Hemolysis related to PFA: comparative study of next generation nanosecond with conventional PFA systems

Abstract 2315806, presented at Western Atrial Fibrillation Symposium 2026

Background: Hemolysis is a well-recognized consequence of microseconds pulsed field ablation (PFA), however its occurrence with nanoseconds PFA have not been determined Objectives: the aim of the study is to compare hemolysis profiles across different PFA systems.Methods: Consecutively patients with AF undergoing first-time PFA ablation with Pentaspline (Farawave, Boston Scientific), Lattice tip (sphere-9, Medtronic), or nano-PFA 360 (CellFX, Pulsebioscience) catheters. were included in this prospective analysis. Hemolysis was assessed by haptoglobin (Hp), lactate dehydrogenase (LDH), and bilirubin measured before (T1) and 24 hours after (T2) ablation. Hemolysis was defined as a >10 mg/dL decrease in Hp between T1 and T2. Significant hemolysis was defined as Hp ≤25 mg/dL.Results: 94 (63% male, mean age 58.9 ± 1.73) patients were included. No significant difference in the baseline and procedural characteristics was found between the 3 system. The catheters used were nano PFA 360, Pentaspline and Lattice tip in 30 (32%), 34 (36%) and 34 (32%) respectively. Hemolysis occurred in 88 (91.5%) of patients. Significant hemolysis was observed in 21 (70%) nano-PFA 360, 27 (79.4%) Pentaspline, and 7 (23%) Lattice tip cases (p< 0.001).Multivariable analysis showed that nano PFA 360 and Pentaspline were associated with a similarly high risk of significant hemolysis compared with Lattice tip (p< 0.001). No significant difference was observed between nano PFA 360 and Pentaspline catheter systems. Hp decrease per application was greater with nano-PFA 360 (1.93 ± 2.87 mg/dL, p = 0.52) and pentaspline (0.73 ± 0.43 mg/dL, p = 0.11) than with lattice-tip (0.04 ± 0.05 mg/dL, p = 0.43).Conclusions: Hemolysis commonly occurs across PFA procedures, irrespective of pulse duration, and is greater with single-shot than focal system.