title: Changes in repolarization properties with long-term cardiac memory modify dispersion of repolarization in patients with Wolff-Parkinson-White syndrome.
abstract: BACKGROUND
  Transient T wave changes after cessation of preexcitation have been attributed to cardiac memory. However, there have been no reports on the effects of long-term cardiac memory on repolarization dispersion before and after catheter ablation in patients with Wolff-Parkinson-White (WPW) syndrome.
  
  
  RESULTS
  We investigated 47 patients with an accessory pathway (AP; 24 manifest left-sided, 14 manifest right-sided, and 9 concealed left-sided). Repolarization dispersion was analyzed by two methods, recovery time (RT) dispersion and newly proposed T wave width (WT), from 87-lead body surface maps before, 1 day after, and 7 days after catheter ablation. RT dispersion and WT were significantly correlated before, 1 day after, and 7 days after catheter ablation (r = 0.78). In patients with preexcitation, RT dispersion and WT increased significantly (P < 0.05) 1 day after catheter ablation (178 +/- 32 msec and 172 +/- 30 msec) compared with those before (154 +/- 24 msec and 156 +/- 18 msec) and 7 days after catheter ablation (147 +/- 19 msec and 156 +/- 16 msec), respectively. However, there were no significant changes in RT dispersion and WT before and after catheter ablation in concealed WPW syndrome.
  
  
  CONCLUSIONS
  The findings suggest that the abrupt changes in activation sequence increase repolarization dispersion in the presence of previous cardiac memory, and that the dispersion decreases days or weeks after alteration of activation sequence by catheter ablation, with development of new cardiac memory in patients with manifest WPW syndrome.
authors.affiliation: First Department of Internal Medicine, University of Nagoya School of Medicine, Japan.
authors.forename: Yasunobu
authors.initials: Y
authors.lastname: Takada
authors.forename: Yasuya
authors.initials: Y
authors.lastname: Inden
authors.forename: Makoto
authors.initials: M
authors.lastname: Akahoshi
authors.forename: Yoshihisa
authors.initials: Y
authors.lastname: Shibata
authors.forename: Atsuya
authors.initials: A
authors.lastname: Shimizu
authors.forename: Yukihiko
authors.initials: Y
authors.lastname: Yoshida
authors.forename: Takumi
authors.initials: T
authors.lastname: Yamada
authors.forename: Naoya
authors.initials: N
authors.lastname: Tsuboi
authors.forename: Haruo
authors.initials: H
authors.lastname: Hirayama
authors.forename: Teruo
authors.initials: T
authors.lastname: Ito
authors.forename: Takahisa
authors.initials: T
authors.lastname: Kondo
authors.forename: Hidehiko
authors.initials: H
authors.lastname: Saito
authors.forename: Makoto
authors.initials: M
authors.lastname: Hirai
mesh_terms: D000222:Adaptation, Physiological; D000328:Adult; D000368:Aged; D018780:Body Surface Potential Mapping / Q000379:methods*; D017115:Catheter Ablation; D004594:Electrophysiology; D005260:Female; D006321:Heart / Q000503:physiopathology*; D006329:Heart Conduction System / Q000503:physiopathology*; D006801:Humans; D008297:Male; D008564:Membrane Potentials; D008875:Middle Aged; D009200:Myocardial Contraction; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014927:Wolff-Parkinson-White Syndrome / Q000175:diagnosis* / Q000503:physiopathology* / Q000601:surgery