Cavotricuspid Isthmus Line with a Variable-Loop Biphasic Circular Pulsed Field Ablation Catheter Integrated with a 3-Dimensional Mapping System - A Case Report

Background: Pulsed field ablation (PFA) minimizes the risk of esophageal injury, pulmonary vein stenosis, and permanent phrenic nerve damage. However, when PFA is applied near coronary arteries, it has been associated with the induction of coronary vasospasm, which is typically asymptomatic but occasionally results in ventricular arrhythmias. Pre-treatment strategy with intravenous nitroglycerin can significantly reduce the occurrence of this complication. Case Presentation: A 79-year-old male with cavotricuspid isthmus (CTI)-dependent atrial flutter and atrial fibrillation underwent catheter ablation after antiarrhythmic therapy failure. Following pulmonary vein and posterior wall isolation using a novel variable-loop biphasic circular pulsed field ablation (PFA) catheter integrated with a 3D mapping system (VARIPULSE catheter, CARTO mapping system, Johnson and Johnson, USA), CTI ablation was performed with the same system. Twenty-one applications resulted in sinus rhythm restoration and confirmed bidirectional block, with no complications. Conclusion: To our knowledge, this is the first real-world reported case of CTI-dependent atrial flutter successfully treated with the mapping-integrated PFA system, with clinical and rhythm follow-up extending to 6 months. Further studies are needed to assess its role in non-pulmonary vein ablation.