Eighteen postmenopausal women were examined by Doppler echocardiography before initiation of HRT (T1), then after ten weeks (T2) and one year (T3). This study group was compared with another in which HRT was not used. Flow velocity integral, which correlates with SV, and MA, an indicator of cardiac contractility, were calculated. In the study group, PFV was 107 +/- 18 cm/s at T1 and increased significantly at T2 and T3. Ejection time, which was prolonged at T2 compared to T1, returned to its basal value at T3. Flow velocity integral increased at T2, but this change was only partially sustained at T3. Mean acceleration maintained its increase throughout T2 to T3. None of the Doppler parameters showed a significant change in the controls from T1 to T3. Our results suggest that the peripheral hemodynamic effects of HRT, such as vasodilatation, are transient, whereas the central effects (increased inotropism) are long-lasting.