Color-Flow Doppler

Question 1

CF Doppler has eliminated much of the time-consuming search for small insufficient jets with spectral Doppler. It allows proper alignment with all valvular flows, and when properly used, echo interpretations can be made with the added confidence that nothing has been missed.

Answer 1

CF Doppler has eliminated much of the time-consuming search for small insufficient jets with spectral Doppler. It allows proper alignment with all valvular flows, and when properly used, echo interpretations can be made with the added confidence that nothing has been missed.

Question 2

Value of CF gain adjust?

Answer 2

Adjust the system’s sensitivity to received color info. Unlike gain or power controls for 2D imaging, the gain control for CF Doppler does not affect output power, it just affects receiver gain.

Question 3

Increasing the color gain will increase the amount of color shown on the image. When the gain is turned up too high, ………………

Answer 3

Increasing the color gain will increase the amount of color shown on the image. When the gain is turned up too high, speckling or noise will appear throughout the color wedge (speckling is superimposed upon the myocardium).
Fig 3.16
This is different than the mosaic pattern seen with turbulent flow since it is not a discrete jet and is not confined to the blood-filled areas of the heart and vessels. Adjust the gain until just before speckling noise begins to appear.

Question 4

Color sector width and height: This adjust …………………….

Answer 4

This adjust the size of the color wedge.

Question 5

The color sector can be increased to fill the entire real-time sector Reducing the color sector width increase …………..since less time is required to process flow info.

Answer 5

The color sector can be increased to fill the entire real-time sector Reducing the color sector width increase frame rate since less time is required to process flow info.

Question 6

Increasing color width …………… frame rate and reduces the temporal accuracy to color-flow info especially in patients with high heart-rate

Answer 6

Increasing color width decreases frame rate and reduces the temporal accuracy to color-flow info especially in patients with high heart-rate.

The black and white image can be suppressed as well, leaving just the color wedge and the background RT info. Fig 3.16

Question 7

Does changing the height of the color sector affect frame rate?

Answer 7

Changing the height of the color sector usually does not affect frame rate on most machines. It does however eliminate extraneous info above or below the area of interest.

Question 8

The color map allows selection of..?

Answer 8

Selection of reconfigured color flow presentations. (All info in this book will use the blue away and red toward (BART) configuration. Other maps include RABT(red away and blue toward) and pastel maps.

Question 9

Color map:
Turbulent flow may be displayed with either an enhanced or a variance display. The underlying laminar flow is still encoded with a BART display, but the disturbed flow is displayed with different characteristics. An enhanced map encodes ………….

Answer 9

Turbulent flow may be displayed with either an enhanced or a variance display. The underlying laminar flow is still encoded with a BART display, but the disturbed flow is displayed with different characteristics.

An enhanced map encodes the varying velocities of turbulent flow with different colors producing a mosaic or reds, blues, yellows, and cyans.

Question 10

A variance map mixes ……………

Answer 10

A variance map mixes green into the areas of disturbed flow. The result is yellow when green mixes with red and cyan when green mixes with blue.

Question 11

Threshold or tissue priority:
This control assigns the gray level at which color-flow info stops. A high priority for tissue will display very little color. Use the lowest tissue priority in order to get good color filling. A threshold that is too low will cause………………………

Answer 11

This control assigns the gray level at which color-flow info stops. A high priority for tissue will display very little color. Use the lowest tissue priority in order to get good color filling. A threshold that is too low will cause bleeding of color over myocardial structures (Fig 3.18)

Question 12

Color-flow processing:
The way color info is acquired and processed is usually an operator-controlled feature. Each line of color-flow info may be sampled for variable lengths of time.
A large packet size corresponds to a ……………………

The reduced frame rate however may create ……………..

Answer 12

A large packet size corresponds to a longer period of time, decreased frame rate, many color samples, and high quality color.

The reduced frame rate however may create temporal artifacts with the high heart rates of veterinary patient imaging.

