Ventricular depolarization and repolarization variability in children with type 1 diabetes mellitus

Background Arrhythmias can be seen as a sign of cardiac autonomic neuropathy in type 1 diabetes mellitus. We aimed to evaluate pulmonary artery pressure, ventricular depolarization and repolarization variability in children with type 1 diabetes mellitus. Methods We investigated 78 children with type 1 diabetes mellitus (mean age 11.6 +/- 3.6 years) and 68 age-gender matched healthy children as control group. All type 1 diabetes mellitus patients were divided into three subgroups according to glycated hemoglobin (HbA1c) levels and the duration of disease. Electrocardiogram and transthoracic echocardiograms were performed on both groups. Results In patients with type 1 diabetes mellitus, there was an elongation in P, Pd, PR, QTc, QTd, QTcd, JT, JTc, JTd, Tp-Te and Tp-Te/QT, Tp-Te/QTc, Tp-Te/JT, Tp-Te/JTc ratios were higher (P < 0.05). In patients with type 1 diabetes mellitus, pulmonary artery pressure was higher than control group (P = 0.001). Prolongation of QTc, thickness of left ventricle end-diastolic diameter and left ventricle posterior wall diameter were higher in the HbA1c >= 9% subgroup. When adjusted for age there was no significant correlation between left ventricle parameters and HbA1c. Conclusions Atrial conduction delay and impairment of ventricular repolarization were significantly high and there was a predisposition for the development of pulmonary artery hypertension in children with type 1 diabetes mellitus. Poor glycemic control was not a risk factor for propensity of left ventricle hypertrophy and left ventricle dysfunction.