Atrioventricular Node Reentry Supraventricular Tachycardia Differential Diagnoses

Updated: Dec 09, 2020
  • Author: Glenn T Wetzel, MD, PhD; Chief Editor: Stuart Berger, MD  more...
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DDx

Diagnostic Considerations

The permanent form of junctional reciprocating tachycardia (PJRT) is difficult to distinguish from atypical (fast-slow) atrioventricular node reentrant tachycardia (AVNRT). [11, 12, 13]  However, the response to premature atrial complexes (PACs) allows for differentiation between these two arrhythmias: His refractory PACs (HrPACs) perturbing the next His (resetting with fusion) is diagnostic of AVRNT; a late PAC that fuses with the native beat is not able to reset the focal source of junctional tachycardia. [13] However, simultaneous conduction through the AV nodal fast and slow pathways (ie, two-for-one response [TFOR]) can occur in both AVNRT and junctional tachycardia and, therefore, early PAC advancing the immediate His with continuation of tachycardia is not diagnostic of junctional tachycardia. [13]

Another rare mechanism is verapamil-sensitive atrial tachycardia originating from near the atrioventricular node. [14]

Differential Diagnoses