Catheter Ablation -> Atrial Fibrillation & Atrial Flutter: -> Ablation Techniques D-PO02 - Poster Session II (ID 47) Poster

D-PO02-175 - Advantage Of Ablation Index-guided Atrial Fibrillation Ablation Over Force-time Integral-guided Ablation (ID 1045)


Background: Force-Time Integral (FTI) was used as a radiofrequency (RF) lesion marker in atrial fibrillation (AF) ablation. Ablation Index (AI) could estimate the lesion size more accurately and enabled high power applications more safely. However, the advantage of AI-guided ablation using target AI determined by FTI-guided ablation data over FTI-guided ablation with the same target FTI remains unclear.
Objective: To investigate the advantage of AI-guided ablation over FTI-guided.
Methods: We retrospectively investigated 981 patients undergoing AF ablation (median age, 67 (IQR 61-73) years; non-paroxysmal AF in 413 (42%)). All patients underwent circumferential pulmonary vein isolation (CPVI). We performed FTI-guided ablation in the first 263 patients (FTI), AI-guided with conventional RF power in the following 292 (AI-CP), and high power in the last 426 (AI-HP). The target AI was 400 at the left atrial (LA) anterior, 360 at posterior, and 260 on the esophagus, all of which were determined by retrospective analysis of FTI-guided with the same FTI target at 100. RF power was 30W at LA anterior, 20-25W at posterior, and 20W on the esophagus in the FTI group, 30-40W, 20-25W, and 20W, respectively, in AI-CP, and 50W, 40W and 25W, respectively, in AI-HP.
Results: The patient's characteristics were similar among the three groups. CPVI was completed in all patients. Procedure time was shortest in AI-HP (median 148 minutes (IQR 122-187)), followed by AI-CP (178 (149-228), p<0.0001 versus AI-HP) and FTI (192 (160-236), p=0.007 versus AI-CP). The percentage of all procedure-related complications was similar (1.5% in FTI, 2.4% in AI-CP, and 2.1% in AI-HP, p=0.36). No steam pop occurred in the three groups. Kaplan-Meire analysis (median follow up period: 351 days (287-394) in FTI, 269 (303-414) in AI-CP, and 184 (103-204) in AI-HP) showed similar AF free survivals (p=0.42 by log-rank test). AF-free survival rate at 180 days after ablation was 87% in FTI, 89% in AI-CP, and 92% in AI-HP.
Conclusion: Compared with FTI-guided ablation, AI-guided, especially high power ablation, shortens the procedure time without increasing complication events but does not necessarily improve the outcome when the target AI is determined by the data of FTI-guided ablation with the same target FTI.