138-06: Evidence for a late effect of rotor ablation in patients undergoing redo procedure for atrial fibrillation

Abstract

Purpose: Stable electrical rotors and focal sources have been demonstrated to sustain atrial fibrillation (AF). Rotor activity can be demonstrated using a special computational mapping procedure. The aim of this study is to analyze the characteristics of the course of heart rhythm (AF recurrence and restoration of sinus rhythm) after rotor ablation. Methods: Patients who underwent redo procedure for AF (Focal Impulse and Rotor Mapping (FIRM) guided ablation and additional re-pulmonary vein isolation) were analyzed with respect to the time of AF recurrence and the characteristics of restoration of sinus rhythm (SR). Follow-up visits including 96h Holter and/or device interrogation were performed 3, 6 and 12 months after ablation procedure. Results: 44 patients (mean age 63 ± 9 years, 27 male) with recurrent AF (8 paroxysmal, 36 persistent) were included, all of them had undergone 6 month follow-up visit and 26/44 (59%) 12 month follow-up visit so far. We found 52% (23/44) of the patients in stable SR at 3 month, 66% (29/44) at 6 month and 88% (23/26) at 12 month follow-up, respectively. 50% (22/44) of the patients remained in stable SR during the complete follow-up period without any recurrence of AF or atrial tachycardia (AT). 32% (14/44) of the patients were in stable SR at the currently last follow-up even though a recurrence of AF had been observed before at 3 or 6 month follow-up (8 patients with cardioversion to SR between 3 and 6 months after procedure, 6 patients between 6 and 12 months, respectively). The cases of this patient group can be classified as follows: We have observed a spontaneous cardioversion to SR without any intervention for 6/14 (43%) patients (despite persistent AF before). 3/14 (21%) received an additional antiarrhythmic drug therapy (despite ineffectiveness before ablation), 3/14 (21%) underwent an electrical cardioversion and 2/14 (14%) a reablation procedure, respectively. Conclusion: In this single left study we have detected a remarkable increase of success rate over time for patients in stable SR after FIRM-guided ablation from 52% at 3 month follow-up to 88% at 12 month follow-up. We suppose, that there is an additional late effect of rotor ablation, maybe due to a kind of “reverse remodeling” of atrial substrate. Therefore, final ablation outcome should be assessed at the earliest 9 to 12 months after procedure.