Abstract 5660: Location of Electrical Gaps after Cryoballoon Pulmonary Vein Isolation: Identification of Predilection Sites for Reconduction
Background: Cryoballoon (CB) ablation has the potential to simplify pulmonary vein isolation (PVI). However, initial studies indicate higher recurrence rates as compared to radiofrequency (RF) ablation. CB-PVI requires occlusive tissue contact during ablation. We hypothesized that conduction gaps leading to recurrent atrial fibrillation (AF) would preferentially occur at inferior sites, out of line of the main catheter pushing force.
Methods: 13 patients (pts) underwent repeat PVI for recurrent episodes of AF after the use of the single big cryoballoon technique for PVI in paroxysmal AF. After double transseptal puncture electro-anatomical mapping (Carto) of the left atrium (LA) was performed. A lasso catheter was inserted into each PV and sites of earliest PV activation were targeted using irrigated RF ablation. Ablation lines where continued around ipsilateral pairs of PV ostia until PV activation sequence change or reisolation occurred. For quantification, these lines were divided into 6 anatomical segments (Figure⇓).
Results: Individual PVs exhibited reconduction as follows: RIPV 11 pts (85%), LIPV 11 pts (85%), LSPV 10 pts (77%), RSPV 5 pts (38%). Segments most often affected by reconduction included the ridge between the lateral PVs and the LA appendage (LAA), particularly the inferior part (69%), and the inferior ostium of the RIPV (69%, Figure⇓). Total gap size was 51+/−37 (lateral) and 48+/−42 mm (septal).
Conclusion: The inferior LAA-PV ridge and inferior RIPV ostium are predilection sites for reconduction after CB-PVI. Techniques to enhance balloon-tissue contact in these regions may improve chronic success rates.