Periprocedural Intravascular Hemolysis During Atrial Fibrillation Ablation: A Comparison of Pulsed Field With Radiofrequency Ablation

Abstract

Background Hemolysis-related renal failure has been described after pulmonary vein isolation (PVI) with pulsed-field ablation (PFA). Objectives This study sought to compare the potential for hemolysis during PVI with PFA vs radiofrequency ablation (RFA). Methods In consecutive patients, PVI was performed with PFA or RFA. Blood samples were drawn at baseline, immediately postablation, and 24 hours postablation. Using flow cytometry, the concentration of red blood cell microparticles (RBC mu) (fragments of damaged erythrocytes) in blood was assessed. Lactate dehydrogenase (LDH), haptoglobin, and indirect bilirubin were measured at baseline and 24 hours. Results Seventy patients (age: 64.7 +/- 10.2 years; 47% women; 36 [51.4%] paroxysmal atrial fibrillation) were enrolled: 47 patients were in the PFA group (22 PVI-only and 36.4 +/- 5.5 PFA applications; 25 PVI-plus, 67.3 +/- 12.4 pulsed field energy applications), and 23 patients underwent RFA. Compared to baseline, the RBC mu concentration increased similar to 12-fold postablation and returned to baseline by 24 hours in the PFA group (median: 70.8 [Q1-Q3: 51.8-102.5] vs 846.6 [Q1-Q3: 639.2-1,215.5] vs 59.3 [Q1-Q3: 42.9-86.5] RBC mu/mu L, respectively; P < 0.001); this increase was greater with PVI-plus compared to PVI-only (P = 0.007). There was also a significant, albeit substantially smaller, periprocedural increase in RBC mu with RFA (77.7 [Q1-Q3: 39.2-92.0] vs 149.6 [Q1-Q3: 106.6-180.8] vs 89.0 [Q1-Q3: 61.2-123.4] RBC mu/mu L, respectively; P < 0.001). At 24 hours with PFA, the concentration of LDH and indirect bilirubin increased, whereas haptoglobin decreased significantly (all P < 0.001). In contrast, with RFA, there were only smaller changes in LDH and haptoglobin concentrations (P = 0.03) and no change in bilirubin. Conclusions PFA was associated with significant periprocedural hemolysis. With a number of 70 PFA lesions, the likelihood of significant renal injury is uncommon.