Echocardiography for Evaluation of Oncology Therapy-Related Cardiotoxicity.

Advances in cancer therapy have improved the outcomes and survival rate of oncology patients. 1 As patient survival is extended, early detection and in-time intervention of therapy-related cardiotoxicity are becoming increasingly important. The cardiotoxicity varies by the type of treatment utilized and the mechanisms of cardiac damage involved. 2 Type 1 cardiotoxicity is caused by the notorious anthracyclines with cumulative dose effects. 3 Anthracyclines such as doxorubicin and epirubicin inhibit topoisomerase II in cardiomyocytes and induce deoxyribonucleic acid double strand breaks and transcription changes. 3 The myocardial damage caused by such type 1 agents is often permanent and irreversible. Patients who are treated with type 1 agents are at an increased risk for significant myocardial dysfunction, subsequent heart failure and death during the followup. Type 2 cardiotoxicity is typically caused by targettherapy agents such as trastuzumab. 3 Here, trastuzumab blocks human epidermal growth factor receptor 2 (HER2), expressed on cardiomyocytes in addition to tumor cells, leading to the loss of HER-2 – mediated survival pathways. 4 There is no cumulative dose effect and the cardiotoxicity is likely to recover after drug withdrawal. 3