Radiofrequency catheter ablation of AV nodal reentry: the anterior approach.

The ability to cure atrioventricular (AV) nodal reentry with radiofrequency catheter ablation with preservation of antegrade conduction represents a significant clinical advance. It also provides an opportunity to better understand the pathophysiology of this fascinating arrhythmia. Two techniques have been developed for ablation of AV nodal reentry. The first to be described used lesions made anteriorly near the apex of the triangle of Koch. More recently, lesions applied posteriorly, adjacent to the ostium of the coronary sinus, have been used. The purpose of this article is to describe the technique and electrophysiological effects of the anterior approach. Methods for minimizing the risk of high grade AV block will also be discussed. Results of a prospective comparison of anterior and posterior lesions for treatment of AV nodal reentry will be reviewed. Based on these data, recommendations for the clinical role of the anterior approach will be made.