Catheter Mapping and Ablation of Right Ventricular Outflow Tract Ventricular Tachycardia

Idiopathic Outflow Tract Tachycardias

“…ECG analysis can help to localize the possible site of OT-VT [3]. Activation and pace mapping are the two main mapping methods which are used to guide the ablation.…”

“…Activation and pace mapping are the two main mapping methods which are used to guide the ablation. The site of origin of OT-VT is usually very well defined, discrete, and easy to find (in a stepwise anatomic approach guided by the ECG morphology) and, therefore, normally treated with radiofrequency catheter ablation guided by endocardial activation or pace mapping in a stepwise approach (Figure 3) [2,3,23,28]. Local bipolar ventricular electrogram at the site of successful catheter ablation is usually 10-60 ms earlier than the onset of the surface QRS complex at the site of successful ablation.…”

“…However, this should exactly reproduce the twelve-lead ECG of the clinical QRS complex [3]. However, it should be mentioned that recent data suggest that the spatial resolution of pace mapping in the OT-VT is limited and exact (12/12) matches usually could be achieved from multiple sites in these patients, some at sites ≥ 2 cm away from the site of origin [2][3][4]. Having the limitations of activation and pace mapping in mind, ablation can be guided by electroanatomic mapping systems in difficult cases (Figure 4) [2-4, 28, 37-40].…”

“…Outflow tract ventricular tachycardias (OT-VTs) are the most common form of idiopathic VTs which accounts for nearly 10% of all patients referred for evaluation of VT [1][2][3]. In > 80-90% of cases OT-VT originates from the right ventricular outflow tract, however, other origins like the septum, the left ventricular outflow tract, the pulmonary artery, the aortic sinus of Valsalva, the area near the His bundle, and the epicardial surface of the ventricles have been described [4][5][6][7][8][9][10][11][12].…”

Effect of Limb Lead Electrodes Location on ECG and Localization of Idiopathic Outflow Tract Tachycardia: A Prospective Study

“…Idiopathic ventricular tachycardia (VT) accounts for approximately 10% of all ventricular tachycardias 1–3 . Idiopathic VT is defined when structural heart diseases have been ruled out as the underlying etiology.…”