To investigate the usefuless of aortic flow velocity spectrum by Doppler echocardiography to assess left ventricular systolic performance, 16 normal subjects, 27 patients with left ventricular hypertrophy(LVH) with hypertension and 21 patients with dilated cardiomyopathy(DCM) were studied.

Peak velocity(PV), peak acceleration(PA), systolic velocity intergral(SVI) and acceleration time/ejection time ratio(AT/ET) were measured form continuous-wave aortic Doppler spectrum.

The results were as followed;

1) The peak velocities, peak accleration, systolic velocity intergrals and AT/ET rarios in ascending aortic blood flow Doppler spectrum were correlated with ejection fraction significantly(r=+0.387, +0.497, +0.609, -0.648, P<0.05). AT, ET, and SVI were higher than those of normal subjects(P<0.005 respectively).

2) In patients with LVH group, PV, PA, and SVI were higher than those of normal subjects(P<0.05). AT, ET, At/ET ratio and ejection fraction were not difference between two groups.

3) In patinets with DCM group, PV, PA SVI and EF were lower than those of normal subjects(all P<0.005). AT and At/ET ratio were significantly prolonged in patient with DCM, as compared with in normal and patients with LVH group(P<0.05).

These results suggested that peak velocity, peak acceleration, systolic velocity integral, and AT/ET ratio on blood flow velocity Doppler spectrum from ascending aorta were useful indicator assessing left ventricular systolic performence.