title: Interval representative of transmural dispersion of repolarization in children and young adolescents with congenital long QT syndrome.
abstract: BACKGROUND
  It has been shown experimentally that the interval from the nadir of the initial negative T wave to the end of the T wave is representative of transmural dispersion of repolarization (TDR) when complex T waves are present. In the clinical setting, however, the interval representative of TDR in patients with long QT syndrome (LQTS) is a controversial subject.
  
  
  RESULTS
  Five symptomatic patients (3 boys, 2 girls; 3 LQT1, 2 LQT2) were evaluated by a face immersion test before and after treatment to compare the configuration of the T wave. When the notch disappeared after treatment, the single peak of the T wave after treatment coincided with the nadir of the notch before treatment. When the notch remained the same after treatment as before treatment and when the QTc decreased, the corrected interval from the nadir of the notch to the end of the T wave was for the most part shortened.
  
  
  CONCLUSIONS
  The present study showed that the interval representative of the TDR in the clinical surface electrocardiogram can be obtained from the nadir of the notch to the end of the T wave in children and adolescents with LQTS, as was shown in the experimental study.
authors.affiliation: Department of Pediatrics, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima, Japan.
authors.forename: Yasue
authors.initials: Y
authors.lastname: Haraguchi
authors.forename: Masao
authors.initials: M
authors.lastname: Yoshinaga
authors.forename: Jav
authors.initials: J
authors.lastname: Sarantuya
authors.forename: Atsushi
authors.initials: A
authors.lastname: Shimago
authors.forename: Junichiro
authors.initials: J
authors.lastname: Nishi
authors.forename: Yukiharu
authors.initials: Y
authors.lastname: Kono
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Nomura
authors.forename: Rieko
authors.initials: R
authors.lastname: Kubo
authors.forename: Taisuke
authors.initials: T
authors.lastname: Eguchi
authors.forename: Satoru
authors.initials: S
authors.lastname: Tanaka
authors.forename: Sadamitsu
authors.initials: S
authors.lastname: Yanagi
authors.forename: Toshiro
authors.initials: T
authors.lastname: Fukushige
authors.forename: Ikuro
authors.initials: I
authors.lastname: Maruyama
authors.forename: Yoshifumi
authors.initials: Y
authors.lastname: Kawano
mesh_terms: D000293:Adolescent; D000319:Adrenergic beta-Antagonists / Q000627:therapeutic use; D000328:Adult; D002648:Child; D004562:Electrocardiography; D005260:Female; D006801:Humans; D007101:Immersion; D008133:Long QT Syndrome / Q000235:genetics / Q000628:therapy*; D008297:Male; D012016:Reference Values; D013575:Syncope / Q000209:etiology
chemical_list: D000319:Adrenergic beta-Antagonists