1Herzzentrum der Universität zu Köln Elektrophysiologie Köln, Deutschland
Background For the treatment of AF pulmonary vein isolation (PVI) is the most efficient therapy. However, some patients experience recurrence of AF, require more than one catheter ablation (CA) and potentially substrate modification. The standard method for re-ablation is radiofrequency ablation (RFA) mostly not in a high power short duration (HPSD) mode. However, recent data proved efficacy and safety of HPSD for PVI and comparable outcomes to conventional RFA- and Cryo-PVI.
Aim The aim of this study was to compare complications and outcome of RFA ablation with conventional power settings to CA using HPSD in patients with recurrent AF after initially successful PVI.
Methods All AF re-ablation procedures from 12/2019–10/2022 performed at our center were analysed. Only patients with prior AF-ablation who completed follow up (FU) were included. In all procedures a 3D map using high density (HD) was obtained. Energy settings for RFA were either conventional (≤50W) or HPSD (70W). Ablation strategy was at operators’ discretion.
Results 245 procedures were analysed. In 205 procedures (83.7%) RFA ablation with conventional energy settings and in 40 (16.3%) HPSD was applied. In the RFA group (39.5% female; 68.8 y, 74.6% persAF) 105 (51.2%) patients had recovered PVs (persAF 70.5%) of whom 37 (35.2%) received only re-PVI. In 68 patients (64.8%) additional ablation lines and/or further substrate modification (CAFAE ablation/scar encirclement) were performed. In 100 patients (48.8%) PVI was durable (persAF 79.0%) but in 60.0% LA scar was detectable. In this group ablation strategies consisted of ablation lines (84%) and/or substrate modification (61.0%). In total, 145 patients (70.7%) of the conventional RFA group received additional ablation with LA-roof line as most prevalent lesion (44.9 %). 95 patients (46.3%) received further substrate modification and 74 (36.1%) additional AT/CTI-ablation. In the HPSD group (35.0% female, 67.0 y, 75.0% persAF) reconnection of PVs was observed in 25 (62.5%) patients (persAF 68.0%) of whom 6 (24.0%) received only re-PVI and 19 (76.0%) additional ablation lines and/or substrate modification. 15 patients showed durable isolation of pulmonary veins (86.7% persAF) with a LA scar in 60.0%. In these patients the ablation strategy was substrate modification (53.3%) and/or additional ablation lines (93.3 %). In the HPSD group, 33 patients (82.5%) received ablation lines, most frequently LA-roof line (68.0%), 19 (47.5%) substrate modification and 14 (35.0%) additional AT/CTI ablation.
The ablation time was shorter using HPSD (conventional 2017.3s, HPSD 1531.0s, p=0.007). 2 pericardial tamponades (1.0%) and 2 thromboembolic events (1.0%) were reported in the conventional group and no severe complication in the HPSD group. Non-severe complications were comparable (conventional: n=22, 10.7%; HPSD: n=9, 22.5%, p= 0.184). After a mean follow-up of 351 +/- 117 days 65.9% of patients were free from any atrial arrhythmia in the RFA group and 57.5% using HPSD (p=0.335). In the RFA group 27.3% experienced recurrence of AF compared to 20.0% after HPSD (p=0.308).
Conclusion In patients suffering from recurrent AF HPSD is an equally safe and efficient re-ablation method with significantly shorter ablation time compared to conventional RFA. Effective substrate modification and creation of lesion sets beyond PVI are feasible using HPSD in scarred LA with comparable arrhythmia free survival rates compared to standard RFA ablation.