Intracardiac electrocardiographic finding using as a guide for selective catheter ablation in patients with AV nodal reentrant tachycardia (AVNRT) is not specific. Therefore, we evaluated the efficacy and safety of the anatomical approach for catheter ablation in patients with AVNRT.

Among the patients diagnosed as AVNRT by electrophysiologic study, total 66 patients (M:F=26:40) were included in this study. In the right anterior oblique radiographic view, the septal annulus of tricuspid valve, extending from the most posterior region of the annulus adjacent to coronary sinus ostium (posterior) to His bundle recording site (anterior), was divided into posterior (P), mid (M), and anterior (A) sites. Radiofrequency (RF) energies were applied from the posterior part to the anterior part sequentially along the septal annulus of tricuspid valve until successful ablation.

Successful anatomical sites were located in posterior (11 patients), mid (48 patients), and anterior (7 patients) sites. The most patients (62 patients) were treated with slow pathway ablation except 4 patients in whom fast pathway was ablated. Probable slow potentials were observed in 8 patients (12%, 3 in posterior sites and 5 in mid sites). Transient complete AV block followed by first degree AV block and delayed complete AV block was occured in one case whose ablation site was A1. And another 3 patients had postablation first degree AV block.

In patients with AVNRT, the ablated pathway were different according to successful anatomical site. And RF catheter ablation of atrioventricular nodal reentrant circuit guided by anatomical landmark is safe and efficacious.