The late consequences of anthracycline treatment on left ventricular function after treatment for childhood cancer

Abstract

The purpose of this study was to determine the incidence of changes in left ventricular function in patients in long-term remission after treatment with anthracyclines for a childhood malignancy. The authors examined 155 patients in disease remission who underwent treatment protocols utilising anthracyclines in childhood. The group comprised 90 males and 65 females aged 15+/-4.9 years (range 5-29 years, median 15 years). The age at the time of diagnosis and start of treatment was 8.6+/-4.9 years (range 1-18 years, median 8 years). The time of follow-up was 7.3+/-4 years (range 1-21 years, median 6.3 years). The patients were given a cumulative dose of doxorubicin or daunorubicin of 250+/-131 mg/m2 (range 50-1200 mg/m2, median 240 mg/m2). The values of ejection fraction below 55% and fractional shortening below 30% assessed by means of echocardiography were considered as pathological. The control group consisted of 41 volunteers. Pathological values of fractional shortening were found in 12 patients (8%). Only one patient (0.64%) showed the development of heart failure due to cardiomyopathy. The group of the patients after chemotherapy revealed significantly worse values of left ventricular endsystolic wall stress, mean velocity of circumferential fibre shortening, Tei index, and isovolumic relaxation period in comparison with the control group. We found a correlation between the given cumulative dose of anthracyclines and indicators of systolic function of the left ventricle, but not a relation to the time indicators (age at diagnosis, time of follow-up).

Conclusion: in the mean period of 6 years after chemotherapy, subclinical cardiotoxicity was found in 11 patients (7%) and cardiomyopathy with heart failure in one patient. Further indicators of subclinical damage are elevation of afterload (end-systolic stress), impaired relaxation and increased value of the Doppler index of global left ventricular function. Further monitoring and evaluation of the relevant subclinical abnormalities over a longer period of time are needed.