QTc interval prolongation in children with Ulrich-Turner syndrome.
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.
Dalla Pozza
Robert
R
Department of Pediatric Cardiology, Ludwig-Maximilians-University, Marchioninistr. 15, 81377, Munich, Germany. Robert.DallaPozza@med.uni-muenchen.de
Bechtold
Susanne
S
Kääb
Stefan
S
Buckl
Matthias
M
Urschel
Simon
S
Netz
Heinrich
H
Schwarz
Hans-Peter
HP
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*