Anthracyclines are effective chemotherapeutic agents against various malignancies but their therapeutic value is limited by well-known dose-related cardiotoxicity, mainly induced by oxygen free radicals. Left ventricular diastolic and systolic functional abnormalities precede the clinical evidence of cardiotoxicity. The aim of this study was to evaluate the possible cardiotoxicity of epidoxorubicin administered as "high-dose short-term" protocol. Twenty patients (mean age 50.4 +/- 7.9 years) without cardiac disease, affected by advanced breast cancer were studied. All patients were treated with epidoxorubicin as neoadjuvant chemotherapy according to the new protocol "high-dose short-term" (cumulative dose 475.8 +/- 35.6 mg/m2, range 450-600 mg/m2, in 4-6 weeks). The effectiveness of cancer chemotherapy was monitored by clinical evaluation and mammography performed before and after treatment. All patients underwent color Doppler echocardiography and resting radionuclide angiocardiography in baseline condition and 30 +/- 10 days after the last cycle of chemotherapy. All patients showed a significant reduction of tumor lesion after chemotherapy. Left ventricular systolic and diastolic function parameters obtained by echocardiography (fractional shortening 33.1 +/- 4.5% vs 32.4 +/- 4.8%; ejection fraction 63.6 +/- 6.2% vs 62.9 +/- 5.7%; E/A ratio 1.73 +/- 0.64 vs 1.82 +/- 0.67; E wave deceleration time 204 +/- 24.6 ms vs 208.5 +/- 31.7 ms;isovolumetric relaxation time 79 +/- 15.7 ms vs 80 +/- 17.8 ms) and radionuclide angiocardiography (ejection fraction 62.4 +/- 7% vs 61.8 +/- 5.9; peak ejection rate 2.87 +/- 0.44 VTD/s vs 2.74 +/- 0.46 VTD/s; peak filling rate 2.72 +/- 0.54 VTD/s vs 2.6 +/- 0.58 VTD/s) did not show significant changes after treatment. In conclusion, our results suggest that epidoxorubicin administration using the "high-dose short-term" protocol in patients with breast cancer does not induce early significant abnormalities of left ventricular systolic and diastolic function.