High Yield PTEeXAM Review Part 1 & 2 (a-c) Flashcards
How does color M-mode flow propagation velocity (Vp) change with preload in all patients?
Increases Vp with increases in preload in all patients
(Sensitive with loading conditions)
Is the mitral annular tissue doppler early velocity (e’) load dependent or load independent?
Is this for all patients, or selected only for diastolic dysfunction?
Load independent
Only in patients with diastolic dysfunction
What is the normal e’ velocity?
e’ >10 cm/sec
When is E/e’ unreliable?
Normal patients
What is seen here?
Septal Tricuspid Valve Leaflet
What is the most load independent of systolic function?
End Systolic Elastance
Other than End-Systolic elastance, name 3 other relatively load independent indexes of contractility.
1. Preload recuitable stroke work
2. Strain rate
3. Preload adjusted max power
What is the end systolic elastance?
The slope of a line through the end-systolic pressure-volume point (the left upper corner of the P-V loop) is termed End-Systolic Elastance (Ees) and is a measure of ventricular contractility.
What is the slope of the line where you have
Y-axis = Stroke Work
X-axis = End Diastolic Volume
Preload Recruitable Stroke Work = True Index of contractility
Y-axis = Stroke Work
X-axis = End Diastolic Volume
What is the formula for Preload Adjusted Max Power?
(Hint; There are 2 of them)
Preload Adjusted Max Power = Stroke Work / EDV2
Preload Adjusted Max Power = Stroke Work / EDA(3/2)
Preload Adjusted Max Power
Load dependent or load independent?
Load independent
How do you obtain tissue doppler peak systolic velocity?
Put PWD gate on the lateral annulus of the 4 chamber view
What are the 4 measures of systolic function that are load independent?
- End Systolic Elastance
- Preload Recruitable Stroke Work
- Strain Rate
- Preload Adjusted Max Power
What is the formula for Strain?
Strain = (L2-L1) / L1
What is the formula for Strain Rate?
Strain / Change in time = [(L2-L1) / L1] / Change in time
How do you logistically measure strain ratae of the LV on Echo?
Measure V1 Tissue Doppler
Measure V2 Tissue Doppler
measure “x” = Distance between the 2 velocities
Is speckle tracking angle independent or dependent?
Speckle Tracking = Angle Independent
What is strain rate dependent on?
(Reason why people don’t use this)
Angle
What is the normal value for strain rate of the LV or RV?
Anything more negative than -20.
Anything that is “more positive” than -20, is abnormal
What is this?
Papillary Fibroelastoma
Where do fibroelastomas develop (Be specific)?
Downstream side of the Valve
(LV side of the MV or Aortic side of the AV)
What is the function of the backing material in an ultrasound transducer?
Decreases the quality factor
Draw an ultrasound transducer with these three pieces of equipment.
1. Backing material
2. Matching Layer
3. Piezoelectric Crystal
Matching layer in front
PZT crytals behind
Backing material in back of that
What is the Q factor?
Unitless number that represents the transducers ability to emit a clean ultrasound pulse with a narrow bandwidth
What is the Q factor formula?
Resonance frequency / Bandwidth
What is the optimal thickness of matching layer to the wavelength?
1/4 of wavelength thickness
What is the purpose of the matching layer?
Facilitates transfer of ultrasound through the tissues
Prevents a large echo interface of the transducer and the body
What is the optimal thickness of the crystal relative to the wavelength?
1/2 of wavelength
How does the backing material improve axial resolution
- Functions to shorten SPL (Shorter pulse)
Prevents excess vibration of the crystals
- Less vibration = Shorter SPL = Improved axial resolution
- Equation Axial resolution = 1/2 SPL therefore if you decrease this, you improve axial resolution
Decreases ringing of the crystal
“Cloth that covers a wine glass” - DINGGGGGGG
then you grab it with a cloth
What material is the piezoelectric crystal made out of ?
Lead Zirconate Titanate
What is the piezoelectric effect?
Conversion of sound to electrical signal
What is the reverse piezoelectric effect?
Conversion of electrical signal to sound
What is another term for backing material?
Damping element
What is bandwidth of an ultrasound?
Range, or differences between the highest and lowest frequencies in the pulse
A transducer has a main frequency of 5 MHz. The range of frequncies is from 2 to 8 MHz.
What is the bandwith?
Bandwidth = 8-2 MHz = 6 MHz
How does the backing material affect:
- Bandwidth
- Q factor?
Higher bandwidth
Lower Q factor
What is a duty factor?
And relate it to an drawing illustration.
Fraction of time which an ultrasound transmits a wave
Ex: CWD Duty factor = 100%
What is the expected Mitral E/A Ratio for :
Normal diastolic function?
>/= 0.8
What is the expected Mitral E/A Ratio for :
Grade I diastolic dysfunction?
= 0.8
What is the expected Mitral E/A Ratio for :
Grade II diastolic dysfunction?
>0.8 to <2
What is the expected Mitral E/A Ratio for :
Grade 3 diastolic dysfunction?
>2
What is the expected E/e’ for :
Normal Diastology Function?
< 10
What is the expected E/e’ for :
Grade 1 Diastology Dysfunction?
<10 e/e’
What is the expected E/e’ for :
Grade II Diastolic Dysfunction?
10 - 14
What is the expected E/e’ for :
Grade III Diastology Dysfunction?
>14
What is the expected Peak TR Velocity (m/sec) for :
Normal Diastology Function?
< 2.8 m/s
What is the expected Peak TR Velocity (m/sec) for :
Grade I Diastolic Dysfunction?
< 2.8 m/sec
What is the expected Peak TR Velocity (m/sec) for :
Grade II Diastolic Dysfunction?
> 2.8 m/sec
What is the expected Peak TR Velocity (m/sec) for :
Grade III Diastolic Dysfunction?
> 2.8 m/s
What is a normal deceleration time for normal diastolic dysfunction?
<220 ms
What is a deceleration time for Grade I Diastolic Dysfunction?
>220 ms
What is a deceleration time for Grade II Diastolic Dysfunction?
150 - 200 ms
What is a deceleration time for Grade III Diastolic Dysfunction?
<150 ms
