Tachycardia Supraventricular tachycardia UMLS:C0039240 Supraventricular tachyarrhythmia A narrow complex (QRS width less than 120 milliseconds) reflects rapid activation of the ventricles via the normal conduction pathway, i.e. His-Purkinje system, which in turn suggests that the tachycardia originated above the AV node and is thus supraventricular. HP:0004755 Supraventricular tachycardia (SVT) is an abnormally increased heart rate (over 100 beats per minute at rest) with origin above the level of the ventricles. SNOMEDCT_US:6456007 SVT UMLS:C1698480 Supraventricular arrhythmia