 |
| Fig.2.5 |
Appreciation
of the three main features of regurgitant jets described above (i.e.,
abnormal direction, turbulence, high velocity) is crucial to the
success of the Doppler beginner. In addition, it is important to
realize that a regurgitant jet may be directed anywhere within the
spatial volume of the receiving chamber (Fig. 2.5). The jet may
also vary in size from small to large.
 |
| Fig.2.6 |
The spatial location and general size of a jet is best assessed
using PW Doppler echocardiography, even though aliasing invariably
occurs as a result of the high velocities encountered (Fig. 2.6).
This makes recognition of the complete abnormal flow profile of
a regurgitant jet almost impossible by PW Doppler alone. In the
pulsed spectral tracing of aortic insufficiency shown, the spectral
recording is filled from top to bottom in diastole and recognition
of the complete spectral profile is quite difficult.
 |
| Fig.2.7 |
Thus, CW Doppler must be used to record the full contour of
the abnormal regurgitant profile in this same patient (Fig. 2.7).
CW Doppler, in turn, has the disadvantage of lack of depth resolution,
and is therefore not suitable for precisely localizing areas of
turbulent flow in the heart.
2004