BACKGROUND The MRI-compatible electrophysiology system previously used for MR-guided left ventricular electroanatomic mapping was enhanced with improved MR tracking, an MR-compatible radiofrequency ablation system and higher-resolution imaging sequences to enable mapping, ablation, and ablation monitoring in smaller cardiac structures. MR-tracked navigation was performed to the left atrium (LA)...

F ocal atrial tachycardias (ATs) surrounding the region of the anterior atrial septum (AAS) and their characteristic P waves, electrophysiological characteristics and catheter abla-tion results have been the subject of previous reports. 1–10 The close proximity to the atrioventricular (AV) node and the complex anatomy of this region continue to pose challenges during catheter ablation, and alth...

BACKGROUND Radiofrequency ablation (RFA) for atrioventricular nodal reentrant tachycardia appears to reduce atrial tachycardia, which might relate to parasympathetic denervation at cardiac ganglionated plexuses. METHODS AND RESULTS Compared to 7 control canines without RFA, in 14 canines, RFA at the bottom of Koch's triangle attenuated vagal stimulation-induced effective refractory periods pr...

Introduction: The ablation technique is one of the important therapeutic interventions for treatment of AV Nodal tachyarrhythmia. Different animal models have been developed to study the effects of ablation on the functional interanodal structure. The aim of the present study was to develop a new model of computer analysis to produce lesions by using direct voltage in isolated perfused rabbi...

Approximately 30% of all accessory pathways are located in the “septal” area. As these pathways are close to the atrioventricular node, there is an increased risk of right bundle branch block or inadvertent complete atrioventricular block during catheter ablation. Lesions created by radiofrequency (RF) energy inevitably involve some degree of tissue disruption and are irreversible. As cryotherm...

A single suction electrode catheter was used for His bundle electrogram recording. His bundle pacing, and low-energy (20 or 30 J) His bundle ablation in seven dogs. The suction electrode catheter was actively fixed to the atrial endocardium at the His bundle level. Electrophysiologic studies were performed in the control state, immediately after, and late (greater than 40 days) after His bundle...

observed that the sinus wave reached the AV node with a Introduction Atrioventricular septal defect (AVSD) can be associated with supraventricular arrhythmias and atrial fibrillation (AF). The position of the conduction system differs from the normal heart: the atrioventricular (AV) node is more posterior and inferior compared with the normal position in the triangle of Koch, in close relation ...

AIMS To evaluate the incidence, mechanism, and clinical implications of atrioventricular (AV) block during catheter radiofrequency (RF) ablation of the cavotricuspid isthmus (CTI). Although RF ablation of atrial flutter is the most frequently performed ablation procedure, data on the incidence and significance of an AV block occurring during the procedure are scarce. METHODS AND RESULTS Conse...