LEFT-VENTRICULAR FUNCTION IN THALASSEMIA MAJOR - PROTECTIVE EFFECT OFDEFEROXAMINE

OBJECTIVE: To test the hypothesis that chelation therapy with deferoxa mine would prevent alterations in left ventricular systolic and diasto lic function due to transfusional iron overload in patients with thala ssemia major. DESIGN: A consecutive series of patients receiving chron ic transfusional and chelation therapy were studied by two-dimensional and Doppler echocardiography.SETTING: Primary clinic. PATIENTS: Eight thalassemic patients (four men and four women), mean age 22 years (ra nge 14 to 28) and seven age and sex matched control subjects. INTERVEN TIONS: All patients had received transfusional therapy since birth, wi th mean annual load of red blood cells of 200 mL/kg. Iron chelation th erapy with deferoxamine, using a subcutaneous infusion pump, was admin istered from age two years in the younger patients and from age 16 yea rs in the two older cases. Doses were 25 mg/kg/day in children and 1.5 to 4 g per 12 h in adults to maintain ferritin blood levels at 1000 t o 1500 ng/L. MAIN RESULTS: No significant differences were found in th e following Doppler diastolic indexes: isovolumic relaxation time, ear ly flow velocity (E wave), late flow velocity (A wave), E:A ratio, rat e of deceleration of flow velocity in early diastole (EF slope), flow velocity deceleration time and end-diastolic volume. Ejection fraction was similar in the two groups (59+/-7 versus 64+/-5%), but contractil ity, expressed as end-systolic pressure/end-systolic volume index, app eared slightly depressed (4.6+/-1 versus 6.7+/-0.8) in the thalassemic group. CONCLUSIONS: Deferoxamine prevents alteration of left ventricu lar diastolic function in chronic transfusional therapy for thalassemi a major. Depression of contractility, in spite of a normal ejection fr action, may be an early sign of worsening systolic performance, unavoi dable even with chelation therapy.