Hemolysis and kidney injury after catheter ablation for atrial fibrillation: Microsecond vs nanosecond pulsed field ablation.

BACKGROUND

Microsecond pulsed field ablation (PFA) (microPFA) has been associated with postablation hemolysis, whereas evidence for the use of nanosecond PFA (nanoPFA) remains limited.

OBJECTIVE

This study aimed to compare hemolysis and acute kidney injury (AKI) after microPFA, nanoPFA, and radiofrequency ablation (RFA).

METHODS

We included 323 patients who underwent atrial fibrillation ablation at a high-volume Chinese center, including microPFA (n = 186), nanoPFA (n = 65), or RFA (n = 72). Pulmonary vein isolation was performed with or without additional ablation. Hemolysis and renal biomarkers were measured at baseline, procedure end, and 24 hours after the procedure.

RESULTS

PFA produced obvious hemolysis, which was not observed with RFA. Postablation bilirubin, lactate dehydrogenase (LDH), and free hemoglobin increased and haptoglobin decreased with PFA. LDH (229.0 ± 50.6 vs 198.4 ± 33.8 IU/L; P < .001) and free hemoglobin levels (289.3 ± 45.1 vs 263.7 ± 55.0 ng/mL; P = .043) were higher with microPFA than with nanoPFA after multivariable adjustment. Hemoglobin decline and hemoglobin drop of >20 g/L occurred more often after microPFA (44.1% and 58.1%) than after RFA (22.2% and 27.8%) and nanoPFA (18.5% and 20.0%). AKI was uncommon (microPFA 3; nanoPFA 1; RFA 0). In microPFA, hemolysis scaled with delivery number (LDH ratio r = 0.26; 95% confidence interval 0.10-0.40; bilirubin ratio r = 0.15; 95% confidence interval 0-0.29), whereas no dose-dependent association was detected with nanoPFA.

CONCLUSION

PFA for atrial fibrillation typically induced hemolysis; however, the application-related dose effect was observed in microPFA, but not in nanoPFA. NanoPFA was associated with lower hemolysis indices, whereas severe anemia and AKI may be rare. Larger studies are needed to confirm modality differences, define clinical impact, and optimize application titration.