Introduction: The authors used echocardiography at rest and dynamic stress echocardiography to assess left ventricular function in asymptomatic patients treated during childhood or adolescence by chemotherapy containing anthracyclines. Material and methods: 137 patients were examined (81 men, 56 women) aged 16.6 ± 4.8 years (median 17 years) where at the age of 9.1 ± 4.8 years(median 9 years)malignant disease was detected and treatment with a cumulative dose of anthracyclines 242 ± 110 mg/ m2 (median 240 mg/ m2) was administered. The control group was formed by 30 subjects (14 men, 16 women) aged 19.5 ± 5.2 years (median 20 years). The echocardiographic examination was made at rest and immediately after a dynamic stress on an ergometer with a load of 25 W/2 mins. Results: In 8 % patients (n = 11) a reduction of the fractional shortening (FS) LV < 30 % was found. The values of the ejection fraction (EF), the median shortening of the circumferential fibre and endsystolic wall stress, excursion and thickening of the posterior wall of the LV were significantly worse as compared with the group with fractional shortening > 30 % and the control group. The maximum drop of EF was to 40 % and of FS to 20 %. The values of the index of the global LV function (according to Teie) were as compared with the control group worse in both sub-groups of patients. No differences were found in the exercise tolerance between groups. Values of the ejection fraction at rest and after a exercise were in the sub-group with FS < 30 % significantly lower as compared with the others. The values of the stress increment of EF were elevated in all subgroups. In none of the subjects the load caused a decline of the EF. Conclusions: Chemotherapy with anthracyclines leads to a late disorder of several indicators of left ventricular function. Asymptomatic patients with a drop of the EF value to 40% or FS to 20 % preserve their load tolerance and contraction reserve of the left vetricle. The finding of a preserved contraction reserve and good exercise tolerance implies a more favourable prognosis of the patient. Echocardiography at rest should be made repeatedly after treatment, in case of a pathological finding a loading test must be indicated to evaluate the contraction reserve and its possible development.

        Key words: Dynamic stress echocardiography - Cardiotoxicity - Anthracyclines