Ablation strategies for intramural ventricular arrhythmias.

Intramural origin of ventricular arrhythmias is one of the reasons for failure of catheter ablation, especially in nonischemic substrates. Conventional unipolar ablation has limited efficacy for the creation of deep transmural lesions in the ventricular myocardium, and alternative ablation strategies have been developed to overcome this problem. These novel approaches include simultaneous unipolar ablation, bipolar ablation, use of low-ionic irrigant solution, needle ablation, and ethanol ablation. This review provides an overview of each one of these techniques, including their main advantages and limitations.