What is the QRS duration characteristic of Ventricular Tachycardia (V Tach)?

The characteristic QRS duration in Ventricular Tachycardia (V Tach) is wider than 0.12 seconds. This wide QRS complex is due to the abnormal electrical activity originating in the ventricles, which results in conduction that is less coordinated compared to normal sinus rhythm. In healthy hearts, QRS complexes arise from the coordinated depolarization of the ventricles, leading to narrow complexes. However, in V Tach, the ventricular depolarization is typically prolonged because it often follows a different conduction pathway that bypasses the normal conduction system, such as through a single ventricle or through re-entrant circuits. This conduction delay is what leads to the wide QRS complexes observed on the ECG.

Other options refer to normal or absent QRS appearances that are not characteristic of V Tach. The presence of narrow complexes would indicate a different type of tachycardia, usually originating from the atria or involving intact conduction pathways. Therefore, understanding the significance of the QRS width helps in differentiating V Tach from other forms of tachycardia.