ECHOCARDIOGRAPHIC EARLY DIASTOLIC ALTERATIONS IN PEDIATRIC TYPE 1 DIABETES MELLITUS

Abstract

Objective: To evaluate left ventricular systolic and diastolic function using conventional and tissue Doppler echocardiography in pediatric patients with type 1 diabetes mellitus (T1DM) and to explore associations with serum tumor necrosis factor-alpha (TNF-α). Methods: This prospective cross-sectional comparative study included 31 children and adolescents with T1DM (median disease duration: 2.4 years) and 31 age- and sex-matched healthy controls. Tissue Doppler assessment included isovolumic contraction and relaxation times, ejection time (ET), myocardial performance index (MPI), and E/Em. Time intervals were additionally examined using analysis of covariance with resting heart rate as a covariate. Results: The groups were comparable in age and anthropometric characteristics. Resting heart rate was higher in the T1DM group (p=0.023), whereas conventional systolic parameters were similar. In unadjusted analyses, septal, lateral, and tricuspid ET were shorter and lateral MPI was higher in the T1DM group; however, none remained statistically significant after heart rate adjustment (all p>0.05). Lateral E/Em was modestly higher in the T1DM group (p=0.013), although most values were within published pediatric reference limits. TNF-α concentrations did not differ between groups (p=0.964). Exploratory analyses identified modest correlations of selected diastolic indices with HbA1c and diabetes duration. Conclusion: In children and adolescents with relatively short-duration T1DM, conventional systolic function was preserved, and heart rate-adjusted tissue Doppler time intervals did not indicate overt myocardial dysfunction. The isolated lateral E/Em difference and exploratory correlations should be interpreted cautiously because their clinical significance remains uncertain.