Monday, 14 November 2016

Junctional Tachycardia

Junctional tachycardia is a form of supraventricular tachycardia characterized by involvement of the AV node. It can be contrasted to atrial tachycardia. It is a tachycardia associated with the generation of impulses in a focus in the region of the atrioventricular node due to an AV disassociation. In general, the AV junction's intrinsic rate is 40-60 bpm so junctional tachycardia implies a rate >60 bpm.

On an ECG, Junctional Tachycardia exhibits the following classic criteria:
  • P Waves: The P Wave may be inverted in leads II, III and aVF or not visible
  • Narrow QRS complexes (which is consistent with non-ventricular rhythms)
It can coexist with other superventricular tachycardias due to the disassociation between the SA node and the AV node. Junctional Tachycardia can appear similar to atrioventricular nodal reentrant tachycardia (AVNRT). One form is junctional ectopic tachycardia.