Re-entry Circuit Location

Re-entry circuits are found:

• Entirely within the AV node – AV-nodal re-entry tachycardias (AVNRT) (Fig 1)
• In the presence of an accessory pathway in junctional tissue- AV re-entry tachycardias (AVRT), E.g., Wolff-Parkinson-White Syndrome (Fig 2)

Fig 1: AV Nodal re-entry tachycardia (AVNRT)	Fig 2: AV re-entry tachycardia (AVRT)

 We will look at each of these in turn.