Hemolysis and Renal Effects Across Pulsed Field Ablation Systems in Atrial Fibrillation

INTRODUCTION: Pulsed field ablation (PFA) is a non-thermal energy modality for ablation of atrial fibrillation (AF). Although PFA has demonstrated an excellent overall safety profile, increasing evidence suggests an association with intravascular hemolysis, and acute kidney injury (AKI). However, the extent of hemolysis across different PFA catheters remains poorly characterized and warrants further investigation. METHODS: We prospectively enrolled 239 patients undergoing AF ablation using the pentaspline (n = 107), balloon-in-basket (n = 71), or lattice-tip (n = 61) catheter. Laboratory markers of hemolysis, myocardial injury, renal function and haemoglobin were collected pre- and 24 h post-procedure. RESULTS: Significant haptoglobin depletion was observed exclusively with pentaspline, [pre 99.8 mg/dL (70.2-122) vs. post 55.7 mg/dL (23.2-91.8); p < 0.001] Reductions with the lattice-tip (p = 0.074) and the balloon-in-basket (p = 0.201) catheter did not reach statistical significance. AKI was only observed with the pentaspline catheter (pentaspline: 4.9%; balloon-in-basket: 0.0%; lattice tip: 0.0%; p = 0.020).Myocardial markers increased across all groups, but significantly higher in pentaspline and balloon-in-basket (p = n.s.) vs lattice-tip (p < 0.001 vs pentaspline, p < 0.001 vs ballon in basket). CONCLUSIONS: In this large cohort, contemporary PFA systems appear safe but catheter design influences the extent of hemolysis, AKI, and myocardial injury. The pentaspline catheter was associated with the greatest hemolytic effect and higher transient AKI, without clinically relevant reductions in hemoglobin or persistent renal impairment. Higher levels of myocardial injury in the pentaspline and balloon-in-basket groups correspond to the larger lesion footprints of these devices.Word counting abstract: 234.