C4: M Mode And Measurements Flashcards
What’s the main benefit of M mode and what does it allow?
Frame rate
Allows us to sleep fast moving structure in real time
M mode good for imaging which structures? What are the other benefits of M modal besides fast frame rate?
All valves
Good for correlating electrical and mechanical events and taking precise measurements.
Does M mode use 1 or multiple scan lines? How does this compare to a scan probe?
1
Store probe= ~150 scan lines
What’s the avg 2D frame rate? What about M mode?
30-70 FPS
M mode= 1800 FPS
How does M mode temporal resolution compare to 2D?
Much higher
What are the 3 levels that we use M mode for?
What additional structure do we M mode and in what view?
Aorta and LA
MV
LV base
Tricuspid annulus in the apical 4 chamber view
how must the sound beam be hitting the structure of interest when doing and M mode tracing?
What will happen if you aren’t perpendicular to the structure?
Must be perpendicular to the structure.
…. you’ll over estimate the value of every measurement
Purpose of doing an AV and LA m mode tracing?
Looking at:
AO root wall motion
LA size
LA in systole (enlarged?)
AV cusp morphology (thickening) and excursion (opening)
How should the cursor line be aligned when doing an M mode of the AV/LA?
Transecting through the AV cusps and parallel to AV valve plane
Describe the structures seen in the AV/LA tracing
Box is the opening of the AO leaflets
Horizontal line in the closure of the AO leaflets
Top bright line is the Anterior wall of the AO root
Bottom bright line is the posterior wall of the AO root
Black Space below the posterior wall of the Ao root is the LA… posterior wall of LA is below this space
What should the ratio of the AV and LA side be?
1:1 ratio
Is the AO valve box harder to get when the valves are thin?
Yes
Which cusp is which for the AO valves in the M mode tracing?
Anterior is the RCC
Posterior is the Non-CC
Which 2 measurements are done on the AV Mmode? When in the cardiac cycle are these structures measured?
And where would you put the calipers?
1: AO root
Measure in end diastole
(Before the AO box)
2: LA
Measure in end systole (at the end of the AO box)
Measure both leading to leading edge
Why do we do M mode of the MV?
Look for MV morphology, asses its motion
Assess for AV leak which would effect movement of MV
Assess LV systolic function
What does EPSS stand for? What is it & what does it mean if the value is increased?
End point to septal separation
Distance between the MV and the IVS when MV is open
It means the LV is dilated which occurs with disease
What does a brighter m mode tracing indicate
Valvular stenosis
Why do we do an m mode of the LV base?
To asses LV wall motion
Calculate EF & FS
assess for wall motion abnormalities of the IVS
Which measurements of the LV do we do in M mode?
And at what time in the cardiac cycle?
IVS
LVIDd
LVPW
End diastole
LVIDs
End systole
How can you tell the difference between the chordae and the LVPW on m mode of the LV?
The posterior wall should have the steepest upward slope
How do the chordae appear on m mode?
Horizontal lines, most often seen in end systole
What do LVEDD and LVESD stand for? What measurements are they equal to
LVEDD: LV end diastolic dimension
Same as LVIDd
LVESD: LV end systolic dimension
Same as LVIDs
Why do we do an m mode of the PV?
Can be used to diagnose pulmonary hypertension
How could we tell if the patient has pulmonary hypertension from the PV m mode?
There will be no A wave with pulmonary hypertension
Whats an advantage of anatomical m mode?
Can correct for poor alignment to a structure by crossing over multiple scan lines
What does TAPSE stand for and what do we used it for?
Tricuspid annular plane systolic excursion
Assesses the systolic function of the RV in the A4CH view by measuring the movement of the TV
In a norm RV, how much should the TV annulus be moving away and towards the apex?
how should the curser be place?
> 17mm
Curser should be transecting through the lateral tricuspid valve annulus
