0534: Utility of research of the QT/QT-c intervals dispersion and cardiac biomarkers for early diagnosis of anthracycline induced cardiotoxicity in children

Abstract

To establish the usefulness of research of dispersion QT / QTc intervals and values of cardiac biomarkers- B natriuretic peptide (BNP) and troponin (cTnI) for early detection of cardiotoxicity in children with malignancies. Patients: 46 children (2 months-18 years), treated with anthracyclines for malignancies. Control group: 20 healthy children without cardiovascular history. Patients and controls were evaluated by clinical exam, surface 12 lead ECG (3 consecutive cycles of measuring the QT/QTc intervals and QT/QTc intervals dispersion), Doppler echocardiography(echo), determining plasma levels of cardiac biomarkers BNP and cTnI. Significant changes of the parameters in patients compared with controls: – increasing the dispersion of the QT / QTc intervals (73% of cases, especially those with a cumulative dose of anthracyclines >250mg/m 2 and in patients with echo changes induced by anthracycline cardiotoxicity, even only with LV diastolic dysfunction: • the mean of QT dispersion: 80 miliseconds in patients-40 millisec in controls; • the mean QTc dispersion: 87,103 millisec. in patients-55.47 millisec in controls; – increased plasma levels of BNP in 45.7% of patients, to value 240 ng/ml increasing cTnI values plasma at 4.34% of cases. Biological changes were correlated in most cases with clinical manifestations, echo changes induced cardiotoxicity and increase of dispersion QT/QTc intervals. Increased levels of cardiac biomarkers: BNP and cTnI and of the dispersion of QT/QTc intervals in children treated with anthracyclines±other drugs with cardiotoxic efects positively correlates with installation of the cardiotoxicity with clinical or infraclinical manifestations, constituing an useful indicator for the.cardiotoxicity. Changes in this parameters appeared early than echo changes anthracicline induced cardiotoxicity and is necessary to systematic monitoring these parameters during and after cyto-static treatment.