Prevalence of prolonged QTcinterval in electrocardiograms of 1 -12 year-old seizure patients

Background: Children with long QT intervals are prone to life-threatening ventricular arrhythmias which may lead to seizure and syncope and may be misdiagnosed as seizure. Objective: This study aimed to assess the frequency of long QT intervals in children with and without convulsion. Method: This study is case-control. ECG tracings were requested for all children aged between one to twelve years who were hospitalized due to convulsion with no underlying etiology and simultaneously for children of the same age and gender who were admitted due to other than seizure as case group. Consequently, QT intervals were measured and compared in the two  groups. Results: If long QT interval was defined to be longer than 0.47 second, no significant difference was noted between two groups. On the other hand, if this interval was defined to be equal to or longer than 0.46 second, long QT intervals are more frequent in convulsive children. Conclusions: In this study, long QT interval, defined as QT interval 0.46 second, is found more frequently in children with seizure than non-convulsing ones. It is recommended that children with history of seizure without any identifiable causes and that is unresponsive to  anticonvulsive drugs should be investigated with ECG.Key words: Child, Diagnostic Errors, Long QT Syndrome, Seizur