Posterior wall isolation via a multi-electrode radiofrequency balloon catheter: feasibility, technical considerations, endoscopic findings and comparison with cryoballoon technologies

BackgroundPosterior wall (PW) isolation is an important adjunctive ablation target in patients with non-paroxysmal atrial fibrillation (AF). Traditionally performed with point-by-point radiofrequency (RF) ablation, PW isolation has also been performed with different cryoballoon technologies. We aimed at assessing the feasibility of PW isolation with the novel RF balloon catheter Heliostar (TM) (Biosense Webster, CA, USA).MethodsWe prospectively enrolled 32 consecutive patients with persistent AF scheduled for first-time ablation with the Heliostar (TM) device. Procedural data were compared with those from 96 consecutive persistent AF patients undergoing pulmonary vein (PV) plus PW isolation with a cryoballoon device. The ratio RF balloon/cryoballoon was 1:3 for each operator involved in the study, aiming at avoiding any imbalance related to different experience.ResultsSingle-shot PV isolation was documented in a significantly higher number of cases with the RF balloon technology compared to cryoballoon ablation (89.8% vs. 81.0%; p = 0.02, respectively). PW isolation was achieved with a similar number of balloon applications between the two groups (11 +/- 4 with the RF balloon versus 11 +/- 2 with the cryoballoon; p = 0.16), but in a significantly shorter time among RF balloon patients (228 +/- 72 s versus 1274 +/- 277 s with cryoballoon; p < 0.001). Primary safety endpoint occurred in none of the RF balloon patients versus 5 (5.2%) patients in the cryoballoon group (p = 0.33). Primary efficacy endpoint was achieved in all (100%) RF balloon patients versus 93 (96.9%) cryoballoon ones (p = 0.57). Oesophageal endoscopy did not show any signs of thermal lesions in RF balloon patients with luminal temperature rise.ConclusionsRF balloon-based PW isolation was safe and promoted shorter procedure times compared to similar cryoballoon-based ablation procedures.

Automated summary

This study aimed to evaluate the feasibility of posterior wall isolation using the RF balloon catheter. The results showed that the RF balloon technology had a higher success rate in single-shot pulmonary vein isolation compared to cryoballoon ablation. The number of balloon applications for posterior wall isolation was similar between the two groups, but the RF balloon technology had a significantly shorter procedure time.