Cardiac morphologic and functional changes induced by epirubicin chemotherapy

Cardiac toxicity was evaluated in 24 patients who received epirubicin as a single chemotherapeutic agent, in doses of either 30 mg/m2 every week (11 patients) or 90 mg/m2 every 3 weeks (13 patients). The total doses of epirubicin ranged from 180 mg/m2 to 918 mg/m2 (mean, 491 +/- 187). No patient had prior heart disease, hypertension, mediastinal irradiation, or chemotherapy with other anthracycline agents. None of the patients developed overt heart failure, significant arrhythmias, ECG alterations, or roentgenographic changes in heart size. There was no significant change in the mean value of echocardiographic percent fractional shortening before and after epirubicin therapy. Patients receiving epirubicin doses less than 450 mg/m2 had minimal hemodynamic disturbances; however, no cut-off point separating two significantly different subpopulations could be demonstrated. Endomyocardial biopsy was performed on all patients; 20 biopsies were evaluable. Histologic and ultrastructural changes were similar to those caused by other anthracycline agents. A strong correlation was demonstrated between total dose of epirubicin and pathologic change as quantified using the Billingham scale (r = .7, P = .0006). A cut-off point beyond which there was a probability of increased pathologic damage was statistically defined at 450 mg/m2 of epirubicin. Severe pathologic alterations and moderate hemodynamic changes were observed in only one patient, who received 918 mg/m2 of epirubicin. Patients who are expected to receive epirubicin in excess of 450 mg/m2 should be monitored for cardiac toxicity, and continuation of epirubicin therapy beyond 900 mg/m2 should be based on the results of monitoring.