A: An A-A-V response. Note that this response was followed by the tachycardia with the short VA interval. B: A change in the atrial activation sequence during an application of radiofrequency (RF) current. The RF ablation (Abl) at the origin of the AT converted the activation from an eccentric to a concentric atrial activation pattern. 

Contexts in source publication

Context 1

... AV nodal reentrant tachycardia (AVNRT), but the ec- centric atrial activation pattern disagrees with an AVNRT. For a reconfirmation, we repeated the ventricular overdrive pacing during the tachycardia. It is noteworthy that one of the several pacing attempts showed a different response, which was an atrial-atrial-ventricular (A-A-V) response ( Fig. 2A). An A-A-V response was observed when the resumed tachy- cardia after pacing had the short VA interval, while the A-V response occurred for the tachycardia with the very short VA interval. This suggested AT as the mechanism underlying the tachycardia, but a concurrent AVNRT should exist when the VA interval was very short. It appears ...

Context 2

... mapped the right atrium and found a focal activa- tion with the earliest activation at the interatrial septum superoposterior to the His bundle region. Radiofrequency energy delivered at that site altered the atrial activation se- quence from eccentric to concentric (Fig. 2B), indicating that the elimination of the AT made the AVNRT obvious. A slow pathway ablation was performed, and eventually, no tachycardia was any longer seen or inducible in this patient. retrograde fast pathway and reset the origin of the AT. Mean- while, the impulse also entered the antegrade slow pathway and generated the next ...