B-PO05-096 USING REENTRANT MODE IN A REAL-TIME DYNAMIC SOFTWARE (LIVEVIEW) IN IDENTIFYING PV GAPS AND CONDUCTION BLOCKS DURING PV ISOLATION

Abstract

The identification of post pulmonary vein isolation (PVI) gap by traditional activation and voltage maps are time-consuming. To investigate the characteristics, efficiency and accuracy of LiveView, a novel dynamic software, in identifying the post PVI gaps and block lines. Patients with PAF who failed to achieve first-pass PVI and with recurrent PAF were enrolled. The gap location was confirmed by activation and propagation maps. Of 25 PVs with gaps, 110 frames on gaps and 124 frames on conduction block lines were analyzed by using LiveView (EnSiteTM Dynamic Display). We defined isochronal crowding in the LAT mode as 3 colors between 2 adjacent electrodes. Each frame was classified as with or without isochronal crowding in LAT mode and one color or continuous color or isochronal discontinuity in reentrant mode. The gray color seen inside the pulmonary veins was considered to represent conduction block. Presentations of gap and block line in LiveView are shown in table 1. LAT mode demonstrated isochronal crowding on both the gap and block line, but reentrant mode showed isochronal discontinuity only on the block line (figure 1A). The sensitivity and specificity of isochronal discontinuity or gray color in reentrant mode to identify block line were 56.45% and 100%, respectively. The sensitivity and specificity of isochronal crowding or gray color in LAT mode to identify block line were 50.8% and 64.5%, respectively. Reentrant mode in LiveView is more accurate than LAT mode in identifying block lines at PV. We proposed an efficient, practical algorithm to differentiate the block line from PV gaps during AF ablation procedure (Figure 1B).