AV reciprocating tachycardia
AV reciprocating tachycardia (AVRT) occurs in patients with an accessory pathway which circumvents the AV node, which causes pre-excitation of the ventricles. This occurs most commonly in patients with Wolff-Parkinson-White syndrome. It is triggered by a premature atrial or ventricular beat. Treatment involves ablation of the accessory pathway.
In patients with WPW (but not currently in AVRT), pre-excitation is visible as delta-waves, and the PQ-interval is decreased.