Does hemolysis matter after pulsed field ablation for atrial fibrillation? Insights from the Best Ablate Registry

Pulsed field ablation (PFA) has emerged as a novel nonthermal modality for atrial fibrillation (AF) ablation, offering tissue selectivity and procedural safety. However, emerging data have raised concerns about hemolysis-related biomarker shifts and potential renal failure after PFA.

This study aimed to evaluate biomarker-defined hemolysis and the incidence of acute renal injury after PFA in patients undergoing AF.

In this prospective observational study, 84 patients with paroxysmal or persistent AF undergoing PFA using either the Affera or PulseSelect system were enrolled. Paired venous blood samples were obtained before and 24 hours after the procedure. Biomarkers of hemolysis (lactate dehydrogenase [LDH], haptoglobin, hemoglobin, and bilirubin), renal function parameters (serum creatinine, urea, and electrolytes), and cardiac enzymes (high-sensitivity cardiac troponin, N-terminal pro-B-type natriuretic peptide) were systematically analyzed. Clinically significant hemolysis was defined as a postprocedural haptoglobin concentration of <0.04 g/L or a combination of indirect bilirubin of >1.5 times baseline and LDH more than twice baseline. Multivariable linear regression and mediation analyses were performed to identify procedural predictors of biomarker changes and explore the potential mediating role of myocardial injury.

Significant postprocedural changes were observed in biomarkers of hemolysis, including a reduction in haptoglobin (-0.17 ± 0.21 g/L; P < .001), an increase in LDH (+43.32 ± 79.98 U/L; P < .001), and bilirubin concentrations (P < .001). No patient met the predefined criteria for clinically significant hemolysis. Acute kidney injury stage 1, without oliguria, was observed in 3 patients (3.6%). Cardiac biomarker analysis revealed a substantial rise in high-sensitivity troponin (+1151.7 ± 750.8 ng/L; P < .001), whereas N-terminal pro-B-type natriuretic peptide decreased significantly after ablation (P < .001). The total number of PFA applications independently predicted changes in both LDH and haptoglobin.

In our study, PFA for AF was associated with an increase in hemolytic parameters, without significant short-term renal impact or occurrence of clinically significant hemolysis. Hemolysis seems to be influenced by both lesion burden and myocardial injury, highlighting the need for further investigation into the long-term clinical relevance of biomarker-defined hemolysis in PFA-treated patients.