Early detection of anthracycline induced cardiotoxicity

Abstract

Background: Anthracyclines are highly effective chemotherapy agents which have revolutionised the treatment of breast and haematological malignancies. However, one of the well-recognised associated risks with their use is dose-dependent cardiotoxicity which can lead to heart failure and poor prognosis. So far, most studies have focussed on the effects of anthracyclines on the left ventricle (LV) with relatively little known regarding the other cardiac chambers. Aims and Methods: The purpose of this thesis was to assess the effects of anthracyclines on all four cardiac chambers using 2-dimensional echocardiography and speckle tracking echocardiography (STE) alongside measurement of cardiac biomarkers. Patients with a new diagnosis of lymphoma or breast cancer undergoing anthracycline chemotherapy were included in two separate studies conducted for the purpose of this thesis. In the retrospective study, echocardiograms that were performed at baseline (T0), mid-chemotherapy (T1) and post completion of chemotherapy (T2) were analysed. In the prospective study, echocardiograms were performed at baseline (V1) and 1-month post completion of chemotherapy (V2). High sensitivity troponin T (hs-cTnT) was measured at different time points. Results: A total number of 106 patients were included in this thesis. Amongst all the echocardiographic measures obtained, LV global longitudinal strain (GLS) and RV free wall strain (FWS) were the only two measures to demonstrate a consistent decline during treatment. However, in contrary to previously published data, a reduction in LV GLS was not seen to precede a decline in LVEF. hs-cTnT levels showed an increase from the V1 to V2 in all patients and these changes were statistically significant in patients with reduced LVEF and good LVEF. Conclusion: Adverse effects of anthracyclines are not solely confined to the left ventricle. Comprehensive assessment of all cardiac chambers with particular focus on the left and right ventricles should be taken into consideration during the assessment of patients undergoing chemotherapy treatment