Localized rotors and focal impulse sources within the left atrium in human atrial fibrillation: A phase analysis of contact basket catheter electrograms
AIMS The purpose of our study was to determine the acute effects of complex fractionated electrograms (CFAE) ablation guided by automated detection on dominant frequency (DF) and regulatory index (RI) for the fibrillatory process. METHODS AND RESULTS The study included 41 patients (21 paroxysmal and 20 persistent) referred for catheter ablation of atrial fibrillation (AF). Our ablation strategy included pulmonary vein isolation (PVI) as first step, CFAE ablation as second step, roof line ablation as next, and mitral isthmus ablation as last step. On the CFAE map, we were targeting only points outside the previous PVI lines. Simultaneously, we evaluated DF and RI changes in the coronary sinus after each step of ablation. The termination rate by CFAE ablation was low (12.5% in paroxysmal and 10% in persistent AF). Changes in DF and RI after CFAE ablation were not significant (<0.25 Hz and max. 0.02 increase for RI) compared with other ablation steps. Pulmonary vein isolation, roof line, and mitral isthmus ablation resulted in significant changes in DF and RI. CONCLUSION On the basis of our results, CFAE ablation guided by a dedicated software algorithm and performed after standard PVI without CFAE remapping does not influence the fibrillatory process significantly. Application of a modified algorithm with different settings warrants further investigations.