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 (RBCµ) (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 RBCµ concentration increased ∼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] RBCµ/µL, 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 RBCµ 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] RBCµ/µL, 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.