Supraventricular tachycardia (SVT) is an irregularly fast or erratic heartbeat that affects the heart’s upper chambers.

The mechanism by which adenosine reduces the incidence of SVTs, particularly atrioventricular nodal reentrant tachycardia (AVNRT) and atrioventricular reentrant tachycardia (AVRT), involves its effects on the AV node.




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