Multipolar Ablation Using Mapping Electrodes: A Novel Approach to Intramural Arrhythmia Substrates.

Intramural ventricular arrhythmias are challenging to treat. Adjunctive techniques such as bipolar ablation, ethanol injection, use of a needle catheter, or surgery have been described. These are often not readily available. This is a case report of a patient with refractory intramural ventricular arrhythmia that was ablated by incorporating electrodes of a mapping catheter into the ablation circuit. The results of ex vivo experiments to determine the characteristics of multipolar ablation lesions using different ablation settings are reported. The feasibility of generating transmural lesions with multipolar ablation in vivo in a porcine model was tested.