Ectopic atrial tachycardia after transvenous catheter ablation of a posteroseptal accessory pathway.

Closed chest electrode catheter ablation of a posteroseptal accessory pathway was performed on an 18 year old patient with recurrent supraventricular tachycardia. After the procedure, ectopic atrial tachycardia was observed for the first time. Detailed endocardial atrial mapping revealed that this ectopic atrial tachycardia originated from the first site of catheter ablation. As retrograde conduction resumed, a second ablation procedure was performed, resulting in successful ablation of both the ectopic atrial tachycardia and the accessory pathway conduction.