A novel approach to visualizing an underlying atrial arrhythmogenic substrate with high-density and high-resolution mapping during extrastimulation

Figures

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  Figure 1. A: Local activation time (LAT) maps acquired with 2 different coupling intervals on the left atrial posterior wall. Two LAT maps (left: S1 [600 ms], center: S2 [600–280 ms]) obtained simultaneously using the Parallel Mapping Module (Biosense Webster, Diamond Bar, CA) based on the intracardiac electrograms shown on the right side. Splines A, F, G, and H recorded during S1 recorded normal sharp potentials, while during S2 they recorded fragmented abnormal potentials. B: Voltage maps acquired with 2 different coupling intervals on the left atrial posterior wall. The width of the healthy region between the bilateral pulmonary vein isolation lines appeared slightly narrower in the S2 map. Still, there were no obvious low-voltage areas on the posterior wall. Other areas also exhibited healthy voltage in both maps. C: Intracardiac electrograms of atrial firing arising from the posterior wall of the left atrium. Atrial fibrillation arose from atrial firing following the administration of isoproterenol with the OCTARAY catheter (Biosense Webster) placed at the site where abnormal potentials had been recorded on the S2 map.

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  Figure 2. A: Local activation time (LAT) maps acquired with 2 different coupling intervals on the left atrial anterior wall. Two LAT maps (left: S1 [600 ms]), center: S2 [600–260 ms]) obtained simultaneously using the Parallel Mapping Module (Biosense Webster, Diamond Bar, CA) based on the intracardiac electrograms are shown on the right side. Splines A–F recorded during S1 recorded normal sharp potentials, while during S2 they recorded widespread fragmented abnormal potentials. B: Three voltage maps during pacing or atrial tachycardia. Although there were no obvious low-voltage areas of <0.5 mV in the S1 map, the S2 map revealed widespread low-voltage areas on the left anterior wall and around the left appendage. The voltage map acquired during atrial tachycardia (tachycardia cycle length 230 ms) was similar to the S2 map.