J Korean Med Sci.  2000 Oct;15(5):494-500. 10.3346/jkms.2000.15.5.494.

Cellular electrophysiology of fast pathway ablation of rabbit atrioventricular node

• Yi KH
• Han HS

• KMID: 965868
• DOI: http://doi.org/10.3346/jkms.2000.15.5.494

Abstract

Discrete radiofrequency lesion at the atrial insertion site of the tendon of Todaro in the perfused rabbit preparation lengthens A-H interval, mimicking fast pathway input ablation. This study attempts to define the cellular electrophysiology of the ablation region prior to and after the elimination of fast AV node conduction. In six superfused rabbit AV node preparations, the cellular electrophysiology around the region of the atrial insertion to the tendon of Todaro was recorded using standard microelectrode technique prior to and after ablation. Before ablation, the action potentials recorded in the area of proposed lesion were exclusively from atrial or AN cells. At postablation, the superior margin of the lesion was populated with atrial or AN cells. AN, N, or NH cells bordered the lower part of the lesion. Electrophysiology of surviving cells at the edges of the lesion showed no significant changes in their Vmax, APD50 or APD90 and MDP from preablation values. Fast AV node pathway input ablation in the rabbit heart can be accomplished with a singular lesion around the atrial insertion site of the tendon of Todaro, involving atrial or AN cells. The results of the studies imply that inputs to the compact node may act as a substrate for successful ablation of AV node reentry tachycardia.

Keyword

Tachycardia,Atrioventricular Nodal Reentry; Catheter Ablation, Radiofrequency; Electrophysiology

MeSH Terms

Action Potentials/physiology
Animal
Atrioventricular Node/surgery*
Atrioventricular Node/physiology
Atrioventricular Node/cytology*
Catheter Ablation/methods*
Electrophysiology
Rabbits
Recovery of Function
Tachycardia, Supraventricular/surgery
Tachycardia, Supraventricular/physiopathology