Impact of Pulse Field Ablation on Hemolysis Markers: A Single-Center Experience.

BACKGROUND

Pulse field ablation (PFA) has gained attention as an alternative modality for ablation of atrial fibrillation (AF) due to its favorable safety profile compared with thermal ablation. However, hemolysis has emerged as a unique concern with PFA, yet the risk factors underlying its development and the extent to which it translates into renal complications remain poorly defined.

METHODS

We performed a retrospective cohort study of patients with atrial fibrillation who underwent PFA at our health system between June 2024 and May 2025. Postprocedural hemolysis was assessed using plasma-free hemoglobin (Hb) levels, with patients stratified into high (> 30 mg/dL) and normal/low (≤ 30 mg/dL) groups. Baseline characteristics, procedural details, and renal outcomes were compared between groups, and multivariable analyses were conducted to identify independent risk factors associated with hemolysis.

RESULTS

A total of 232 patients (FARAPULSE [Manufacturer 1 PFA system] in 173 patients [74.6%]; PulseSelect [Manufacturer 2 system] in 59 patients [25.4%]) underwent PFA (mean age 67.5 ± 9.6, 34.1% female), of whom 109 (47.0%) developed high postprocedural plasma-free Hb (> 30 mg/dL). Baseline demographics were similar between groups, but patients with high free Hb were more often treated with the Manufacturer 1 PFA system (91.7% vs. 59.3%, p < 0.01), underwent PVI with additional ablation (73.4% vs. 45.5%, p < 0.01), and received a greater number of applications (63.2 ± 14.9 vs. 51.1 ± 11.5, p < 0.01). On multivariable analysis, independent risk factors associated with hemolysis included use of the Manufacturer 1 system (aOR 6.67, 95% CI 2.94-16.47), total applications > 59 (aOR 4.25, 95% CI 2.04-9.19), and higher preprocedural hemoglobin level (aOR 1.52, 95% CI 1.19-1.97). The rate of AKI was low and similar between the two groups (0.9% vs. 0.8%, p = 1.00). None of the patients required renal replacement therapy.

CONCLUSION

Our real-world study, following the commercial approval of PFA systems, showed that 47% of patients developed subclinical hemolysis after PFA, with no actionable clinical outcomes.