Persistent T-wave changes after radiofrequency catheter ablation of an accessary connection (Wolff-Parkinson-White syndrome) are caused by "cardiac memory"

Background The purpose of this study was to determine the incidence and ori gin of T-wave changes after ablation of an accessory atrioventricular conne ction (AC), which could either be a sign of damage to the coronary circulat ion or a result of persistent abnormal repolarization secondary to previous ly abnormal ventricular activation ("cardiac memory"). Methods and Results Ninety of 107 consecutive patients (33 women and 57 men , mean age 36 +/- 5 years) undergoing successful catheter ablation of an AC were studied. Patients with bundle branch block or more than 1 AC were exc luded. Sixty-four patients had manifest preexcitation (group 1) and 26 had a concealed AC (group 2). immediately after loss of preexcitation, 38 (59%) patients with a manifest AC showed T-wave abnormalities. In contrast, none of the patients with a concealed AC had T-wave abnormalities after ablatio n (P < .05). The T-wave changes (1) did not correlate with the number or du ration of energy applications or with markers of tissue injury; (2) correla ted with the location of the AC and the degree of preexcitation, respective ly; and (3) completely resolved over a period of weeks to months. None of t he patients had recurrence of preexcitation or tachycardia during a mean fo llow-up of 16 +/- 7 months. Conclusions T-wave changes after ablation are most likely caused by "cardia c memory" and are not a sign of myocardial or coronary injury.