Catheter Ablation -> SVT/AVNRT/WPW/AT: -> Ablation Techniques D-PO05 - Poster Session V (ID 39) Poster

D-PO05-149 - In Vitro Lesion Size Assessment Of The Catheter-tip Angle To The Contact Tissue With High-power Short-duration Ablation (ID 1512)


Background: Recently, high-power short-duration (HP-SD) ablation in pulmonary vein isolation (PVI) of atrial fibrillation has been tested. In the clinical situation, the catheter tip-tissue surface angle varies during PVI. Nonetheless, the difference in the lesion size with catheter-tip angle to the contact tissue has not been clarified.
Objective: We investigated the difference in the lesion size for 3 types of catheter-tip angles.
Methods: We conducted an in vitro study using porcine LV tissue in saline baths, and compared the lesion size (endocardial diameter, maximum diameter, and depth) during the HP-SD method (45W, RF-time of 5 sec, contact force of 10g), for each angle (horizontal to the surface [90°], 45°, and parallel to the surface [0°]) .
Results: For each setting, the ablation index (AI) was reached at around 300 and there were no significant difference (292±2.1, 296±6.2, 296±2.7, p=0.71). The endocardial diameter was significantly larger at 0° than 45° and 90°(6.1±0.2mm, 5.1±0.2mm, and 5.3±0.3mm, p<0.05), but the lesion depth was significantly more shallow (2.1±0.1mm, 2.8±0.2mm, 2.8±0.1mm, p<0.05) in the 0°group than other groups. The maximum lesion size tended to be smaller at steeper angles (6.8±0.1mm, 6.5±0.2mm, and 6.2±0.1mm, p<0.1) (Figure).
Conclusion: Lesions were wider but with less depth as the catheter-tip angle became steeper. To create continuous lesions, the ablation tag interval should be narrower with catheter-tip angles of 90 or 45° as compared to that derived when the catheter-tip is located parallel to the surface (catheter-tip angle 0°), but an additional RF time and AI may be required for a catheter-tip angle of 0° to create transmural lesions.