Module 6 : PLAX Color and Spectral Doppler

Question 1

why do you we take the specific order of pictures (2D, Color, Spectral)

Answer 1

• 2D = images the structures
• Color = tells if leaking or stenotic (qualitative)
• Spectral = both quantifies normal and abnormal flows in the hear (quantitative)

Question 2

Use of doppler in PLAX

Answer 2

• 2D as normal
• Zoom + Color
  + MV , AV

Question 3

use of doppler in RVIT

Answer 3

• 2D as usual
• Color TV
• CW through the TV

Question 4

why do we zoom on the Mitral valve

Answer 4

• easier to see ruptured chordae
• mitral valve prolapse
• need to see color from annulus to pap muscle
• and leakage/regurge

Question 5

RVIT doppler

Answer 5

• make color box only as wide as the annulus

- assess for regurge

Question 6

tricuspid valve spectral with CW

Answer 6

• measure the peak velocity of the spectral CW trace on the TV
• since velocity is directly proportional to the pressure the modified Bernoulli equation applies

Question 7

modified Bernoulli equation

Answer 7

used to find the pressure gradient

pressure gradient = 4 (V^2)

Question 8

pressure gradient

Answer 8

• difference between an atria and its corresponding ventricle
• use peak velocity
• only can be assessed with CW because PW will alias

Question 9

Right Ventricle Systolic Pressure (RVSP)

Answer 9

• MUST ADD THE RIGHT ATRIAL PRESSURE
  RVSP = 4(V^2) + RAP
  RVSP = SPAP (systolic pulmonary artery pressure) in absence of RV obstruction to outflow

Question 10

What 2 things do we need to calculate the RVSP

Answer 10

• the peak TR velocity

- IVC cine sniff test

Question 11

Right Atrial Pressure RAP

Answer 11

• assessed by performing a sniff test in subcostal 4 chamber view
• we assume the IVC has the same pressure as the right atrium chamber

Question 12

what is the normal response of IVC with sniff test

Answer 12

• IVC should collapse >50%

Question 13

if RA pressure increases how is the IVC affected

Answer 13

• it could be dilated

- non collapsing

Question 14

Calculating the RAP

Answer 14

• assess the IVC diameter is normal or abnormal
• assess if IVC collapsing is normal or abnormal
• use the corresponding value as your RAP

Question 15

NORMAL IVC DIAMETER

Answer 15

= 21mm

Question 16

ABNORMAL IVC DIAMETER

Answer 16

> 21mm

Question 17

NORMAL IVC COLLAPSIBILITY

Answer 17

> 50%

Question 18

ABNORML IVC COLLAPSIBILITY

Answer 18

< 50%

Question 19

RAP for normal IVC diameter and collapsibility

Answer 19

3

Question 20

RAP for normal IVC diameter but abnormal collapsibility

Answer 20

8

Question 21

RAP for abnormal IVC diameter but normal collapsibility

Answer 21

8

Question 22

RAP for abnormal IVC diameter and collapsibility

Answer 22

15

Question 23

2D RVOT PLAX or PSAX

Answer 23

• optimise 2D
• show the pulmonary valve as clearly as possible
• show bifurcation if possible

Question 24

RVOT color doppler

Answer 24

• color box only as wide as annulus
• optimize 2D first
• show pulmonary regurge if there
• can also be done in PSAX
• small amount of regurge is normal
  + looks like candle flame

Question 25

RVOT/PA spectral doppler

Answer 25

- need to show pulmonary regurge AND RVOT/PA outflow | - usually pulsed wave works unless speeds are too high

Question 26

PAT (pulmonary acceleration time)

Answer 26

- aka RVOT - AT - measure with PW sample volume placed in RVOT - how fast from opening of valves to fastest velocity INCREASED PULMONARY PRESSURE DECRESASES PAT

Question 27

NORMAL MPAP MEASUREMENTS

Answer 27

9 - 18 mmHg | OVER 20 IS REALLY BAD

Question 28

wall filter/low velocity reject

Answer 28

- spectral signal should come close to the baseline | - too high of wall filter will block out those echoes losing information