Question 13

Color-flow processing:
Medium packet sizes produces faster imaging rates but shorter ……………….. and possibly a lower quality color image. These are generally appropriate for cardiac imaging with average heart rates.

Answer 13

Medium packet sizes produces faster imaging rates but shorter sampling times and possibly a lower quality color image. These are generally appropriate for cardiac imaging with average heart rates.

Question 14

Color-flow processing: Small packet sizes result in the …………….

Answer 14

Small packet sizes result in the fastest frame rates, but very little time is spent gathering flow info.

Question 15

Color-flow processing: Select ………….packet sizes for high quality color images and ……………… packet sizes for higher frame rates and excellent resolution.

Answer 15

Select large packet sizes for high quality color images and medium packet sizes for higher frame rates and excellent resolution.

Question 16

Filters are also an operator-controlled feature of CF processing. Value of filters?

Answer 16

Remove high-intensity, low-velocity info from the image. High filter settings remove most of the low velocity signals are often used to eliminate the strong but low-velcotiy info received from wall and valve motion.

Question 17

Applying a low filter only removes some of the high-intensity signals and so low-flow velocities are seen well.
Cardiac imaging usually requires ………………… setting.

Answer 17

Applying a low filter only removes some of the high-intensity signals and so low-flow velocities are seen well.
Cardiac imaging usually requires medium to large packet sizes and medium to low filter setting.

Question 18

Baseline:
Adjusting the baseline on the color bar allows higher velocities to be displayed in one direction before aliasing occurs. This control is primarily used to…..

Answer 18

to “unwrap” aliased signals.

Fig 3.19

A number at the top and at the bottom of the color bar represents the max detectable velocity before color aliasing occurs. Moving the baseline up or down will double the max detectable velocity for blood flow away or toward the transducer.

Question 19

Persistence of frame averaging:

Persistence averages old sector frame info with new sector frame info in order to display smooth images. This reduces image noise because the equipment’s analyzer assumes the difference between the two frames is mostly noise thus eliminating it from the displayed image. Too much persistence creates…..

Answer 19

Creates a blurred effect, and frame averaging is usually set very low during cardiac exams.

Question 20

Normal color-flow images: Color flow imaging is best done with…..transducers.

Answer 20

Low-frequency

Try a lower frequency transducer if color does not fill the chambers interrogated.

Question 21

CF imaging of the deeper structures in late animals may not be possible (horses etc). How could CF imaging be optimized if a low-frequency transducer is not available.

Answer 21

Decrease 2D sector size, decrease color sector size, increase frame are, increase persistence, decrease tissue priority, and decrease transducer frequency to improve color-flow mapping in large animals and in small animals if a low-frequency transducer is not available.

Question 22

Tipped ……. up imaging planes in both large and small animals improves color flow mapping side flow is more parallel with the Doppler sound beams.

Answer 22

Tipped apex up imaging planes in both large and small animals improves color flow mapping side flow is more parallel with the Doppler sound beams.

Question 23

Aliasing occurs at lower velocities with CF Doppler than with spectral Doppler because of …………………………….

Answer 23

Aliasing occurs at lower velocities with CF Doppler than with spectral Doppler because of the low PRF required.
Normal flow may sometimes have aliased signals as a result. This results in a wrapping around effect where the blues moving away from the transducer are layered with reds after the Nyquist limit is exceeded and red moving toward the transducer in normal flow is layered with blue. The layering is generally seen in the middle of the flow jet while the periphery of the CF profile remains true to its flow direction. Fig 3.20.
Fig 3.21

Question 24

Color aliasing may occur when flow is laminar: use a small color actor to reduce temporal artifacts. Use lower frequency transducers.

Answer 24

Color aliasing may occur when flow is laminar: use a small color actor to reduce temporal artifacts. Use lower frequency transducers.

