Anthracyclines are antitumoral agents whose therapeutic efficacy is limited by dose-dependent cardiotoxicity. Thirty-one adult patients treated with long-term anthracycline were included in a prospective study to evaluate the ejection fraction and certain parameters of left ventricular diastoclic function by radionuclide angiography, and the left ventricular phase by Fourier's method. Scintigraphic acquisitions were obtained before starting and four weeks after ending chemotherapy. A significant decrease in the maximal velocity of early diastolic filling (2.84 +/- 0.57 to 2.49 +/- 0.45 VTD/s; p < 0.01), the ejection fraction also fell from 57.6% +/- 4.7% to 53.8% +/- 4.6% (p < 0.01). No significant changes in early diastolic filling time or analysis of left ventricular phase with respect to standard deviation (p > 0.05) were observed. In addition, the change in maximal velocity of early diastolic filling did not correlate with the reduction in ejection fraction. Therefore, left ventricular diastolic dysfunction is probably an early marker for anthracycline cardiotoxicity, the sensitivity of which is close to that of the ejection fraction in the detection of infraclinical cardiotoxicity.