A change in QT interval and ST-segment after radiofrequency catheter ablation in pediatric patients with Wolff–Parkinson–White syndrome

Background: Few studies have examined QT, JT interval, and ST-segment changes due to radiofrequency catheter ablation (RFA) in manifest Wolff–Parkinson–White (WPW) syndrome in pediatric patients. Methods: The study involved 27 patients (male-to-female, 13:14; age, 12 (5–16) years) who were diagnosed with WPW syndrome and underwent RFA in our hospital between 2009 and 2022. Electrocardiographic (ECG) changes were compared between the group with ventricular preexcitation due to an accessory pathway (manifest group, n = 16) and those without it (concealed group, n = 11). Results: The QT interval before RFA was significantly longer in the manifest group than in the concealed group (402 [362–482] vs. 344 [323–427]; p = 0.001). The QT interval was significantly shortened in the manifest group before and after RFA (402 [362–482] vs. 360 [298–422] msec; p = 0.01). At 1 month, the QT interval difference between the manifest and concealed groups disappeared (366 [305–437] vs. 335 [301–436] msec; p = 0.001). ST-segment changes were found after RFA in 63% (10/16) of the patients in the manifest group but not in the concealed group. ECG changes presenting the Brugada-pattern were found in two patients. One month later, ECG abnormalities persisted in only one patient. Conclusions: In cases of prolonged QT interval or ST-segment abnormalities lasting > 1 month after RFA, the coexistence of manifest WPW syndrome with long QT syndrome or Brugada syndrome may be considered.