C4: M Mode And Measurements

Question 1

What’s the main benefit of M mode and what does it allow?

Answer 1

Frame rate

Allows us to sleep fast moving structure in real time

Question 2

M mode good for imaging which structures? What are the other benefits of M modal besides fast frame rate?

Answer 2

All valves

Good for correlating electrical and mechanical events and taking precise measurements.

Question 3

Does M mode use 1 or multiple scan lines? How does this compare to a scan probe?

Answer 3

1

Store probe= ~150 scan lines

Question 4

What’s the avg 2D frame rate? What about M mode?

Answer 4

30-70 FPS

M mode= 1800 FPS

Question 5

How does M mode temporal resolution compare to 2D?

Answer 5

Much higher

Question 6

What are the 3 levels that we use M mode for?

What additional structure do we M mode and in what view?

Answer 6

Aorta and LA
MV
LV base

Tricuspid annulus in the apical 4 chamber view

Question 7

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?

Answer 7

Must be perpendicular to the structure.

…. you’ll over estimate the value of every measurement

Question 8

Purpose of doing an AV and LA m mode tracing?

Answer 8

Looking at:

AO root wall motion
LA size
LA in systole (enlarged?)
AV cusp morphology (thickening) and excursion (opening)

Question 9

How should the cursor line be aligned when doing an M mode of the AV/LA?

Answer 9

Transecting through the AV cusps and parallel to AV valve plane

Question 10

Describe the structures seen in the AV/LA tracing

Answer 10

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

Question 11

What should the ratio of the AV and LA side be?

Answer 11

1:1 ratio

Question 12

Is the AO valve box harder to get when the valves are thin?

Answer 12

Yes

Question 13

Which cusp is which for the AO valves in the M mode tracing?

Answer 13

Anterior is the RCC

Posterior is the Non-CC

Question 14

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?

Answer 14

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

Question 15

Why do we do M mode of the MV?

Answer 15

Look for MV morphology, asses its motion

Assess for AV leak which would effect movement of MV

Assess LV systolic function

Question 16

What does EPSS stand for? What is it & what does it mean if the value is increased?

Answer 16

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

Question 17

What does a brighter m mode tracing indicate

Answer 17

Valvular stenosis

Question 18

Why do we do an m mode of the LV base?

Answer 18

To asses LV wall motion

Calculate EF & FS

assess for wall motion abnormalities of the IVS

Question 19

Which measurements of the LV do we do in M mode?

And at what time in the cardiac cycle?

Answer 19

IVS
LVIDd
LVPW
End diastole

LVIDs
End systole

Question 20

How can you tell the difference between the chordae and the LVPW on m mode of the LV?

Answer 20

The posterior wall should have the steepest upward slope

Question 21

How do the chordae appear on m mode?

Answer 21

Horizontal lines, most often seen in end systole

Question 22

What do LVEDD and LVESD stand for? What measurements are they equal to

Answer 22

LVEDD: LV end diastolic dimension
Same as LVIDd

LVESD: LV end systolic dimension
Same as LVIDs

Question 23

Why do we do an m mode of the PV?

Answer 23

Can be used to diagnose pulmonary hypertension

Question 24

How could we tell if the patient has pulmonary hypertension from the PV m mode?

Answer 24

There will be no A wave with pulmonary hypertension

Question 25

Whats an advantage of anatomical m mode?

Answer 25

Can correct for poor alignment to a structure by crossing over multiple scan lines

Question 26

What does TAPSE stand for and what do we used it for?

Answer 26

Tricuspid annular plane systolic excursion

Assesses the systolic function of the RV in the A4CH view by measuring the movement of the TV

Question 27

In a norm RV, how much should the TV annulus be moving away and towards the apex?

how should the curser be place?

Answer 27

> 17mm

Curser should be transecting through the lateral tricuspid valve annulus