Evaluation of the risk of hemolysis using the circular array pulsed field ablation catheter in the management of atrial fibrillation

<h2>Abstract</h2><h3>Background</h3> Procedure-related complications such as intravascular hemolysis have been reported with Pulsed Field Ablation (PFA). However, data for the circular array catheter are limited. <h3>Objective</h3> To quantify intravascular hemolysis after atrial fibrillation (AF) ablation with the circular array catheter and compare outcomes with alternate PFA systems. <h3>Methods</h3> Consecutive patients undergoing AF ablation with PFA at a single center underwent routine post-ablation bloodwork collection of hemolysis and renal markers. Data was evaluated according to AF ablation strategy (pulmonary vein isolation [PVI] versus PVI + posterior wall isolation [PWI]) and between PFA technologies. Predictors of significant hemolysis (plasma-free hemoglobin [fHb>0.5 g/L]) were assessed using logistic regression. <h3>Results</h3> A total of 224 patients (209 Circular array; 15 Pentaspline) were evaluated. The circular array catheter resulted in mild hemolysis (median fHb 0.38 g/dL). The fHb was higher with PVI + PWI versus PVI alone (0.42 g/dL vs 0.32 g/dL, p < 0.001) and correlated moderately with lesion number (r = 0.32, p < 0.001). Compared with the circular array catheter, ablation using the pentaspline resulted in significantly higher fHb (0.38 g/dL vs 0.76 g/dL, p < 0.001). No patient required blood transfusion or dialysis. Multivariable logistic regression identified lesion burden (OR:1.04 per lesion, 95% CI: 1.01–1.06, p=0.003), pentaspline catheter (OR: 10, 95% CI: 2.57-39.56, p=0.001), and additional ablation, such as posterior wall, (OR: 2.41, 95% CI: 0.98–5.94, p=0.056) as predictors of hemolysis. <h3>Conclusion</h3> The circular array catheter is associated with mild, lesion number-dependent hemolysis and demonstrates a more favorable hemolytic profile compared with the pentaspline catheter. Since haptoglobin, renal parameters take hours to change, we cannot estimate the effects on these parameters or clinical relevance from an immediate blood draw.