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

D-PO02-143 - Feasibility, Safety And Efficacy Of Tailoring Ablation Index To Left Atrial Wall Thickness (LAWT) During Atrial Fibrillation Ablation. The “Ablate By-LAW” Study (ID 1029)


Background: Radiofrequency (RF) ablation of paroxysmal atrial fibrillation targeting specific criteria for ablation index (AI) results in durable PV isolation. Left atrial wall thickness (AWT) is a known determinant of lesion depth. Ablation parameters have never been adapted to AWT.
Objective: To determine if adapting AI to AWT is feasible, effective and safe.
Methods: 86 patients referred for paroxysmal AF ablation. AWT maps were derived from the multidetector computed tomography as the local distance between the LA endo and epicardium. The WT map was fused with the LA anatomy using CARTO-merge. AWT was categorized into 1mm-layers and AI was titrated to the AWT as follows: Thickness < 1 mm: 300; 1-2 mm: 350; 2-3 mm: 400; 3-4 mm: 450; >4 mm: 500. Max inter-lesion distance was set at 6 mm. AI settings were: catheter stability: min time 3 s, max range 4 mm; force over time: 25%, min force 3 g; lesion tag size: 3 mm. The circumferential ablation line was designed in a personalized fashion to avoid thicker regions.
Results: 86 patients [56 (54.9%) male, age 60 ± 11 years] with mean LVEF 60±5 %; Mean LA diameter 38 ± 5 mm; Mean AWT 1.36 ± 0.63 mm; Mean AI 352 ± 36 on the RPVs and 356 ± 36 on the LPVs; Overall RF time was 15 ± 3 min; Procedure time was 60 min (IQR 51-69). Fluoroscopy time was 57 s (IQR 34-93). First pass isolation was obtained in 82 (95.3%) of the RPVs and 80 (93%) of the LPVs.
Conclusion: The present study, assessing a personalized protocol that adapts AI to AWT during AF ablation, improves procedure efficiency by minimizing ablation and procedure time with a high rate of first pass isolation, as compared to previous PV ablation protocols. Further studies are needed to evaluate the long-term results of this approach.