Myocardial injury with extensive versus standard pulsed field ablation using a pentaspline catheter for the treatment of atrial fibrillation

Background Pulsed-field ablation (PFA) has emerged as a safe modality for the treatment of atrial fibrillation (AF), offering a mainly non-thermal approach for ablation. While myocardial injury after catheter ablation has been described using thermal modalities, little is known about the extent of myocardial injury using PFA. Purpose To assess the extent of myocardial injury after PFA using a pentaspline catheter and varying total number of applications. Methods This study enrolled consecutive patients undergoing PFA for the treatment of AF using a pentaspline catheter system (PCS, FARAPULSE, Boston Scientific) between January 2022 and January 2025 at a tertiary referral center. Patients were divided into two groups, comparing a standard (total applications <40) and an extensive (total applications ≥40) ablation protocol. High-sensitivity cardiac Troponin T (hs-cTnT) levels were measured one day before and one day after PFA. Results Of 770 patients (age 67 years [60-73], 31% female) undergoing PFA, 524 patients (68%) were in the standard application and 246 (32%) in the extensive application group. Patients in the extensive application group were more often in persistent AF (61% vs. 46%; p <0.001) and demonstrated larger left atrial volume index (42 ml/m2 [33-51]) compared to the standard application group (37 ml/m2 [30-45]; p <0.001). The median number of applications was 50 [46 - 61] in the extensive group and 32 [20 - 34] in the standard group (<0.001). Pre-interventional median hs-cTnT was similar in both groups (extensive 11 [8-16] ng/l, standard 10 [7-15] ng/l; p 0.247). In the extensive application group, post-interventional median hs-cTnT levels the following day were significantly higher (1479 [1000-2047] ng/l) compared to the standard application group (1169 [807-1834] ng/l; p <0.001, Figure). Conclusion In patients undergoing PFA, a higher total number of applications is associated with a substantially larger myocardial injury, reflected by higher median hs-cTnT levels. Further studies are necessary to investigate the correlation between post-interventional myocardial injury and long-term clinical outcomes.