Clinical AV nodal reentrant tachycardia in a patient with left sided accessory pathway and immediate occurrence of antidromic AV reentrant tachycardia after slow pathway ablation.

The only inducible arrhythmia in a patient with exclusive antegrade conducting left anterolateral accessory pathway, consists of slow/fast atrioventricular nodal reentrant tachycardia. After radiofrequency catheter ablation of the slow pathway, true antidromic AV reentrant tachycardia was easily induced by atrial pacing. Following ablation of the accessory pathway no arrhythmia could be induced.