Ripple Mappingによる右下葉結節延長から下部結節束への右房結節回帰性頻拍における推定信号の同定

Mapping wavefronts within the Triangle of Koch(ToK) is challenging due to multiple small and large amplitude signals within a short time-interval. Ripple Mapping was designed to overcome these limitations.

We tested the feasibility of delineating wavefronts within the ToK during slow-fast AVNRT.

Patients undergoing electrophysiological studies were recruited. Right-atrial CARTO maps were collected during atrial-pacing, ventricular-pacing and typical AVNRT. Using Ripple Mapping we marked; His activation during atrial-pacing, earliest retrograde atrial activation during ventricular-pacing, earliest signal during AVNRT(E-AVNRT) and earliest retrograde right-atrial activation during AVNRT.

72pts were recruited, with typical AVNRT in 40pts and full mapping protocol in 30pts(6327±948points collected). The E-AVNRT was 14.7±5.3mm inferior to earliest His identified during atrial-pacing. A wavefront consistent with slow-pathway activation started at E-AVNRT taking 22.2±4.8ms to reach the His-cloud with a line of block demarcating the atrial side. This same line formed the ventricular border of atrial activation during atrial-pacing, consistent with slow-pathway activation over the Right Inferior Nodal Extension(RINE). These wavefront signals became sharper approaching His but consistently activated a region inferior to His-cloud consistent with RINE activating the Lower Nodal Bundle. Earliest retrograde fast-pathway mediated right-atrial activation during AVNRT was 57.3±27.1ms later and 11.7±6.0mm from E-AVNRT and distinct from earliest atrial activation during ventricular-pacing(7.0±3.2mm). Successful ablation sites were closer to E-AVNRT than unsuccessful sites (6.4±3.0vs14.8±5.6mm;95% CI:5.2-7.6vs12.2-17.4mm,p<0.01).

Ripple Mapping can delineate slow and fast pathway activation during AVNRT. Lower Nodal Bundle signals 'lead' during AVNRT, inferior to the conventional His-cloud. Ripple Mapping-guided AVNRT ablation may be feasible.