Left ventricular diastolic Doppler characteristics in beta-thalassemia major.

BACKGROUND: Diastolic left ventricular function expressed by diastolic Doppler characteristics of the left ventricle has never been properly investigated. METHODS AND
RESULTS: Left ventricular inflow and pulmonary vein flow patterns were assessed by Doppler echocardiography in 88 beta-thalassemia major patients with normal left ventricular systolic function; 34 were young (age, 15.1 +/- 3.2 years) and 54 were adults (age, 25.1 +/- 3.6 years). The findings were compared with those obtained from 22 young (age, 13.8 +/- 2.4 years) and 24 adult (age, 25.3 +/- 4.1 years) normal individuals. In both groups of patients, peak flow velocities in early (E) and late (A) diastole were higher than in the control subjects (young E: P < .01; adult E: P < .001; young A: P < .05; adult A: P < .05), whereas no difference was found in the E/A ratio, deceleration time, or isovolumic relaxation time. Pulmonary vein systolic (S) and diastolic (D) velocities were also higher in beta-thalassemia major patients compared with the control subjects (young S: P < .05; adult S: P < .05; young D: P < .05; adult D: P < .05). Restrictive left ventricular abnormalities were only found in 7 patients who were among the oldest beta-thalassemia major population of the adult group (P < .01) with highly elevated mean serum ferritin. In comparison to the remaining adult patients, interventricular septum and left ventricular posterior wall thickness were increased (P < .01 and P < .01, respectively). The left atrium and right ventricle were dilated (P < .05 and P < .01, respectively).
CONCLUSIONS: Doppler diastolic indexes in beta-thalassemia major patients with normal left ventricular systolic function are similar to those seen in conditions with an increased preload, probably because of chronic anemia. Only severe iron loading and deposition in the myocardium leads to the restrictive abnormalities of left ventricular filling.