RESUMO
OBJECTIVE/BACKGROUND: The purpose of this study was to evaluate serum cardiac troponin I and serum N-terminal (NT) pro-brain natriuretic peptide (pro-BNP) levels and the utility of tissue Doppler imaging in assessing cardiovascular changes following left ventricular (LV) dysfunction in children with beta-thalassemia major (ß-TM). In children with ß-TM who depend on regular blood transfusion, cardiac iron toxicity is a common serious complication. The most common cause of death among these patients is congestive heart failure. METHODS: This is a cross-sectional study which included 50 patients with ß-TM and 50 healthy controls. Tissue Doppler imaging was performed and levels of serum ferritin, cardiac troponin I, and NT pro-BNP were estimated for all included patients. RESULTS: Serum NT pro-BNP and cardiac troponin (cTnI) showed a significant increase in patients with ß-TM (p < .001). In patients with ß-TM, LV dimensions (LV end systolic diameter) and (LV end diastolic diameter) were large (p < .01); LV mass (p < .01), E wave, and E/A ratio (p < .01) were high (p < .05); and deceleration time was short (p < .05). Besides, transmitral ratio (E/Em) (p < .05) and tricuspid valve velocity were higher (p < .05), and early diastolic velocity (Em) (p < .05) and systolic wave velocity (Sm) were lower in patients with ß-TM (p < .05). A significant positive correlation was detected between the pro-BNP and E wave (r = 0.558, p < .001), E/A ratio (r = 0.403, p < .001), E/Em ratio (r = 0.576, p < .001), and ferritin (r = 0.545, p < .001). CONCLUSION: Pulsed wave tissue Doppler imaging and NT pro-BNP had a significant role in the estimation of ventricular dysfunction in children with ß-TM.
