Atrial tachycardia

From IKE

Atrial tachycardia is a type of arrhythmia in which the atria of the heart beat too rapidly. This type of tachycardia's focus is above the AV node. Though it may be difficult to see, a P wave precedes each QRS complex. A carotid sinus massage or other vagal maneuvers could cause 2:1 or 3:1 conduction to ventricles.