Evaluation of hemolytic and renal safety post-pulmonary vein isolation using a next-generation balloon-in-basket PFA system

Abstract Background Advances in cardiac ablation, particularly pulsed field ablation (PFA), have expanded treatment options for atrial fibrillation through pulmonary vein isolation (PVI). Concerns have emerged regarding adverse effects, including hemolysis and acute kidney injury, associated with PFA. Purpose This study evaluates the impact of a novel balloon-in-basket, 3D-integrated PFA system on hemolysis, renal function, and inflammation markers following PVI. Methods This analysis included 27 patients from the 150-patient VOLT CE Mark Study, a prospective, multi-center, single-arm pre-market trial. Patients with symptomatic paroxysmal or persistent AF received de-novo AF ablation using the balloon-in-basket PFA system, performing only PVI as per protocol. Blood samples were collected pre- and post-procedure (day one) to measure markers of hemolysis (LDH, haptoglobin, bilirubin), renal function (GFR), myocardial injury (troponin, myoglobin), and inflammation (CRP, leukocytes). Normality was assessed with the Shapiro-Wilk test, and data were analyzed using paired-samples t-tests or Wilcoxon signed-rank tests based on distribution. Results The subset included 27 patients (41% female; mean age 66 ± 11 years; BMI 28 ± 4 kg/m²; CHA2DS2-VASc score 2.1 ± 1.4). Mean procedure and fluoroscopy times were 74 ± 10 minutes and 9.4 ± 3.4 minutes, respectively, with contrast dye use averaging 49 ± 7 ml. On average, patients received 16.8 ± 1.8 PFA applications, or 4.2 ± 0.82 per PV. Comparison of pre- and post-procedure blood samples showed significant changes in hemolysis biomarkers: LDH from 218 ± 47 U/l to 269 ± 28 U/l (p < 0.0001), haptoglobin from 1.2 ± 0.5 g/l to 1.0 ± 0.5 g/l (p = 0.0104), and bilirubin from 10.1 ± 5.7 µmol/l to 13.9 ± 9.3 µmol/l (p = 0.0140). All biomarkers remained within normal laboratory range except post-procedure LDH. Renal function remained stable (GFR pre-ablation 74.6 ± 18.6 ml/min vs. post-ablation 74.7 ± 17.6 ml/min, p = 0.9238). Post-ablation, troponin T rose from 11.2 ± 8.3 ng/l to 1737 ± 805 ng/l, indicating myocardial injury. Inflammatory markers also rose, with CRP increasing from 1.48 [1.08; 2.50] mg/l to 9.29 [3.63; 10.95] mg/l (p <0.0001) and leukocyte count showing a significant increase from 7.5 ± 2.4 × 109/l to 8.2 ± 2.2 × 109/l (p = 0.034). No acute periprocedural or postprocedural hemolytic or renal complications were observed. Conclusion Use of the balloon-in-basket, 3D-integrated PFA system for PVI was associated with measurable myocardial injury and inflammatory markers post-procedure without clinically relevant haemolysis or renal function impairment. These findings highlight the need for awareness of hemolytic and inflammatory responses following PFA. Further studies with larger samples are warranted to validate these observations and refine PFA safety profiles in AF ablation.