Ablation of idiopathic ventricular tachycardia by bipolar radiofrequency current application between the left aortic sinus and the left ventricle

Background Failure to ablate idiopathic ventricular outflow tract tachycard ia by radiofrequency current is not uncommon and suggests that non-standard approaches may be required to map and suppress idiopathic ventricular tach yarrhythmias in some patients. Methods and Results Left and right ventricular activation and pace mapping proved inadequate for radiofrequency application in a patient with idiopath ic ventricular outflow tract tachycardia. Presystolic activity was recorded at the left aortic sinus of Valsalva, and the QRS complex recorded at this location during pacing showed few differences compared with that recorded during tachycardia. Radiofrequency current application at this site transie ntly suppressed the tachycardia. Following new mapping of the Left ventricl e outflow tract, radiofrequency application just below the aortic valve in close proximity to the previous aortic application site transiently abolish ed the arrhythmia. Finally, bipolar radiofrequency application between the distal electrode of the aortic catheter and the distal electrode of a secon d catheter placed in the left ventricular subaortic area permanently suppre ssed the tachycardia. Conclusion Bipolar radiofrequency application between the aortic sinus of V alsalva and the left ventricle could be an alternative approach in occasion al patients with idiopathic ventricular outflow tract tachycardia resistant to conventional left ventricular and aortic root unipolar radiofrequency a pplication. (Europace 2000; 2: 350-354) (C) 2000 The European Society of Ca rdiology.