title: Prolonged rate-corrected QT interval and other electrocardiogram abnormalities in girls with Turner syndrome.
abstract: BACKGROUND
  We recently reported that electrocardiographic abnormalities are common in adults with monosomy X (Turner syndrome), but this issue has not been investigated in girls with Turner syndrome.
  
  
  METHODS
  We analyzed electrocardiograms in 78 girls with Turner syndrome and 50 age-matched control girls. The girls with Turner syndrome had additional cardiac and metabolic evaluations.
  
  
  RESULTS
  Girls with Turner syndrome were more likely to demonstrate > or = 1 electrocardiographic findings including right axis deviation, right ventricular hypertrophy, accelerated atrioventricular conduction, T-wave abnormalities, and a prolonged rate-corrected QT interval. The right-sided findings were associated with partial anomalous pulmonary venous connection, but the etiology of the other findings remains unknown. The rate-corrected QT interval was significantly longer in girls with Turner syndrome (431 +/- 22 vs 407 +/- 21 milliseconds). Twenty-eight girls with Turner syndrome but only 2 controls had a rate-corrected QT interval above the reference range. We found no correlation between body habitus, cardiac dimensions, or metabolic parameters and the rate-corrected QT interval duration in girls with Turner syndrome.
  
  
  CONCLUSIONS
  Cardiac conduction and repolarization abnormalities seem to affect both young girls and adults with Turner syndrome equally, suggesting that electrophysiologic defects are intrinsic to the syndrome and indicating that electrocardiogram analysis should be included in evaluating and monitoring even the youngest patients with Turner syndrome. Attention to the rate-corrected QT interval is important, because some common medications may further prolong this interval and increase the risk of arrhythmias.
authors.affiliation: Developmental Endocrinology Branch, National Institute of Child Health and Human Development, NIH, Building 10 CRC, Room 1-3330, Bethesda, MD 20892-1103, USA. bondyc@mail.nih.gov
authors.forename: Carolyn A
authors.initials: CA
authors.lastname: Bondy
authors.forename: Irene
authors.initials: I
authors.lastname: Ceniceros
authors.forename: Phillip L
authors.initials: PL
authors.lastname: Van
authors.forename: Vladimir K
authors.initials: VK
authors.lastname: Bakalov
authors.forename: Douglas R
authors.initials: DR
authors.lastname: Rosing
mesh_terms: D000293:Adolescent; D002648:Child; D004452:Echocardiography; D004562:Electrocardiography; D005260:Female; D006329:Heart Conduction System / Q000503:physiopathology; D006352:Heart Ventricles / Q000000981:diagnostic imaging / Q000473:pathology; D006801:Humans; D007621:Karyotyping; D008133:Long QT Syndrome / Q000209:etiology* / Q000503:physiopathology; D014424:Turner Syndrome / Q000150:complications* / Q000235:genetics / Q000503:physiopathology