Background
A new dual energy catheter allows toggling between radiofrequency ablation (RFA) and pulsed field ablation (PFA) while performing point-by-point ablation. This enables electrophysiologists to follow individualised ablation concepts for atrial fibrillation (AF) while using efficient RFA at thicker walls and PFA at the posterior LA wall to avoid oesophagal heating. Real-world data on intraprocedural effectiveness and short-term clinical outcomes with this hybrid approach remains limited.
Methods
Consecutive patients with atrial fibrillation (AF) undergoing their first pulmonary vein isolation (PVI) were included. PVI was performed with focal, point-by-point ablation, creating contiguous wide-antral encirclement of ipsilateral pulmonary veins using a contact-force sensing dual-energy THERMOCOOL SMARTTOUCH SF (DE STSF) catheter and the TRUPULSE multimodality generator (Biosense Webster, Inc.). Pulsed-field ablation was applied to posterior/inferior segments with a target ablation index (AI) of 400, and radiofrequency (RF) to anterior/ridge/carina segments with a target AI of 550. First-pass isolation was assessed and documented after each encircling. In the event of reconduction, additional ablation was performed, and gap segments were recorded. Clinical follow-up at 3 and 6 months included at least two 48-hour Holter ECGs and a clinic evaluation.
Results
We included 62 consecutive first-procedure AF patients (age 68.1 ± 9.3 years; 41/62 (66.1%) male; CHA₂DS₂-VASc 2.8 ± 1.4; paroxysmal AF 27/62 (43%)). Median total procedure time was 91.0 (79.0–114.2) min, with total effective ablation-delivery time 21.0 (18.0–26.0) min. The number of applications per case was 63.0 (40.0–84.5) for RF and 42.7 (32.0–65.0) for PF. Additional ablation lesions were applied in 14 (22.6%) patients. PVI was achieved in all patients at the end of the procedure. First-pass isolation was documented in 52/62 (84%) patients and in 112/124 (90%) pulmonary vein (PV) pairs. Reconduction occurred more frequently in the right PV encirclement (8 right PV pairs vs 4 left), with the right posterior carina involved in 6/8 right-sided cases.
Short-term follow-up (3 and 6 months): data collection is ongoing and will be reported once analysed.
Conclusion
The new dual-energy STSF catheter enabled feasible procedural times and excellent acute PV isolation. Despite an overall low intraprocedural reconduction rate, reconduction is clustered in right-sided PV pairs, particularly at the right posterior carina, suggesting a region prone to gaps that may merit targeted attention. Short-term (3/6-month) outcomes will be reported upon completion of follow-up.
