Evaluation of QTc dispersion, P-wave dispersion, and Tp-e interval in girls diagnosed with central precoccigous puberty

It has been shown that the usage of Leuprolide acetate (LA) as a gonadotropin-releasing hormone analog, may cause alterations in ventricular repolarization in adults. In this study, to evaluate the effects of LA on arrhythmogenesis, electrocardiographic (ECG) parameters obtained at the beginning, 6th and 12th months of the treatment were compared in 28 girls receiving LA for the treatment of central precocious puberty. Also correlations of ECG parameters with simultaneously measured hormone levels were assessed. At the 12th month of treatment, compared to the begining, the minimum QT interval and Tp-e/QTc ratio were significantly prolonged (p=0,010 and p=0,012), while heart rate significantly decreased (p=0,001). A negative correlation was observed between the basal serum LH levels and the maximum QT interval duration (r=-0,435; p=0,021), and between serum TSH levels and the maximum P-wave duration (r=-0,471; p=0,011). At the 6th month of treatment, negative correlations were detected between serum LH levels measured 90 minutes after LA injection and minimum QTc duration (r=-0,408; p=0,031), Tp-e/QT ratio (r=-0,515; p=0,005), and Tp-e/QTc ratio (r=-0,532; p=0,004). At the 12th month of treatment, negative correlations were observed between pre-LA injection serum LH levels and both maximum QTc duration (r=-0,462; p=0,013) and QTc dispersion (r=-0,569; p=0,020), as well as between serum FSH levels and PR interval (r=-0,383; p=0,044). In conclusion, our study suggests that although LA treatment in children cause some changes in ECG parameters reflecting ventricular repolarization and atrial depolarization, these alterations are not at a level that would cause clinical arrhythmia. Therefore, it can be considered that in cardiologic aspect, LA can be used in the pediatric population with ECG monitoring.