The signal-averaged electrocardiogram in diabetic children

A signal averaged ECG is a useful tool for detecting low-amplitude, high frequency electrical potentials in the terminal portion of QRS. There is a close association between abnormal signal averaged ECG and coronary heart disease. In this study we evaluated late potentials and total QRS duration determined by this technique in diabetic children with and without good glycemic control. The signal averaged ECG of 20 children with diabetes mellitus and nine healthy age-matched controls were compared. The total QRS duration was longer in diabetic children than in controls (104.6, and 97.9 ms vs. 82.7 ms, P < 0.0005). Late potentials were not observed in the patient and control groups. The RMS voltage of the QRS complex in the last 40 ms was significantly lower in the diabetic group compared to the control group. There was no significant difference in the signal averaged ECG indexes between the two diabetic groups determined by the glycemic control state. These findings suggested that the children with diabetes mellitus frequently have intraventricular conduction disturbance regardless of glycemic control condition.