How is AV nodal reentrant tachycardia (AVRT) identified on an EKG?

AV nodal reentrant tachycardia (AVRT) is characterized by a rapid heart rate that generally falls within the range of 150-250 beats per minute. On an EKG, this presents as rapid, narrow QRS complexes with a regular rhythm. This is due to the reentry circuit that occurs within the atrioventricular node, which utilizes both the slow and fast pathways leading to a quick succession of impulses, thereby maintaining a narrow QRS complex as the electrical impulses travel rapidly through the His-Purkinje system.

The regular rhythm is also a signature feature of AVRT, distinguishing it from other tachycardias that may present with irregular rhythms, such as atrial fibrillation or multifocal atrial tachycardia. The regularity accompanies the fast rate and narrow QRS complexes consistently seen in this arrhythmia type.

This characteristic pattern helps clinicians distinguish AVRT from other types of tachycardia on an EKG, making it essential for diagnosis and appropriate management.