Atrioventricular Nodal Reentrant Tachycardia: What Have We Learned from Radiofrequency Catheter Ablation?

Atrioventricular (AV) nodal reentrant tachycardia (AVNRT) is the most common form of paroxysmal supraventricular tachycardia encountered in clinical practice. Following the introduction of radiofrequency (RF) current for catheter ablation, the initial procedure targeted fast AV nodal pathway (FP) conduction via delivering RF current to the antero-superior aspect of the tricuspid annulus. However, because of a high rate of producing complete AV block, selective ablation of SP conduction via delivering RF current to the posteroinferior septal right atrium close to the CS ostium has become the method of choice. Several investigators have addressed the issue of safety and efficacy of RFCA of AVNRT in the elderly. Observations and experiences described in the literature have provided paramount information regarding the mechanism of AV nodal reentry, and precautious measures needed to be taken for therapeutic intervention in various clinical settings.