Introduction:
Diabetic cardiomyopathy (DCM) is a serious complication that frequently occurs in patients with type 1 diabetes (T1D) necessitating early diagnosis. The aim of the current study was to detect subclinical DCM in Egyptian children and adolescents with T1D and evaluate the effect of antioxidants on myocardial dysfunction.

Material and methods:
The current prospective observational cohort study included 81 T1D patients (9-20 years old) with diabetes duration > 4 years compared to 50 age and sex matched non-diabetic controls. Serum N-terminal prohormone of brain natriuretic peptide (NT-proBNP) was assessed in addition to conventional echocardiography, tissue Doppler imaging (TDI) and speckle tracking echocardiography (STE). Patients with myocardial dysfunction were supplemented with vitamin E (α-tocopherol) as an antioxidant for 1 year, then follow up echocardiography was done.

Results:
NT-proBNP was elevated in 73 (90.1%) patients, 50.6% had left ventricular (LV) diastolic dysfunction, 14.8% had right ventricular (RV) diastolic dysfunction, 84% had LV systolic dysfunction and 91.4% had RV systolic dysfunction with statistically significant difference compared to controls. There was a significant negative correlation between LV global longitudinal strain (GLS) and NT-proBNP (p<0.001, r=-0.796). ROC curve analysis showed that NT-proBNP at a cut-off point ≥ 195 ng/ml detected LV systolic dysfunction function with 89.7% sensitivity and 84.6% specificity. Follow up after one year of α-tocopherol supplementation revealed significant improvement in LV systolic and diastolic functions as well as RV systolic dysfunction.

Conclusions:
NT-proBNP and non-conventional echocardiography were useful in early detection of subclinical cardiomyopathy in patients with T1D. Antioxidant treatment improved subclinical myocardial dysfunction in T1D patients.