title: QTc interval prolongation in children with Ulrich-Turner syndrome.
abstract: BACKGROUND
  The Ullrich-Turner-Syndrome (UTS) is the most commonly occurring sex chromosome abnormality in females. Cardiac malformations are well known, but no data exist on specific electrocardiogram (ECG) patterns in children and adolescents. A prolongation of the QT interval on the ECG has been correlated to an increased risk for sudden cardiac death, and medical treatment is warranted in patients with long QT syndrome (LQTS). Moreover, several drugs of common use are contraindicated in LQTS because of their effects on myocardial repolarization.
  
  
  METHODS
  The ECG tracings of 86 UTS patients [mean age (+/-SD): 11.0+/-3.6 years; mean height-SD: -2.6+/-1.0] were analyzed and compared to age-matched control groups of 75 boys (mean age: 11.3+/-3.5 years; mean height-SD: -1.9+/-1.0) and 62 girls (mean age: 10.1+/-3.2 years; mean height-SD: -2.5+/-0.9) with short stature.
  
  
  RESULTS
  Eighteen UTS patients (20.9%) had an abnormally prolonged QTc >0.45 s in contrast to only one control subject (0.9%). The QTc interval of UTS patients was significantly prolonged compared to that of the controls (p<0.01) and normal values.
  
  
  CONCLUSIONS
  There is an increased prevalence of a long QT interval among UTS patients. This should be taken into account for the cardiovascular screening of such patients. Patients with UTS have an intrinsically prolonged QT interval and as such may be at higher risk for arrhythmias in the context of a QT-prolonging medication.
authors.affiliation: Department of Pediatric Cardiology, Ludwig-Maximilians-University, Marchioninistr. 15, 81377, Munich, Germany. Robert.DallaPozza@med.uni-muenchen.de
authors.forename: Robert
authors.initials: R
authors.lastname: Dalla Pozza
authors.forename: Susanne
authors.initials: S
authors.lastname: Bechtold
authors.forename: Stefan
authors.initials: S
authors.lastname: Kääb
authors.forename: Matthias
authors.initials: M
authors.lastname: Buckl
authors.forename: Simon
authors.initials: S
authors.lastname: Urschel
authors.forename: Heinrich
authors.initials: H
authors.lastname: Netz
authors.forename: Hans-Peter
authors.initials: HP
authors.lastname: Schwarz
mesh_terms: D015992:Body Mass Index; D016022:Case-Control Studies; D002648:Child; D004562:Electrocardiography; D005260:Female; D006801:Humans; D008133:Long QT Syndrome / Q000150:complications* / Q000175:diagnosis; D008297:Male; D012189:Retrospective Studies; D014424:Turner Syndrome / Q000150:complications*