Rotor mapping and ablation in persistent atrial fibrillation

Atrial fibrillation (AF) is the most frequently occurring sustained arrhythmia and causes significant morbidity and mortality. Targeted ablation of FIRM- identified rotors was not effective in obtaining AF termination, organization, or slowing during the procedure in non-paroxysmal AF patients. This chapter provides a brief overview of the technique and application of non-linear phase mapping in identification and ablation of localized AF sources. Phase mapping can provide both spatial and temporal information that help to reveal the electrical properties of the atrial matrix and offer additional insight into AF mechanisms. The chapter presents a novel two-step approach, namely the Taipei approach, to improve the identification and ablation of localized AF sources. Based on a fibrillatory electrogram morphology analysis with spatially stable small-radius reentries for maintaining AF, it proposes a non-linear waveform analysis to quantify the beat-to-beat morphological repetitiveness of the waveform patterns in the fractionated electrograms, namely the similarity index.