Hemolysis Induced by Pulsed-Field Ablation of Atrial Arrhythmias: A Comparative Analysis of Current Systems.

Introduction Pulsed-field ablation (PFA) is an emerging technology associated with dose-dependent hemolysis as a recently recognized side effect. This study aimed to compare hemolysis levels and assess dose-dependency across three PFA systems: a pentaspline catheter (PSC), a lattice-tip focal catheter (LTFC), and a variable loop circular catheter (VLCC).Methods Patients treated for atrial arrhythmias with the LTFC (n = 29) or the VLCC (n = 30) were included from a prospective registry. A matched cohort of patients treated with the PSC (n = 28) was recruited from the same registry. Creatinine levels and markers of hemolysis were measured pre-ablation and 1 day postablation.Results Haptoglobin levels decreased significantly more with the PSC and VLCC compared to the LTFC (-0.65 [-0.76, -0.49] g/L; -0.56 [-0.78, -0.43] g/L, -0.21 [-0.32, -0.1] g/L, respectively; p < 0.001 for both). Per-application decreases in haptoglobin also differed (-17.5 [-20.38, -13.58] mg/L, -24.35 [-36.36, -17.92] mg/L, -3.61 [-5.98, -2.13] mg/L, respectively; p < 0.001 for both). There was no significant difference in haptoglobin decrease between the PSC and VLCC per procedure (p = 1.0). Haptoglobin decrease per application was significantly larger with the VLCC compared to the PSC (p = 0.0048). Per procedure LDH increase followed a similar trend (49 [18, 81.25] U/L; 14 [6, 60] U/L; 13 [-4, 46] U/L; respectively; p = 0.037). No hemolysis-related complications were observed.Conclusions Hemolysis levels vary significantly among PFA platforms. Focal PFA catheters induce less hemolysis per procedure and application compared to large-footprint catheters.