PO-04-004 UTILITY OF OPEN-WINDOW MAPPING FOR CATHETER ABLATION OF ACCESSORY PATHWAY

Abstract

Open window mapping (OWM) is a novel automated mapping methods for catheter ablation of an accessory pathway (AP), in which the local signal is annotated with the windows of interest parameters set to analyze both atrial and ventricular signals. We sought to determine the utility of the OWM to identify the location of APs in patients with APs. In this two-center study, 28 patients (20 male, 55 years old: IQR 22-67) who underwent high-density OWM with extended early-meets-late (EEML) algorithm (CARTO 3, Biosense Webstar, USA) using a 20-electrode, 5-spline catheter (Pentaray, Biosense Webster) were enrolled. The lower threshold of the EEML was set to adjust the EEML gap to match propagation mapping (Figure A) and the EEML gap of > 1cm was defined as a wide AP (Figure B). The median mapping points, mapping time, and lower threshold of EEML were 2399 points (1736-3798), 24 minutes (16-30), and 22 (18-25), respectively. APs were successfully eliminated in all 28 patients (22 APs in mitral annulus and six APs in tricuspid annulus), in 19 of which were eliminated by the first radiofrequency (RF) application (68%). OWM revealed wide or multiple APs in 10 patients (36%), in all of whom multiple RF applications were required to eliminate the APs. OWM facilitates to visualize the location and width of APs, which is particularly useful to predict whether linear or cluster ablation lesion sets are required for wide APs.