Intravascular hemolysis after pulsed field ablation for atrial fibrillation: A comparative analysis of 3 systems

Background Intravascular hemolysis following pulsed-field ablation (PFA) for atrial fibrillation (AF) contributes to renal dysfunction; however, the extent and clinical relevance may differ depending on the ablation system used. Objective To compare the extent of intravascular hemolysis across three pulmonary vein isolation (PVI) systems in patients with AF. Methods This single-center study included consecutive patients who underwent PVI using one of the three PFA systems: FARAWAVE (n=29), VARIPULSE (n=30), or PulseSelect (n=32). Haptoglobin levels and myocardial injury biomarkers were evaluated at three time points: before the procedure (T1), immediately after the procedure (T2), and next day after the procedure (T3). Results PVI was performed using standard application counts for each system (median [IQR]: FARAWAVE 34 [33, 37], VARIPULSE 18 [17, 20], and PulseSelect 48 [42, 49]; P<0.001). Haptoglobin levels (mg/dL) significantly decreased from baseline at T2 and T3 in all groups, with a more pronounced decline observed in the FARAWAVE group at T3 than in the PulseSelect (25 [16, 50] vs. 60 [34, 86], P<0.01). Lactate dehydrogenase levels increased significantly at T2 in the FARAWAVE and VARIPULSE groups, but not in the PulseSelect group. Other myocardial biomarkers (creatine kinase and aspartate aminotransferase) showed comparable increases across systems. No clinically significant renal impairment or acute kidney injury occurred in any of the groups. Conclusion Intravascular hemolysis is frequent yet generally subclinical after PFA. FARAWAVE exhibited higher hemolysis than PulseSelect, while VARIPULSE demonstrated an intermediate profile. Despite these differences, no clinically meaningful renal impairment was observed under standard application counts.