Ventricular tachycardia is a specific kind of tachyarrhythmia. During VT, the heart does not pump blood as efficiently as it does during a normal sinus rhythm.
Rapid contractions prevent the ventricles from filling completely with blood between beats.
The result is less blood flow throughout the body. Not all tachycardias are abnormal conditions. Our hearts beat rapidly in response to exercise or anxiety. During these times, the electrical signals and rhythmic beats follow the same cycle as a resting heart only at a much faster rate. But certain conditions can interrupt this normal cycle, causing a rapid heartbeat.