Prolonged QT interval in Rett syndrome

Rett syndrome is a severe neurodevelopmental disorder of unknown aetiology. A prolonged QT interval has been described previously in patients with Ret t syndrome. To investigate QT prolongation and the presence of cardiac tach yarrhythmias in Rett syndrome electrocardiography and 24 hour Holter monito ring were performed prospectively in a cohort of 34 girls with Rett syndrom e. The corrected QT value was prolonged in nine patients. Compared with a g roup of healthy controls of a similar age range, the patients with Rett syn drome had significantly longer corrected QT values. Clinical severity was n ot a predictor for prolonged QT intervals in the Rett syndrome cohort. The prolonged QT syndrome is a serious and potentially lethal cardiac disorder and should be considered in all girls with Rett syndrome.