Optimal power settings have major impact on procedural efficiency in pulmonary vein isolation guided by robotic magnetic navigation.

Introduction: Early reports on pulmonary vein isolation (PVI) for atrial fibrillation (AF) guided by robotic magnetic navigation (RMN) show comparable results to manual radiofrequency (RF) or cryoballoon ablation; however, lengthy procedures were reported. This could be due to suboptimal lesion formation caused by a lack of user experience and defined best practices. Operators performed RMN-guided RF ablation with lower power settings, presumably leading to longer procedures. In this study, we aimed to re-evaluate safety and efficiency of RMN-guided PVI for AF based on delivered radiofrequency power.

Methods: Patients undergoing RMN-guided ablation were screened, and consecutive patients with AF undergoing PVI-only between 2008 and 2023 were retrospectively enrolled. Patients were grouped by the power settings utilized during the PVI procedure (group 1-25-30W, group 2-30-35W, group 3-35-40W, group 4-40-45W, group 5-45-50W, and group 6-50-55W). We collected and analyzed demographic data: age, sex, and AF type; safety data: intra- and post-procedural complications; procedural data: procedure duration, fluoroscopy time, RF ablation time, RF application number, and success rate; and follow-up data: AF recurrence and number of redo procedures.

Results: From the total number of 3398 screened patients, 238 patients met the inclusion criterion of undergoing PVI-only procedure (mean age 60.4 ± 9.9 years, 63.8% male). Throughout the 15 years only five patients had major (2.2%) and 15 patients had minor complications (6.6%), without differences between the patient groups (p = 0.40 and p = 0.63). The mean procedure duration was progressively decreased with the use of higher RF power (273.9 ± 97.0, 179.8 ± 104.0, 134.9 ± 55.3, 134.0 ± 39.5, 118.1 ± 41.3, and 110.9 ± 39.0 min, respectively; p < 0.001). Median fluoroscopy time was 19.5 min (IQR 13.0-35.5), progressively decreasing within the power groups (58.2 ± 20.5, 40.5 ± 26.2, 15.9 ± 6.6, 17.8 ± 8.1, 17.4 ± 7.5, and 19.8 ± 9.3 min; p < 0.001). We found differences between the power groups in RF application number (p < 0.001) and RF application duration (p = 0.003). Successful PVI was achieved in 238 patients (100.0%). Twenty-one patients with paroxysmal AF (17.1%) and 31 patients with persistent AF (40.7%) had documented recurrence during the 12-month follow-up. We found no differences in AF recurrence between the patient groups (p = 0.18 and 0.66).

Conclusions: RMN-guided PVI-only for AF is safe and feasible. In contrast to early reports, procedure times and fluoroscopy use gradually decreased during the years, when increasing RF power was applied. Higher power settings during robotically-guided PVI did not compromise the safety of the procedures.