The distance between the vein and lesions predicts the requirement of carina ablation in circumferential pulmonary vein isolation

Aims: Additional ablation in the pulmonary vein (PV) carina region is sometimes required to achieve electrical isolation following circumferential pulmonary vein isolation (PVI). This study investigated the procedural predictors for the requirement of additional carina ablation to achieve complete electrical isolation with PVI. Methods and results: Eighty patients with drug-refractory paroxysmal AF underwent circumferential PVI. After the first round of PVI, we placed circular catheters inside the veins to identify the residual PV potentials, and also performed electroanatomic mapping to observe the earliest activation sites during sinus rhythm. The requirement of an additional gap and carina ablation, and the optimal distance that predicted an incomplete PV block were assessed. In the first 40 patients, 43% of the ipsilateral PVs were electrically isolated after the initial PVI. Subsequent ablation of the gaps and ablation of the carina were required in the remaining 57% PVs. The only predictor of the requirement of carina ablation was the mean distance between the lesion-related scar and the ostia (P = 0.03). The longer the distance from the isolating lesions to the PV ostia (>8 mm) predicted an incomplete PV isolation after the first round of circumferential isolation. In the next 40 patients, a fixed distance of 8 mm to the PV ostia decreased the requirement of a carina ablation and resulted in a shorter procedure time (P < 0.05). Conclusion: sThis study indicated the importance of complete linear lesions and additional carina ablation when the wide area circumferential PV isolation was applied.