Apical Echo and Doppler Flashcards
Standard echo views:
Parasternal
Apical
Subcostal
Suprasternal
The apical views:
apical 4-chamber
apical 5-chamber
apical 2-chamber
apical long-axis(a.k.a. apical 3-chamber)
Views from the apical long axis window are used for
assessment of wall motion
Doppler assessment of valve function
What are you looking at in the Apical window:
Looking at the heart from the lower-left corner of the ribcage: PMI(point of maximal impulse)The apex of the heart is closer to the surface than the base is.
What is your Transducer placement as your home based view:
PMI, with beam-edge indicator toward patient’sLEFT shoulderfor the 4-chamber view(use this as your home-base view)
The heart is upside down?Apex is at the top?
Yes, because the probe is closest to the apex.The convention is to leave the view this way.
How do you get a Apical 5-chamber view:
From the 4-chamber view,lay the probe down toward the patient’s chest a bit, so that the plane includes theaortic root.
The four probe movements:
RockAngleRotateSlideUse them to fix the image.
Slide to
bring the apex to the right or left of the screen (put it in the middle)
Rock to
make the heart vertical(i.e., to move the base of the heart)
Angle to
get the atria backor to get 5-chamber view
Rotate to
open up all four chambersor to move from 4-chamber to 2-chamber, etc.
Looking for two things with Doppler in cardiac work.
- Direction of flow (i.e., regurgitation)
- Velocity (i.e., stenosis)
Smaller opening (stenosis) leads to faster flow: = V x CSA
Doppler angle relative to flow:
90° is the worst
(cosine is 0, and 0 times anything is 0, so no frequency shift)
0° gives the maximum frequency shift possible.
Apical view has valve flow almost directly toward the beam or away from the beam: 0°
(flow is parallel to the Doppler beam)
Which valves have flow toward the beam?
Tricuspid and Mitral valve
Which have flow away from the beam?
Aortic
What if you’re a bit off from 0°?
Not a big problem, since even 30° off = only 5% error in velocity estimate.
Still, try for as close to 0° as possible.
PW has a sample volume (gate):
scanner pays attention only to that one portion of the Doppler beam, ignoring the rest.
CW has a continuous
CW gives you everything along the beam
Can you change the size of the gate?
You can change the size of the gate, though it’s usually best to leave it fairly small for precise evaluation.
In the real world, why what doppler do techs use for the Aortic valve? Why?
techs will often use CW Doppler for the aortic valve, because of the “aliasing” phenomenon that occurs with PW Doppler: PW processing can’t keep up with higher frequencies, so the waveform wraps around the spectral display. This gets worse with more depth and with higher velocities/higher frequency-shifts.
What is flow direction on the spectral display below the baseline?
is away from the beam
for cardiac work-it is different in the vascular lab
What is flow direction on the spectral display above the baseline?
is toward the beam
for cardiac work-it is different in the vascular lab
Remember the flow directions in the heart relative to the Doppler beam! Think which sites are proximal/distal—where flow comes from, where it goes to.
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