Beyond the Learning Curve: How Operator Experience Affects Pulsed-Field Ablation Outcomes.

Background The learning curve for pulmonary vein isolation (PVI) using "single-shot" pulsed-field ablation (PFA) is thought to be short. 3D electro-anatomical mapping (3D-EAM) might provide adjunctive information to shorten the learning curve and improve lesion durability.Objective To analyze procedural performance markers over time for PVI using PFA and 3D-EAM.Methods Consecutive patients undergoing PVI with PFA were included. 3D-EAM was used based on operator's experience and the planned lesion set. Patients were followed using 7d-Holter ECG at 3, 6, and 12 months. During clinically indicated repeat ablations, 3D-EAM was used to assess PVI durability.Results A total of 1008 AF patients underwent a first PVI using PFA. 3D-EAM was used in 457 patients (45%). Using an exponential fit function, the learning curve was estimated at 18 procedures for procedure time and 8 for fluoroscopy time per operator. Using a learning curve cut-off of 20 cases per operator, 12-month freedom from arrhythmia recurrence was similar during (n=224) and after (n=784) the learning curve 65% vs. 68%, p=0.52). Similarly, the use of 3D-EAM did not affect outcomes (69% without 3D-EAM vs. 64% with 3D-EAM, p=0.50). PVI durability increased from 201/332 veins (61%, <60 procedures per operator) to 82/112 veins (73%) thereafter (p=0.017).Conclusion While the learning curve for "single-shot" PFA is around 20 cases per operator based on procedure and fluoroscopy times, improvements in long-term PVI durability were observed after 60 cases. No difference in freedom from arrhythmia was observed during the learning curve or by using 3D-EAM.