Hemolysis and acute kidney injury following atrial fibrillation ablation via three commercially available single-shot pulse field ablation catheters

Introduction

Hemolysis related to pulsed field ablation (PFA) and its potential progression to acute kidney injury (AKI) has been reported across all available PFA technologies. Several single-shot PFA systems have recently entered clinical practice, yet comparative data on procedure-related hemolysis and renal outcomes following pulmonary vein isolation (PVI) with or without posterior wall isolation (PWI) remain limited.

Purpose

To compare the degree of hemolysis and renal effects associated with three commercially available PFA technologies.

Methods

We prospectively evaluated 450 (64.9 ± 11 years, 46.2% female, 62% paroxysmal AF) patients undergoing PVI ± PWI. Blood samples were collected before the procedure (t0) and 24 hours afterward (t1). Laboratory testing included bilirubin (total and indirect), lactate dehydrogenase (LDH), haptoglobin, plasma free hemoglobin, urea, creatinine, and estimated glomerular filtration rate (eGFR, CKD-EPI-IDMS). Patients were treated with a pentaspline catheter (PS, n = 150), a variable-loop circular catheter (VL, n = 150), or a fixed-loop circular catheter (FL, n = 150); in each group, 50% underwent PVI-only and 50% PVI+PWI. Multivariate linear regression was used to identify predictors of Δhaptoglobin.

Results

Biochemical evidence of hemolysis, characterized by increased LDH and unconjugated bilirubin and reduced haptoglobin, was observed with all systems and procedural strategies (Figure 1). PS produced a significantly greater reduction in haptoglobin (−50% in PVI-only; −71% in PVI+PWI) compared with VL (−40% in both lesion sets, p ≤ 0.001) and FL (−24% and −38%, p < 0.001). Despite these differences, post-ablation creatinine and eGFR did not significantly differ among technologies, and no clinically relevant hemolysis-related AKI occurred.

Three patients (0.67%) developed AKI stage 1 (defined as an increase in serum creatinine ≥0.3 mg/dL); however, despite the observed reduction in haptoglobin, its levels remained within the normal range in all three patients, indicating that these AKI events were not hemolysis-related.

In multivariate models, the number of PFA applications was independently associated with Δhaptoglobin in the VL and FL groups (p < 0.001), but not in the PS group (Figure 2).

Conclusions

All three PFA systems produced measurable biochemical hemolysis; however, no cases of clinically significant hemolysis-related AKI were observed. PS was associated with a larger decline in haptoglobin, potentially reflecting a greater hemolytic effect independent of the number of pulses delivered. In contrast, VL and FL demonstrated a linear relationship between pulse count and degree of hemolysis. Although these differences indicate distinct hemolytic profiles among commercially available PFA technologies, they were not clinically relevant, as renal function remained stable and no clinically meaningful hemolysis-related complications occurred.Figure1Figure2