Bipolar Catheter Ablation as a Key for Successful Treatment of Intramural VentricuLar Arrhythmias: Results From the Bipolar‐Kiel Study

Unipolar catheter ablation (CA) is effective in the treatment of ventricular arrhythmias but its efficacy can be limited in eliminating intramural arrhythmic origins. Bipolar ablation has emerged as a bail-out strategy. However, currently, it is being primarily utilized after a failed ablation attempt. The aim of this study is to assess the safety and efficacy of endocardial and/or epicardial bipolar catheter ablation in patients with ventricular arrhythmias within their first procedure or after a previously failed ablation attempt. Patients who underwent bipolar CA between September 2022 and February 2025 were included. A total of 21 bipolar ablation procedures were performed in 19 patients (median age 66 ± 11, 11% female, median ejection fraction 42% ± 16%). In total, 16 procedures were performed due to ventricular tachycardia (VT) or VT storm, five procedures were performed due to symptomatic premature ventricular contractions (PVC). In 48% of all cases, ablation was performed within the patient's first procedure. The interventricular septum was the most common site of bipolar ablation (11/21), followed by epi-endocardial bipolar ablation procedures (9/21) and the papillary muscle (1/21). Bipolar ablation was successful in 17/21 patients. In one patient, AV block occurred after bipolar ablation. During a median follow-up time of 12 ± 6 months, four patients with initially acute procedural success experienced recurrence of a ventricular arrhythmia. Bipolar catheter ablation is an effective tool for arrhythmias with an intramural origin. It is shown to be safe with a high acute success rate in patients undergoing their first or redo procedure for VT or PVC.