the arrhythmia (see super diagrams [3]). Atrial tachycardias (atrial fibrillation, flutter and TAF) are more frequent than atrioventricular arrhythmias (e.g. intranodal reentry tachycardias or AV reentry tachycardias via an accessory bundle). The latter are paroxysmal (with an initial onset and abrupt end mode), occur in younger patients with healthy hearts and their rates are faster.

The term "SVT" (supraventricular tachycardia) is used in everyday language in the presence of a regular tachycardia whose precise identification is difficult on one or more consecutive tracings and when there is a desire to rule out sinus tachycardia, atrial fibrillation or ventricular tachycardia.

It therefore includes, in this case, regular TSV with narrow but also wide QRS, that is to say essentially atrioventricular arrhythmias, focal AT and atrial flutter. The prevalence of paroxysmal TSV in the general population is poorly known [2].