Validation of dual atrioventricular nodal physiology in dual atrioventricular nodal non‐reentrant tachycardia via adenosine triphosphate injection during atrial pacing: A novel insight into the role of leftward inferior extension.

Introduction: Dual atrioventricular nodal non‐reentrant tachycardia (DAVNNT) is a rare and challenging‐to‐diagnose arrhythmia, without previous reports associating it with a leftward inferior extension (LIE). Methods: Diagnosis was made using adenosine triphosphate (ATP) injection during atrial pacing in a suspected DAVNNT patient. Results: Ablation of the rightward inferior extension was unsuccessful in eliminating DAVNNT; however, subsequent ablation of the LIE successfully eradicated the arrhythmia. Conclusion: This unique case, marked by the first instance of DAVNNT caused by LIE, diagnosed through ATP injection, underscores the utility of this diagnostic approach and broadens the spectrum of our understanding and management of this condition. [ABSTRACT FROM AUTHOR]