Abstract 12207: Focal Impulse and Rotor Modulation-Guided Ablation More Efficiently Prolongs Atrial Fibrillation Cycle Length than Convention Ablation
Introduction: Prior studies have shown that atrial fibrillation (AF) cycle length (CL) prolongation is a marker for effective ablation, and predicts termination. We hypothesized that focal impulse and rotor modulation (FIRM) ablation, by targeting AF-sustaining sites, would have a greater impact on AF cycle length per unit of time of radiofrequency energy delivery than conventional (CONV), anatomically-based ablation.
Methods: In the CONFIRM trial, 64-electrode basket catheters were placed in the left and right atria of patients at AF ablation. Patients were enrolled in either the CONV arm, in which FIRM-blinded AF ablation was performed, and FIRM-guided ablation, in which electrical rotors and focal beats were identified and targeted in real-time for ablation. In the subset of patients in both arms in whom AF continued throughout ablation, we calculated the CL change (in msec, measured from the coronary sinus catheter as the average of 10 AF cycles) as a function of the total ablation time (in minutes of radiofrequency energy).
Results: A total of 30 patients were included in the analysis (11 FIRM, 19 conventional). Baseline CL was similar in both groups (181±25 CONV, 183±15 msec FIRM, p=NS) and after ablation (193±26 CONV vs 199±29 msec FIRM, p=NS). However, as illustrated in the figure, FIRM (blue bar) was significantly more efficient than CONV ablation (white bar) in prolonging AF CL per minute of RF ablation (0.56±0.65 vs 0.10±0.22 msec/min, p=0.03).
Conclusions: FIRM-guided more efficiently targets AF sustaining mechanisms than CONV ablation. Future studies should examine if this translates into improved procedural times.
- © 2012 by American Heart Association, Inc.