Date of download: 7/5/2016 Copyright © The American College of Cardiology. All rights reserved. From: Validation of the Noncontact Mapping System in the Left Atrium During Permanent Atrial Fibrillation and Sinus Rhythm J Am Coll Cardiol. 2006;48(3): doi: /j.jacc A reconstructed virtual endocardial geometry of the left atrium. The left atrium is viewed from four perspectives as indicated by the human torso. The noncontact mapping array is represented in yellow in the center of the geometry. The mapping ablation catheter can be seen positioned on the posterior surface of the left atrial appendage. LAA = left atrial appendage; LIPV = left inferior pulmonary vein; LSPVos = left superior pulmonary vein; MV = mitral valve. Figure Legend:

Date of download: 7/5/2016 Copyright © The American College of Cardiology. All rights reserved. From: Validation of the Noncontact Mapping System in the Left Atrium During Permanent Atrial Fibrillation and Sinus Rhythm J Am Coll Cardiol. 2006;48(3): doi: /j.jacc Intracardiac electrograms downloaded for cross correlation with the mapping catheter positioned in the left atrial appendage as seen in Fig. 1. On each panel from top to bottom, electrocardiographic (ECG) lead V 1, the unipolar contact electrogram (Uni MDU D), and the virtual unipolar electrogram (EnGuide virtual) are shown recorded at the endocardial surface where the map catheter is positioned. The top panel is before a bolus of adenosine was given and the bottom panel during an atrioventricular block induced by adenosine. In this example, the correlation coefficient (r) between the contact and virtual electrograms is 0.72, but it deteriorates to 0.53 during the adenosine bolus. The time units are in milliseconds. Figure Legend:

Date of download: 7/5/2016 Copyright © The American College of Cardiology. All rights reserved. From: Validation of the Noncontact Mapping System in the Left Atrium During Permanent Atrial Fibrillation and Sinus Rhythm J Am Coll Cardiol. 2006;48(3): doi: /j.jacc These box and whisker plots demonstrate the impact that distance of the catheter from the center of the array has on the cross correlation between virtual and contact atrial electrograms (top), timing error between the two atrial electrograms (middle), and the root mean square (RMS) amplitude of the virtual electrogram (bottom) during sinus rhythm. The box represents the interquartile range and the thick line represents the median value. The whiskers depict the 5th and 95th percentiles. A Mann-Whitney U test was performed to test whether there was a significant difference between points 40 mm from the center of the array. Deterioration was found in both the correlation and timing difference the further the catheter was from the center of the array. However, the amplitude of the virtual electrogram also was reduced the further the catheter was away from the array. Figure Legend:

Date of download: 7/5/2016 Copyright © The American College of Cardiology. All rights reserved. From: Validation of the Noncontact Mapping System in the Left Atrium During Permanent Atrial Fibrillation and Sinus Rhythm J Am Coll Cardiol. 2006;48(3): doi: /j.jacc Box and whisker plots demonstrating the cross correlation (top) and timing error (bottom) between virtual and contact far field ventricular electrograms during sinus rhythm. The box represents the interquartile range and the thick line represents the median value. The whiskers depict the 5th and 95th percentiles. The correlation is excellent, and there is no deterioration with increasing distance form the center of the array. Figure Legend:

Date of download: 7/5/2016 Copyright © The American College of Cardiology. All rights reserved. From: Validation of the Noncontact Mapping System in the Left Atrium During Permanent Atrial Fibrillation and Sinus Rhythm J Am Coll Cardiol. 2006;48(3): doi: /j.jacc A box and whisker plot of the cross correlation between virtual and contact electrograms measured during atrial fibrillation. The box represents the interquartile range and the thick line represents the median value. The whiskers depict the 5th and 95th percentiles. There was a clear deterioration in the level of correlation the further the catheter was away from the center of the array, and points >40 mm were significantly worse than those <40 mm; 0.67 (0.22 to 0.96) versus 0.75 (0.22 to 0.96) (p = 0.01). Figure Legend:

Date of download: 7/5/2016 Copyright © The American College of Cardiology. All rights reserved. From: Validation of the Noncontact Mapping System in the Left Atrium During Permanent Atrial Fibrillation and Sinus Rhythm J Am Coll Cardiol. 2006;48(3): doi: /j.jacc A box plot demonstrating the cross correlation between virtual and contact unipolar electrograms (top) and distance from the center of the array (bottom) with the ablation catheter at different anatomical sites in the left atrium during AF. The box represents the interquartile range and the thick line represents the median value. The left pulmonary veins and atrial appendage have the worse correlation, but they were also the furthest from the array. Ant = anterior wall of left atrium; LAA = left atrial appendage; LPV = left pulmonary veins; Post = posterior wall of left atrium; Roof = roof of the left atrium; RPV = right pulmonary veins. Figure Legend: