Endocardial noncontact activation mapping of idiopathic left ventricular tachycardia

Idiopathic left ventricular tachycardia with a right bundle, left-axis devi ation is thought to originate from posterior fascicles. Recently, there has been considerable interest in the anatomic and mechanistic basis of this a rrhythmia. We report our experience with a 26-year-old man in whom new nonc ontact mapping technology was used to acquire detailed data from the left v entricle, identify the mid-diastolic potential and part of the ventricular tachycardia circuit, and perform successful ablation. This information help ed define the physiologic aspects of this unique tachycardia.