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

D-PO02-176 - Impact Of Catheter Stability On Durability Of Pulmonary Vein Isolation (ID 240)

 M. Ohta: Nothing relevant to disclose.


Background: The left atrial (LA) - pulmonary vein (PV) reconnection after initial pulmonary vein isolation (PVI) is one of the main causes of atrial fibrillation (AF) recurrence. The stability of the catheter tip against the myocardial wall is important to achieve acute successful PVI. However, the objective evaluation method for catheter stability is not well-established and the effect of catheter stability on lesion durability is still unknown.
Objective: The purpose of this study is to evaluate impact of catheter stability on durability of PVI.
Methods: We included 27 consecutive patients who had undergone repeat catheter ablation due to AF recurrence after initial PVI using the CARTO system and the VisiTagTM module. The PVI line was devided into 12 areas by right/left, anterior/posterior, and superior/carina/inferior. The gap areas were defined where radio frequency ablation had changed the PV activation sequence or eliminated the PV potential in the repeat session. We investigated each VisiTagTM information of initial PVI; the ablation time, ablation power, catheter temperature, contact force, force time integral (FTI), ablation index (AI), impedance and the maximum distance to the adjacent tags (Dmax). We also evaluated appropriate force over time (FOT) setting to predict the LA-PV reconnection.
Results: The LA-PV reconnection were detected in 21 PVs out of 15 patients (55.6%) Of these 21 PVs, we assessed 436 tags, and 82 tags were in the gap area. The tags in the gap area had longer Dmax (6.86 ± 1.81 mm vs 5.83 ± 1.50 mm) and lower minimum contact force (3.26 ± 4.38 g vs 4.79 ± 4.91 g), although FTI, AI and impedance drop showed no significant differences. On multivariate analysis, longer Dmax was associated with the gap area (P<0.001). Among the tags with Dmax ≤6mm, 28 out of 242 tags were in the gap area, and the minimum contact force were significantly low in the gap area (2.25 ± 2.22 g vs 4.52 ± 4.83 g), while FTI, AI and impedance drop showed no significant differences. The FOT of 95% at the minimum force of 3g had a high negative predictive value (89.7%) for the gap area.
Conclusion: Once optimal inter-lesion distance has been acheived, catheter stability is the key for the durable lesion. The FOT of 95% at the minimum force of 3g can be the target of the catheter stability.