Table 1: Electrocardiographic Morphology of Outflow Tract Ventricular Tachycardias.
| Site of Origin | Lead V1 | Precordial Transition | Lead I | Additional |
|---|---|---|---|---|
| RVOT free wall | - | ≥V4 | Site 1 + Site 2 +/- Site 3 - |
Notching in inferior leads |
| Septal RVOT | - | V3 or V4 | Site 1 + Site 2 +/- Site 3 - |
|
| Right coronary cusp | - | V2 or V3 | + | Notching in downstroke of V1 suggests junction of RCC and LCC |
| Left ventricular summit | - | V2 or V3 | - or +/- | Pattern break in V2 with more net negativity than V1 or V3 |
| Left coronary cusp | +/- | + throughout or V2 | - | M or W configuration common in V1 |
| Aortomitral continuity | qR | + throughout | +/- | |
| Superior mitral annulus | + | + throughout | Septum + lateral - |
All outflow tract ventricular tachycardias are positive in the inferior leads (II, III and aVF). + = positive. +/-; isoelectric or biphasic; - = negative; RVOT = right ventricular outflow tract. Adapted from: Liang et al. 2015.1 Used with permission from Springer Nature.