Unique electrophysiological properties of fast‐slow atrioventricular nodal reentrant tachycardia characterized by a shortening of retrograde conduction time via a slow pathway manifested during atrial induction

• DOI: 10.1111/jce.14501
• Publication Date: 2020-04-16T13:51:12Z
• Authors: Shuntaro Tamura; Tadashi Nakajima; Takashi Iizuka; Hiroshi Hasegawa; Takashi Kobari; Masahiko Kurabayashi; Yoshiaki Kaneko
• Keywords: Reentry; Atrioventricular node; Atrioventricular reentrant tachycardia

Abstract Introduction Electrophysiological properties of reentry circuits fast‐slow atrioventricular nodal reentrant tachycardia (F/S‐AVNRT) may contribute to cyclic variability after atrial induction. Methods In 156 inductions 33 patients with F/S‐AVNRT, we measured the atrio‐His (AH) and His‐atrial (HA) intervals in first cycle induction (AH[1] HA[1], respectively), those second (AH [2] HA [2], during that maintained a stable length AH[T] HA[T], calculated value AH(1) minus AH(T) [ΔAH] HA(1) HA(T) [ΔHA] each According sum ΔAH ΔHA, was classified as incremental (<−20), balanced (−20 20), or decremental (>20). Results ΔHA were significantly different between three responses: 6 ± 28 −67 39 55 (35%) an response, 20 10 −23 59 (38%) 54 44 4 50 42 (27%) respectively. Incremental response reproducibly consistently observed 33% patients. HA(2) similar response. These results suggest can be manifested only when is excessively shortened, approximating retrograde conduction time over slow pathway, contrast, far superior delay AH(1). Conclusion specific poorly recognized, electrophysiological shortening pathway