Objective: Corrected QT (QTc) interval prolongation has been described after subarachnoid hemorrhage and head injury in adults. Abnormal QTc prolongation is associated with a higher risk of ventricular arrhythmias. The aim of this study was to analyze QTc interval and QTc dispersion in children with severe head trauma.
Methods: Forty-three patients with severe head trauma and 49 children with no or only mild head injury as controls were enrolled in the study. QT interval from standard 12-lead electrocardiogram immediately after admission was calculated. QT interval was corrected by heart rate according to Bazett formula, and then QTc dispersion was calculated. At the same time, levels of serum electrolytes were measured.
Results: Although no significant difference in terms of age, sex, and R-R interval was found, QTc interval and QTc dispersion values were significantly increased in the patients with severe head trauma compared with those with no or only mild head injury (QTc, 447 ± 31 vs. 409 ± 27 milliseconds; QTc dispersion, 77 ± 22 vs. 52 ± 16 milliseconds, respectively). When the patients with severe head trauma were categorized as those with or without intracranial hemorrhage, both QTc interval and QTc dispersion were significantly greater in those with intracranial hemorrhage. These electrocardiographic parameters were inversely associated with Glasgow Coma Scale score, serum calcium levels, and, at a lesser degree, potassium levels.
Conclusions: Children with severe head trauma, especially those with intracranial hemorrhage have longer QTc interval and greater QTc dispersion.