QT interval and dispersion in very young children treated with antipsychotic drugs: a retrospective chart review

OBJECTIVES AND BACKGROUND: QT dispersion (QTd) is a measure of interlead variations of the surface 12-lead electrocardiogram (ECG). Increased QTd, found in various cardiac diseases, reflects cardiac instability and risk for lethal cardiac arrhythmias. Research suggests a link between psychotropic treatment, ECG abnormalities (QT prolongation), and increased sudden cardiac mortality rates. Reports of sudden death in children treated with psychotropic drugs have raised concerns about cardiovascular monitoring and risk stratification. QTd analysis has not been investigated in very young children treated with antipsychotic drugs. In the present retrospective chart review study, we calculated QT interval, QTd, and their rate-corrected values in very young children treated with antipsychotics. METHODS: The charts of 12 children (ages 5.8 +/- 0.98 yr; 4 girls, 8 boys) were examined before initiation of antipsychotic treatment [risperidone (n = 7), clotinapine (n = 1), and propericiazine (n = 4)] and during the maintenance period after achieving a positive clinical response. Three children were concomitantly maintained on methylphenidate. QT interval, QTd, and their rate-corrected values were calculated. RESULTS: QT interval, QTd, and their rate-corrected values were all within normal values both before and after successful drug treatment. CONCLUSIONS: This preliminary, naturalistic, small-scale study suggests that antipsychotic treatment, with or without methylphenidate, in very young children is not commonly associated with significant alterations of QT interval and dispersion, suggesting the relative safety of these agents in this unique age group.