title: T(peak)T(end) interval in long QT syndrome.
abstract: BACKGROUND
  The T(peak)T(end) (T(p)T(e)) interval is believed to reflect the transmural dispersion of repolarization. Accordingly, it should be a risk factor in long QT syndrome (LQTS). The aim of the study was to determine the effect of genotype on T(p)T(e) interval and test whether it was related to the occurrence of syncope.
  
  
  METHODS
  Electrocardiograms were taken in 95 patients with LQTS drawn from the Danish long QT registry (44 patients with KvLQT1, 43 with HERG, and 8 with SCN5A mutations) and manually evaluated for the QT, QT(peak), and RR interval.
  
  
  CONCLUSIONS
  (1) T(p)T(e) cannot be used to distinguish symptomatic from asymptomatic patients with LQTS; (2) HERG patients have longer T(p)T(e) than KvLQT1 patients; and (3) there is no need to heart rate-correct T(p)T(e) intervals in patients with LQTS.
authors.affiliation: Danish National Research Foundation Center of Arrhythmias (DARC), Copenhagen, Denmark.
authors.forename: Jorgen K
authors.initials: JK
authors.lastname: Kanters
authors.forename: Christian
authors.initials: C
authors.lastname: Haarmark
authors.forename: Esben
authors.initials: E
authors.lastname: Vedel-Larsen
authors.forename: Mads P
authors.initials: MP
authors.lastname: Andersen
authors.forename: Claus
authors.initials: C
authors.lastname: Graff
authors.forename: Johannes J
authors.initials: JJ
authors.lastname: Struijk
authors.forename: Poul Erik Bloch
authors.initials: PE
authors.lastname: Thomsen
authors.forename: Michael
authors.initials: M
authors.lastname: Christiansen
authors.forename: Henrik K
authors.initials: HK
authors.lastname: Jensen
authors.forename: Egon
authors.initials: E
authors.lastname: Toft
mesh_terms: D000328:Adult; D015897:Comorbidity; D003718:Denmark / Q000453:epidemiology; D003936:Diagnosis, Computer-Assisted / Q000379:methods*; D004562:Electrocardiography / Q000379:methods* / Q000706:statistics & numerical data*; D005260:Female; D006801:Humans; D015994:Incidence; D008133:Long QT Syndrome / Q000175:diagnosis* / Q000453:epidemiology*; D008297:Male; D015203:Reproducibility of Results; D018570:Risk Assessment / Q000379:methods*; D012307:Risk Factors; D012680:Sensitivity and Specificity; D013575:Syncope / Q000175:diagnosis* / Q000453:epidemiology*