Evaluation of QT dispersion in beta thalassaemia major patients.

Cardiac complications are considered to be the primary cause of death in patients with beta thalassaemia major. QT dispersion is a marker variability of ventricular repolarization and is elevated in various high risk groups of patients. This study was carried out in patients with beta thalassaemia major to evaluate QT dispersion and to investigate the relationship between QT dispersion and body iron load. Sixty-two beta thalassaemia major patients were enrolled into the study. The average serum ferritin levels and liver iron concentration was assessed. For each patient, QT-QTc intervals and QT-QTc dispersions were calculated and V1S and V5R were measured. All the subjects underwent two-dimensional M mode echocardiogram and Doppler study. LVMI was found higher in thalassaemia major patients compared to control group. beta thalassaemia major patients showed significantly higher mean QT, QTc, QTd, and QTcd values compared to the control group. The mean V5R and V1S amplitudes were also higher in beta thalassaemia major patients. There was a positive correlation between LVMI and QTc, QTd and QTcd. However, there was no significant correlation between QT dispersion and serum ferritin and liver iron concentration. Prospective longitudinal studies are needed to assess the prognostic significance of these findings.