Evaluation of cardiac toxicity of idarubicin (4-demethoxydaunorubicin)

Cardiac toxicity of idarubicin (4-demethoxydaunorubicin), a new daunorubicin derivative, was tested in 49 phase II patients with advanced malignancies. In 26 patients the drug was given intravenously at a dose of 13 mg/m² and in 23 orally at a dose of 45 mg/m². Cardiac toxicity was evaluated by means of electrocardiography, left ventricular systolic time intervals, echocardiography and radionuclide cineangiography. The type and incidence of ECG abnormalities were comparable to those observed with other anthracycline analogs. Other functional parameters, serially measured to evaluate delayed cardiotoxicity in patients who received more than 65 mg/m² intravenously or 225 mg/m² orally, were not significantly different from pretreatment values. No patient developed clinical congestive heart failure. Only one patient exhibited a drop in the left ventricular ejection fraction of more than 15% from pretreatment values. These data indicate that idarubicin given orally or intravenously at the tested doses has no significant cardiotoxic activity in the range of the cumulative doses attained.