B-PO05-077 VISUALIZATION OF ELECTROGRAPHIC FLOW FIELDS OF INCREASING COMPLEXITY DURING SINUS RHYTHM, PACING AND PERSISTENT AF

Abstract

Electrographic flow (EGF) mapping is a novel method of estimating in vivo, near real-time cardiac action potential flow to visualize flow fields of wavefront propagation. Describe the use of EGF mapping to visualize a variety of atrial rhythms in an animal model. Using a 64-electrode basket catheter, 1 minute unipolar electrograms were recorded in both atria to generate EGF maps and their corresponding streamline origin plots. Calculated flow vector fields are analyzed to detect singularities in a 3x3 pixel window where flow vector angles around a point cover 360°. Divergence, rotation, and velocity define the flow field around a singularity in a 1 electrode distance as an active source (focal or rotational) v. a passive rotational phenomenon. EGF was recorded in 1 SR and 2 rapid atrial pacing animals 1-2 weeks and persistent AF for 3 months. Three hundred and five EGF maps and streamline origin plots were recorded during a variety of rhythms (Figure A-F). SR revealed focal automaticity from the sinoatrial node with homogenous wavefront propagation throughout healthy right atrium (A). Atrial tachycardia shifts the site emanating flow with change in direction of wavefront propagation v. SR (B). The integrity of an RF linear lesion can be easily defined (C). Mapping in AF revealed focal sources. In addition to putative AF sources, there were passive rotations also seen (D). During AF, high output pacing simulates a source (E), while subthreshold pacing does not affect flow (F). EGF mapping is an effective new technology capable of recording and visualizing complex atrial activity and may define ablation targets during AF.