[Chemotherapy and cardiotoxicity]

Among the various anticancer drugs, used alone or in combination during courses of chemotherapy, anthracyclines (leader: doxorubicin) are responsible for direct myocardial toxicity, which can exceptionally be acute, but more often chronic with a delayed onset. This cardiotoxicity is directly proportional to the cumulative dose administered and the recommended total dose for doxorubicin is 550 mg/m2. The risk factors able to potentiate cardiotoxicity must be analysed before starting chemotherapy and follow-up by ultrasonography and/or isotope ejection fraction must be repeated before each course. The treatment of anthracycline-induced heart failure consists of digitalis alkaloids combined with angiotensin converting enzyme inhibitors. The cardiac toxicity of 5FU is currently explained by the theory of coronary spasm, based on clinical findings such as chest pain associated with ischaemic electrical modifications. The incidence of this toxicity is low, but it can be fatal. Exceptional examples include the cardiotoxicity induced by high-dose cyclophosphamide responsible for acute haemorrhagic myocarditis, potentiation of the cardiotoxic effect of anthracyclines by dacarbazine and plicamycin, and serious ventricular and supraventricular arrhythmias induced by amsacrine. Among the various cytokines used in oncology, interferon is responsible for heart failure, reversible after stopping treatment, but also for ventricular arrhythmias, or even sudden death, the pathophysiology of which still remains unclear.