Late onset of Wolff-Parkinson-White syndrome in a 72-year-old man.

We encountered a case of wide QRS tachycardia with chronic atrial fibrillation in Wolff-Parkinson-White syndrome. Unique features were late onset of syncope attacks associated with this tachycardia at an advanced age of 72 years old without previous documentation of Wolff-Parkinson-White syndrome on electrocardiogram. He had a high likelihood of sudden cardiac death. Catheter ablation using CARTO system easily led to a successful ablation of the accessory pathway. The mechanism of late onset of the wide QRS tachycardia was attributed to possible changes of electrophysiologic properties including the atrio-ventricular node and/or the accessory pathway, and the unique location of the accessory pathway.