In order to establish which indices of early diastolic function obtained by Doppler echocardiography and the time/activity curve of 99mTc radionuclide angiography are the most useful clinically, the two investigations were performed in 41 subjects aged 52 +/- 15 years. The maximum velocity of LV filling and mitral E wave provided the best correlation (r = 0.48); the Doppler A wave did not correlate with its scintigraphic homologue. The correlations with the morphological data (mass, thickness/radius ratio) were better with radionuclide angiography. Variance analysis of E and maximum velocity of filling showed that gamma angiography was significantly more accurate (FE LVF greater than 10 p = 10 - 4); on the other hand, the A wave best illustrated the transfer of filling to late diastole. In conclusion, left ventricular filling may be assessed clinically by Doppler echocardiography; the greater accuracy of the radionuclide measurements with respect to left ventricular volumes makes this a more appropriate method when quantitative information is required.