Radiofrequency ablation of decremental accessory pathways mimicking “nodoventricular” conduction

Recent studies have shown that the previously proposed “nodoventricular” accessory pathways (Mahaim fibers) are usually right-sided accessory pathways with decremental conduction properties. 1,2 Successful ablation of these pathways using radiofrequency (RF) energy at the right atrioventricular (AV) annulus has been reported. 3,4 However, mapping techniques and electrogram criteria for successful ablation remain unclear. Because of the unusual properties of these pathways, such as decremental conduction and absent retrograde conduction, 5,6 traditional mapping techniques may not be applicable. The present study describes our experience ablating nodoventricular pathways using RF current.