Global and Segmental Left Ventricular Function in β-Thalassemia

The systolic and diastolic left ventricular (LV) function was studied by M-mode echocardiography in 60 patients with beta-thalassemia (mean age +/- SD, 17.1 +/- 7.5 years) and 30 healthy controls (15.4 +/- 3.8 years). In thalassemic patients, echocardiograms were obtained 48 h posttransfusion, with a mean hemoglobin level of 12.4 +/- 0.9 g/dl. To examination time, thalassemic patients had received 30-774 blood units (318 +/- 176). Congestive heart failure (CHF) was present in 14 thalassemic patients (19.6 +/- 3.4 years), while 46 (16.3 +/- 8.2 years) had no clinical signs of CHF. Global LV function study showed enlarged LV dimensions in thalassemic patients with CHF (p less than 0.001) and similar cavity size in controls and patients without CHF (p = NS). The same was true for velocity measurements, while diastolic LV indices had similar values in all groups (p = NS). Segmental LV function study showed no significant differences in systolic and diastolic LV posterior wall behavior between thalassemic patients and controls, and even more, between thalassemic patients with and without CHF, while it was independent of iron load. These findings indicate that global and segmental LV function in thalassemic patients remain within normal limits until the final stages of the disease. CHF onset marks the deterioration of LV systolic performance, while global and segmental diastolic indices do not change significantly. The above findings question the role of iron overload in the development of CHF in beta-thalassemia.