Late cardiac damage of anthracycline therapy for acute lymphoblastic leukemia in childhood

Long-term leukemia survivors (46) underwent cardiac evaluation, including p hysical examination, ECG, exercise testing, and echocardiography. They were 2-17 years old at diagnosis and 5-23 gears old after treatment. Thirty-fou r survivors received anthracyclines (AC) (mean 203 mg/m(2)), 12 of them had also alkylating agents (AA) and 12 had no AC. Exercise tolerance was bello w predicted values in 21 (48%) survivors and 21 survivors had ECG abnormali ties, which were more frequent in those treated with AC. Concomitant AC wit h AA was correlated with prolonged isovolumic relaxation time (IVRT) and in fluenced significantly the volume of left atrium (p =.02). Sixteen (52%) su rvivors had IVRT greater than or equal to 90 ms. There were no significant differences in other parameters of diastolic or systolic function. Despite the lack of clinical symptoms in the survivors treated with lower doses of AC, subtile abnormalities in myocardial function were found, mainly manifes t as abnormal diastolic function. Prolonged IVRT may be a sensitive indicat or for early detection of AC cardiotoxicity.