First clinical data on artificial intelligence-guided catheter ablation in long-standing persistent atrial fibrillation.

INTRODUCTION: Despite advanced ablation strategies and major technological improvements, treatment of persistent atrial fibrillation (AF) remains challenging and the underlying pathophysiology is not fully understood. This study analyzed the multiple procedure outcome and safety of catheter ablation of spatiotemporal dispersions (DISPERS) detected by artificial intelligence (AI)-guided software in patients with long-standing persistent AF. METHODS AND RESULTS: The Volta VX1 software was used for 50 consecutive patients undergoing catheter ablation for persistent AF. First, high-density mapping (78% biatrial) with a multipolar mapping catheter was performed. In addition to pulmonary vein isolation (PVI), ablation of DISPERS was performed aiming at homogenizing, dissecting, isolating, or connecting DISPERS areas to nonconducting anatomical structures. Follow-up contained regular visits at our outpatient clinic at 1, 3, 6, and 12 months including 7-day Holter electrocardiograms. Patients were mainly suffering from long-standing persistent AF (mean AF duration 50.30 ± 54.28 months). Following PVI, ablation of left atrial and right atrial DISPERS areas led to AF cycle length prolongation (mean of 162.0 ± 16.6 to 202.2 ± 21.6 ms after) and AF termination to atrial tachycardia (AT) or sinus rhythm (SR) in 12 patients (24%). No stroke or pericardial effusion occurred; major groin complications (pseudoaneurysm n = 1, atrioventricular fistula n = 1) were detected in two patients. After a blanking period of 6 weeks, recurrence of any atrial arrhythmia was documented in 26 patients (52%). The majority of patients presented with organized AT (n = 15) while AF was present in n = 9 patients and AT/AF was observed in n = 2 patients. Twenty-two patients underwent reablation. During a mean follow-up of 363.14 ± 187.42 days and after an average of 1.46 ± 0.68 procedures, 82% of patients remained in stable SR. CONCLUSION: DISPERS-guided ablation using machine learning software (the Volta VX1 software) in addition to PVI in long-standing persistent AF ablation resulted in high long-term success rates regarding AF and AT elimination. Most arrhythmia recurrences were reentrant AT. After a total of 1.46 ± 0.68 procedures, freedom from AF/AT was 82%. Despite prolonged procedure times complication rates were low. Randomized studies are necessary to evaluate long-term efficacy of dispersion-guided ablation using AI.

Focal pulsed field ablation in complex atrial tachycardia: First clinical experience and 1- year outcome.

BACKGROUND: Pulsed-field ablation (PFA) has become increasingly important in the treatment of cardiac arrhythmias. In addition to single-shot devices mainly used for pulmonary vein isolation, focal PFA may provide a treatment option increasing the versatility of the technique. OBJECTIVE: The study objective was to provide data on feasibility, safety and long-term outcome of focal PFA for the ablation of complex atrial tachycardia (AT). METHODS: All consecutive patients (n=34) with complex AT treated at our department between 2022 and 2023 with a focal PFA system (CENTAURI™, Galvanize therapeutics, San Carlos, USA) were included. The majority of patients (32/34 pts) had undergone at least one prior radiofrequency ablation. Established contact-force sensing catheters were used for PFA application in combination with a PFA generator. Pulse electric field (PEF) trains were conducted in a R-wave triggered manner. RESULTS: Acute procedural success was accomplished in all patients. PFA included creation of 51 linear lesions and (re)isolation of 12 pulmonary veins. Mean procedure duration was 102.7 ± 30.3 min, with a LA dwell time of 75.0 ± 24.7 min. Mean fluoroscopy duration was 8.7 ± 5.3 min. No complications occurred. After a mean follow-up of 340.9 ± 130.1 days, recurrence of any AT occurred in 15 patients (44.1%). During 9 reablations, 3 gaps in previously created linear lesions were detected whereas the majority of recurrences (n=6) was not related to previous PFA lesion creation. CONCLUSION: Focal pulsed-field ablation of complex AT substrates was safe and efficient. Acute procedural success was 100%; after one year, the majority of patients were in sinus rhythm. A minority of recurrences was caused by insufficient PFA lesion creation.

Renal function and periprocedural complications in patients undergoing left atrial catheter ablation: A comparison between uninterrupted direct oral anticoagulants and phenprocoumon administration.

BACKGROUND: Data regarding uninterrupted oral anticoagulation in patients with chronic kidney disease (CKD) during catheter ablation for left atrial arrhythmias is limited. This study aimed to evaluate the safety and efficacy of periprocedural uninterrupted direct oral anticoagulants (DOAC) compared with uninterrupted phenprocoumon in patients with CKD undergoing left atrial catheter ablation. METHODS AND RESULTS: We conducted a retrospective single-center study of patients who underwent left atrial catheter ablation between 2016 and 2019 with underlying chronic kidney disease (glomerular filtration rate (GFR) between 15 and 45 ml/min). The primary objective of this study was to investigate whether direct oral anticoagulant (DOAC) therapy or warfarin presents a superior safety profile in patients with chronic kidney disease (CKD) undergoing left atrial catheter ablation. We compared periprocedural complications (arteriovenous fistula, aneurysm, significant hematoma (> 5 cm)) and/or bleeding (drop in hemoglobin of >2 g/dl, pericardial effusion, retroperitoneal bleeding, other bleeding, stroke) between patients receiving either uninterrupted DOAC or warfarin therapy. Secondary analysis included patient baseline characteristics as well as procedural data. A total of 188 patients (female n = 108 (57%), mean age 75.3 ± 8.1 years, mean GFR 36.8 ± 6 ml/min) were included in this study. Underlying arrhythmias were atrial fibrillation (n = 104, 55.3%) and atypical atrial flutter (n = 84, 44.7%). Of these, n = 132 patients (70%) were under a DOAC medication, and n = 56 (30%) were under phenprocoumon. Major groin complications including pseudoaneurysm and/or AV fistula occurred in 8.9% of patients in the phenprocoumon group vs. 11.3% of patients in the DOAC group, which was not statistically significant (p = 0.62). Incidence of cardiac tamponade (2.3% vs. 0%; p = 0.55) and stroke (0% vs. 0%) were low in both DOAC and phenprocoumon groups with similar post-procedural drops in hemoglobin levels (1.1±1 g/dl vs 1.1±0.9 g/dl; p = 0.71). CONCLUSION: The type of anticoagulation had no significant influence on bleeding or thromboembolic events as well as groin complications in this retrospective study. Despite observing an increased rate of groin complications, the uninterrupted use of DOAC or phenprocoumon during left atrial catheter ablation in patients with CKD appears to be feasible and effective.