Early cardiac toxicity of 4′-iodo-4′-deoxydoxorubicin

4′-iodo-4′-deoxydoxorubicin was administered intravenously to 35 patients with advanced malignant neoplasms. The doses were escalated as follows: 2, 4, 6, 7, 10, 14, 19, 26, 52, 70, 80 and 90 mg/m². Myocardial function was assessed by Holter monitoring and echocardiography. The prevalence of arrhythmias that could be attributed to the drug in the 24 h following infusion was 14.3% (supraventricular) and 10.6% (ventricular). Echocardiographic heart function variables were unchanged at 24 h and 21 days from drug injection. The data indicate the absence of significant, acute cardiotoxic effects of 4′-iodo-4′-deoxydoxorubicin.