Comparative analysis of hemolysis incidence across three different pulsed field ablation systems

Abstract Background Pulsed-field ablation (PFA) is associated with a risk of hemolysis; however, the differences among three single-shot PFA systems remain unclear. Objective This study aimed to examine the differences in hemolysis among three PFA systems. Methods We assessed changes in hemolytic, myocardial, and renal biomarkers at baseline and 24-h post-ablation in 131 patients with atrial fibrillation treated with three PFA systems (VARIPULSE, n=26; PulseSelect, n=62; FARAPULSE, n=43), as well as in 23 patients undergoing radiofrequency ablation (RFA; control) and eight patients without ablation (non-ablation control). Results Baseline characteristics were comparable across the groups. Haptoglobin levels decreased from 97.3±52.1 to 49.9±40.1 in the VARIPULSE group, 96.7±41.9 to 53.5±31.2 in the PulseSelect group, and 90.6±43.8 to 27.3±18.6 in the FARAPULSE group (all p<0.001). Compared to the control group, both hemolysis and myocardial injury were more pronounced in the PFA groups, with the greatest severity observed in the FARAPULSE group. No significant deterioration in renal function was observed in any group post-ablation; however, two cases of stage 1 acute kidney injury occurred in the FARAPULSE group, both of which fully resolved with hydration. Post-ablation haptoglobin levels exhibited a significant negative correlation with the number of applications across all PFA groups. Multivariate regression analysis identified the application ratio (total number of applications/manufacturer's recommended applications) and body mass index as independent predictors of reduced haptoglobin levels. Conclusions Intravascular hemolysis is a pertinent concern following PFA and is associated with the number of applications and body mass index, with potential differences across the three PFA systems.