Tissue Doppler imaging and NT-proBNP levels show the early impairment of ventricular function in patients with ß-thalassaemia major

Abstract

Beta-thalassaemia major is a chronic haemolytic anaemia, and congestive heart failure (CHF) is the most common cause of death in this disease. N terminal pro B type natriuretic peptide (NT-proBNP) increases with the severity of CHF and predicts the prognosis. The aim of this study was to investigate the relation between left ventricular systolic and diastolic function determined by standard pulsed wave Doppler (PWD), tissue Doppler imaging (TDI) and NT-proBNP in patients with beta-thalassaemia major. Thirty-four patients with beta-thalassaemia major and 34 healthy individuals were included in the study. Blood samples were taken for NT-proBNP. All patients and controls underwent echocardiographic examination. All cardiac chambers were significantly increased in the patient group. Left and right ventricular (LV, RV) ejection fractions and all diastolic parameters were normal in the patients and controls. Tissue Doppler imaging (TDI) showed a significant decrease in LV and RV Sm velocities in patients compared to the controls. NT-proBNP levels were also significantly higher in the patient group. There was a negative correlation between serum NT-proBNP levels and LV Sm and RV Sm velocities in patients (r = -0.426, P = 0.006 and r = -0.409, P = 0.009, respectively). Linear regression analysis showed that LV Sm and RV Sm were independent predictors for NT-proBNP. Our findings suggest that although iron overload in patients with beta-thalassaemia major impairs the systolic and diastolic functions of both ventricles, it impairs the systolic function earlier than diastolic function. Tissue Doppler imaging is an easy and reliable method in the early determination of ventricular dysfunction in these patients.

Detection of Early Cardiac Dysfunction in Patients with Beta Thalassemia by Tissue Doppler Echocardiography

“…It is of interest that EF was significantly reduced in the group of patients with Sm < 7.9 cm/s, though its value was in the normal range (56%). These findings are consistent with a previous study that demonstrated impairment of peak systolic velocity (Sm), despite a normal EF 7 . Furthermore our results corroborate findings of other recent researches which have demonstrated a pivotal role of TDI in detecting early myocardial damage in such patients.…”

“…B‐type natriuretic peptide (BNP) and his inactive metabolite NT‐proBNP have been shown to be sensitive plasmatic markers of heart failure, usually correlated to prognosis, although its predictive role in asymptomatic thalassemic patients is not yet well established. 7–9 …”

Relation between NT‐proBNP Levels, Iron Overload, and Early Stage of Myocardial Dysfunction in β‐Thalassemia Major Patients

“…Authors only correlated BNP levels with mitral E and A velocities and a positive correlation was found only among patients with normal systolic function. Akpinar et al 27 demonstrated no association between mitral inflow and TDI parameters and NT-proBNP levels in a β-TM patient group of a similar mean age. 32 We identified no correlation between TDI parameters and NT-proBNP levels but there was a mild positive correlation between LAVI and NT-proBNP levels only in patients with E/E ratio ≥ 9.…”

“…15,16 In these studies, natriuretic peptide levels in β-TM patients correlated with the presence of diastolic LV dysfunction. 26,27 Few studies only included mitral inflow E and A velocities and their ratio as a surrogate marker of diastolic functions 5,28 whereas some studies included TDI and strain imaging methods for the estimation of diastolic filling pressures. However, in our study, we did not find a significant correlation between plasma NT-proBNP levels and diastolic dysfunction parameters.…”

“…In another study, Kremastinos et al 15 suggested that NT-proBNP increased in β-TM patients and this increase correlated with age and LV diastolic dysfunction. 27,29 But even some of these studies have not clearly documented the correlation of NT-proBNP with E , E/E ratio, and LAVI. The reason for the lack of this correlation may be that the mean age of our patient population was lower and the range of age was narrow.…”