DISCUSSION
This study, in a controlled in-vivo environment, showed that the novel ICPM software was capable of accurately recognizing and mapping changing atrial foci. Whereas the operator was notified when the pacing site changed and switched maps accordingly, the software determined that the pacing site had changed on its own. Resultant maps were visually superposable. Quantitatively, local activation times and mesh vertices showed consistent matches >90% of the time. Pacing distances as close as 10 mm were assessed, and cycle lengths were kept constant to test the robustness of the system for distinguishing subtle differences in activation sites. This type of autonomous mapping capability could be of great benefit when targeting changing arrhythmia types, particularly in aforementioned conditions like atrial tachycardia, congenital heart disease and ventricular arrhythmias [7-9]. Additional advantages include automated filtering of mechanically induced ectopic activation that could introduce inaccuracies with manual mapping, particularly when cycle lengths are not radically different. Moreover, automated mapping can identify slight changes in signal morphology resulting from movements of the reference catheter that can otherwise go undetected.