Atrioventricular reentrant tachycardia (AVRT) is a condition in which the electrical signals in the heart are disrupted, causing a rapid heartbeat. There are several synonyms for AVRT, including paroxysmal supraventricular tachycardia (PSVT), atrial tachycardia, atrioventricular nodal reentrant tachycardia (AVNRT), and Wolff-Parkinson-White (WPW) syndrome. PSVT is the most commonly used synonym for AVRT and refers to an episode of fast heart rate that begins in the upper chambers of the heart (atria). Atrial tachycardia is a type of PSVT that originates in the atria and causes a rapid heartbeat. AVNRT and WPW syndrome are less common synonyms for AVRT and refer to specific types of PSVT with different underlying causes.