Purpose: Ripple map (RM) is a novel method for displaying activation pattern on the surface of a cardiac chamber. The aim of this study was to determine the utility of the RM in interpreting the atrial propagation in atrial tachycardia (AT) in comparison with a conventional local activation (LAT) map.
Methods: Three-dimensional electroanatomical mapping and ablation of AT were performed using multielectrode catheters and the CARTO3 ConfiDENSE Module (Biosense Webster). LAT maps and RMs were retrospectively reviewed by two independent observers who were blinded to the ablation results.
Results: High-density maps (1683 ± 1362 points) of 45 ATs (274 ± 64 ms; macroreentry 28, focal 17) were obtained in 39 patients. Of the 45 ATs, 41 (91%) were terminated by catheter ablation. A retrospective review of the LAT map alone by two observers resulted in correct diagnosis in 27% (12 ATs), whereas additional reviews of the RMs improved the diagnostic accuracy to 80% (36 ATs, P < 0.001). The diagnostic accuracy using the RM was equally high for macroreentrant (79%) and focal ATs (82%, P = 1.000). Of the 33 LAT maps in disagreement with the observers, adjusting the window-of-interest (WOI) after reviewing the RMs achieved diagnostic agreement of 91% (30 ATs).
Conclusion: RMs allow us to have precise understanding of the atrial propagation on high-density CARTO maps for both focal and macroreentrant ATs, which is particularly useful for cases with difficult-to-interpret LAT maps.
Keywords: Atrial tachycardia; Catheter ablation; Local activation time; Ripple map.