Acute kidney injury related to pulsed field ablation of atrial fibrillation: Protective role of the protocol-based hydration regimen

BACKGROUND: Acute kidney injury (AKI) because of hemolysis is a potential complication of pulsed field ablation (PFA) of atrial fibrillation (AF). OBJECTIVE: This study aimed to assess the incidence and risk factors of AKI and the protective effect of a protocol-based hydration regimen in an unselected patient cohort undergoing PFA with a pentaspline catheter. METHODS: Data from 501 consecutive patients treated with PFA were prospectively analyzed. The first 232 (46.3%) procedures were performed without hydration, whereas the subsequent 269 (53.7%) included a predefined hydration protocol (≥2000 mL fluid). RESULTS: AKI occurred in 6.4% (32 of 501) of patients (3.8% AKI 1, 1.4% AKI 2, 1.2% AKI 3). Patients with AKI had a significantly higher mean number of PF applications (105.1 ± 26.2 vs 73.4 ± 22.2, P < .001). Multivariable analysis identified chronic kidney disease (CKD) (odds ratio [OR] 3.29, 95% confidence interval [CI] 1.45-7.46, P = .005), extensive left atrial ablation (OR 6.67, 95% CI 1.47-63.79, P = .01), and a higher number of PF applications (OR 1.37 per 10 applications, 95% CI 1.17-1.61, P < .001) as AKI risk factors, whereas hydration was protective (OR 0.33; 95% CI 0.14-0.75, P = .008). Predictive modeling for AKI risk defined a 5% risk at 118 pulses in non-CKD and at 78 pulses in patients with CKD. CONCLUSION: AKI after PFA occurs in approximately 6.4% of patients, predominantly mild cases. The risk increases with CKD, extensive ablation, and high PF pulse counts. Protocol-driven peri-procedural hydration substantially reduces the risk of AKI.