Feasibility and efficacy of 50 W ablation with the TactiFlex catheter for the initial pulmonary vein isolation of atrial fibrillation.

Background: A novel contact force (CF) sensing catheter with a mesh-shaped irrigation tip (TactiFlexTM SE, Abbott), is expected to provide safe and effective radiofrequency ablation. Our previous study revealed that the TactiFlex catheter needs a higher power for pulmonary vein isolation (PVI) due to the long tip length. This study aimed to examine the feasibility and safety of a 50 W ablation with the TactiFlex for PVI of atrial fibrillation (AF).

Methods: A PVI was performed in 100 AF patients using TactiFlex catheters with a 50 W setting, 5-20 g CF, and 15-20 s ablation time. The primary outcomes included a successful PVI, the incidence of first-pass isolations (FPIs), the presence of PV conduction gaps, and the incidence of complications.

Results: FPIs were achieved for 82/100 (82%) right pulmonary veins (RPVs) and 87/100 (87%) left PVs (LPVs). Among the unsuccessful RPV FPIs, residual carina potentials were observed in 16/18 cases (89%), PV gaps in 1/18 cases (5.5%), and both carina and PV gaps in 1/18 cases (5.5%). Similarly, among the unsuccessful LPV FPIs, residual carina potentials were observed in 11/13 cases (84.6%), PV gaps in 1/13 cases (7.7%), and both carina and PV gaps in 1/13 cases (7.7%). Periesophageal nerve injury occurred in 1/100 cases (1%), and no cardiac tamponade occurred. The overall AF-free rate at one-year was 81.7%.

Conclusions: The 50 W ablation with the TactiFlex demonstrated a high rate of an FPI, low incidence of PV gaps, and proved to be a safe and effective approach for the initial PVI of AF.