Cardiac Troponin I kinetic after pulmonary vein isolation for atrial fibrillation ablation with pulsed-field ablation and cryo-energy

FUNDING ACKNOWLEDGEMENTS: Type of funding sources: None. BACKGROUND: Previous studies have demonstrated that cardiac biomarkers elevate after both cryoballoon (CB) and radiofrequency atrial fibrillation (AF) ablation, depending on the amount of energy delivered and the site of ablation. To date no comparison has been made between these thermal energy source and a novel non-thermal pulsed-field ablation (PFA) technology based on cells electroporation. PURPOSE: Our analysis aims to compare acute myocardial injury through cardiac troponin I variation after pulmonary vein isolation (PVI) performed with different technologies (PFA vs CB). METHODS: All consecutive patients undergoing paroxysmal AF ablation with CB and PFA at our center from July to November 2022 were included. Protocol-directed cryoablation (CBA) was delivered for 180 sec or 240 sec according to operator’s preference for isolation achieved in ≤60 sec, or 240 sec if isolation occurred >60 sec or when time to isolation was not available. A standard PFA protocol-directed PVI was applied using 2kV with eight applications per vein (four applications each in the basket and flower poses). The ablation endpoint was PVI as assessed by entrance and exit block. Pre- and post-procedure samples of cardiac troponin I (CTpI) were collected before CBA/PFA and at 24h after ablation. Only patients with normal baseline values for myocardial injury were included. RESULTS: A total of 71 patients met inclusion criteria and were included in this analysis. The CBA group consists of 50 (70%) patients and the PFA group comprises 21 (30%) patients. The number of CBA applications to reach PVI was 5.0±1.4 and the number of PFA applications to achieve PVI was 32±4. All (100%) patients were in sinus rhythm at the time of the procedure. Evaluating the kinetic of CTpI, baseline values were homogeneous between CBA and PFA groups (p=0.979) whereas CTpI values significantly rose from baseline (7±2 ng/L) to 24h (8979±3691 ng/L, p<0.0001) and were significantly different between groups after CBA/PFA (8148±3311 ng/L for CBA vs 11900±7143 ng/L for PFA, p=0.0056). PVI was achieved in all patients (100%) using only CB or PFA. No major procedure-related adverse events were reported. CONCLUSION: Our preliminary results showed that cardiac troponin I enzyme level increased after PVI by means of both cryoballoon and pulsed-field ablation and were higher after cellular electroporation by PFA than cryoablation.