Bipolar mode radiofrequency ablation was more effective than unipolar mode in creating transmural lesions across ventricular sites up to 15 mm thick, except when surrounded by air or epicardial fat.
Does bipolar mode radiofrequency ablation improve the creation of transmural lesions compared to unipolar mode in computational models of the ventricular wall?
Computational modeling suggests bipolar radiofrequency ablation is generally more effective than unipolar ablation for achieving transmurality across ventricular walls, except in the presence of epicardial air or fat.
PURPOSE: The aim of this study was to compare the efficacy of bipolar (BM) vs. unipolar (UM) mode of radiofrequency ablation (RFA) in terms of creating transmural lesions across the interventricular septum (IVS) and ventricular free wall (VFW). MATERIALS AND METHODS: We built computational models to study the temperature distributions and lesion dimensions created by BM and UM on IVS and VFW during RFA. Two different UM types were considered: sequential (SeUM) and simultaneous (SiUM). The effect of ventricular wall thickness, catheter misalignment, epicardial fat, and presence of air in the epicardial space were also studied. RESULTS: Regarding IVS ablation, BM created transmural and symmetrical lesions for wall thicknesses up to 15 mm. SeUM and SiUM were not able to create transmural lesions with IVS thicknesses ≥12.5 and 15 mm, respectively. Lesions were asymmetrical only with SeUM. For VFW ablation, BM also created transmural lesions for wall thicknesses up to 15 mm. However, with SeUM and SiUM transmurality was obtained for VFW thicknesses ≤7.5 and 12.5 mm, respectively. With the three modes, VFW lesions were always asymmetrical. In the scenario with air or a fat tissue layer on the epicardial side, only SiUM was capable of creating transmural lesions. Overall, BM was superior to UM in IVS and VFW ablation when the catheters were not aligned. CONCLUSIONS: Our findings suggest that BM is more effective than UM in achieving transmurality across both ventricular sites, except in the situation of the epicardial catheter tip surrounded by air or placed over a fat tissue layer.
González‐Suárez et al. (Mon,) conducted a other in Radiofrequency cardiac ablation. Bipolar mode (BM) radiofrequency ablation vs. Unipolar mode (UM) radiofrequency ablation (sequential and simultaneous) was evaluated on Creation of transmural lesions across the interventricular septum and ventricular free wall. Bipolar mode radiofrequency ablation was more effective than unipolar mode in creating transmural lesions across ventricular sites up to 15 mm thick, except when surrounded by air or epicardial fat.