Cardiac Arrhythmias - Part III Narrow Complex Tachycardia.

Narrow complex tachycardia usually refers to an abnormality of cardiac rhythm involving the tissues of the sinus node, atrial tissue, the atrioventricular node or an accessory atrioventricular communication. Although atrial fibrillation is the most common supraventricular arrhythmia, the term "supraventricular tachycardia" conventionally refers to the group of rhythm disturbances encompassing sinus tachycardia (appropriate and inappropriate), atrial tachycardia, atrial flutter, atrioventricular nodal reciprocating tachycardia (AVNRT) and atrioventricular reciprocating tachycardia (AVRT) including the Wolff Parkinson White syndrome (WPW). Atrial fibrillation is beyond the scope of this article which focuses on the diagnosis and acute management of the patient presenting with one of these common causes of a regular, narrow complex tachycardia.