PO-04-038 ULTRA HIGH DENSITY MAPPING TO IDENTIFY MICRO-REENTRANT LEFT ATRIAL FLUTTER CIRCUITS WITHIN LOW BIPOLAR VOLTAGE REGIONS: A CASE SERIES

Micro-reentrant (MR) atrial flutter (AFL) circuits may not be evident with standard bipolar or multipolar mapping. We report 3 cases of left (LA) AFL where HD Grid + Omnipolar technology (Ensite X, Abbott) revealed MR within an area scar as noted by N/A Three patients prior LA ablation presented symptomatic AFL. mapping was done using the Ensite X system in Voxel mode. Bipolar voltage cutoff set at 0.3 to 0.05 mV. A 65-year-old CL 335 ms. Mapping Advisor spiral showed a large posterior wall and no circuit RA. Remapping identified 12 mm entire low which dense (Figure 1A). 59-year-old male 340 ms proximal distal CS activation. grid 21 mid fractionated mid-diastolic electrograms 1B 1C). Third patient 54-year-old who had posterolateral mitral annulus, otherwise Successful sites all did have identifiable electrogram on catheter (<0.05 mV, Figure 1 D). Low cut off during manually adjusted lowered 0.04 identify cases. This case series demonstrates that ultra high-density technology, dynamic adjustment threshold, enables identification circuits, leading successful ablation, critical isthmi were