The effect of anthracyclines in minimal doses on cardiac function of children under chemotherapy

Cardiotoxicity of anthracyclines (ANTs) in medium and high doses (more than 350 mg/m2) has been already known but it is still unclear whether or not minimal doses (lower than 350 mg/m2) can also affect cardiac function. The goal of this study was to assess the cardiotoxicity of ANTs in children under minimal doses and evaluation the association of this toxicity with probable risk factors such as age at beginning of regimen, gender or type of malignancy. In a prospective study 50 children suffering from different malignancies ad-mitted in pediatric oncology department of Besat Hospital of Sanandaj in 2010-2012, under ANTs regimen (Daunorubicin, Doxorubicin) in doses lower than 350 mg/m2 were followed by serial echocardiography for 1-3 years. The deviation from normal values of echocardiographic parameters was measured for all patients in this period and even one parameter's deviation was considered as cardiac dysfunction and ANTs cardi-otoxicity. The association of this toxicity and probable risk factors was analyzed by proper statistical methods in SPSS 18th version. In 22% of patients, mostly children older than 11, at least one of echocardio-graphic parameters including: ejection fraction (EF), left ventricular end systolic diame-ter (LVESD), left ventricular end diastolic diameter (LVEDD), left ventricular mass (LVM) and left ventricular posterior wall diameter (LVPWD) changed during our follow up. The most important risk factor for cardiotoxicity in this study was age at beginning of ANTs regimen. Acute myeloid leukemia (AML) had the most abnormal values among all types of malignancies. In this study there was no statistically significant as-sociation between cardiotoxicity and gender or duration of follow up. Anthracyclines even in doses lower than 350 mg/m2 can induce cardiac dysfunction and alter echocardiographic parameters, although these changes are not always accompanied by clinical signs or symptoms as they were in this study. So long term echocardiographic follow up and cardioprotective techniques are recommended in prescription any doses of these cardiotoxic drugs.