Question 25

Turbulent flow results in disorganized and greatly variant velocities. When turbulent flow is detected, green is added to the areas of disorganized flow if a …..is used and a blue red yellow white mosaic is seen when using …………….. maps.

Answer 25

When turbulent flow is detected, green is added to the areas of disorganized flow if a variance .is used and a blue red yellow white mosaic is seen when using enhanced maps. This mosaic pattern is easy to detect and is useful in identifying areas of abnormal flow. Low-velocity flows are generally not detected and no color is assigned. These areas will remain black.
Fig 3.22

Question 26

Which view is the best for imaging CF Doppler?

Answer 26

Tipped long-axis (apex up, base down) and apical four and five chamber views.
Fig 3.23
Images that align the interventricular septum horizontally across the sector may produce good color images depending upon depth and transducer frequency however.

Question 27

The color encoded 2D images will be different depending upon the image generated. For ex a tipped view with the apex up will have CF through the heart with exactly the opposite colors of that would be seen if the image were generated with the apex down and base up toward the top right of the sector.

Answer 27

Color flow imaging is usually better with images that align flow in relatively up and down directions.

Question 28

Mitral valve and tricuspid valve flow: Horizontally aligned parasternal long-axis 4 chamber or left ventricular inflow outflow images, and apical 4- and 5 chamber views will show left ventricular inflow through the mitral valve as ……. with a brighter central area.

Answer 28

red

Question 29

Mitral valve and tricuspid valve flow: When the Nyquist limit is exceeded the central area of flow may have a layer of…….. superimposed upon it.

Answer 29

blue

When turbulent flow is detected and it exceeds the Nyquist limit, the disorganized cellular movement creates a mosaic pattern on the CF image.

Figures 3.24, 3.25, 3.26, 3.27.

The same is true for tricuspid flow. 3.28, 3.29, 3.30.

Since in the parasternal images tricuspid flow is not as deep, the Nyquist limit is higher and aliasing will not occur as readily.

Trivial to mild tricupid regurgitation is commonly seen in all animals.
Fig 3.31

Question 30

Aortic flow:
Aortic flow is displayed in hues of blue with ……….. aliasing as blood leaves the LV in a downward direction i the apical 5 ch view.

Answer 30

red
Fig 3.32

The depth of the aorta in this view usually results in a low Nyquist limit and “wrap around” or aliasing is usually seen.

Question 31

Parasternal views of the aorta may have flow mapped as………….. depending upon the angle at which it is aligned with the transducer. Fig 3.33, 3.34 The color usually changes as the aorta curves away from the heart.

Answer 31

either red or blue

Question 32

Pulmonary artery flow encoded upon the transverse image at the base of the heart in either the left or right parasternal views is usually ………….. as blood leaves the right ventricle in a direction away from the transducer.

Answer 32

blue

Because the artery curves in this plane, there is typically layering of colors within the pulmonary artery flow profile (fig 3.35, 3.36).

Question 33

Pulmonary artery flow: Total reversal of color is seen as flow progresses from …….. velocity during early systole to ……. velocity in mid systole to ……….. velocity at the end of systole

Answer 33

Total reversal of color is seen as flow progresses from low velocity during early systole to higher velocity in mid systole to slower velocity at the end of systole (Fig 3.19).

Question 34

Trivial to mild pulmonic insufficiency is often seen in both large and small animals.

Answer 34

Fig 3.37

Question 35

Spectral Doppler: Uses imaging planes that align the sound beam as parallel with the direction of flow as possible. This is the opposite of …………………., which will produce the best 2D images.

Answer 35

This is the opposite of sound beam alignment, which will produce the best 2D images.

Question 36

Remember that sound is reflected directly back to the transducer if it strikes the structure with a 90 grader angle of incidence. Doppler however is dependent upon ………..

Answer 36

dependent upon the angle of incidence in a different manner.

The farther away from parallel to flow the sound beam is, the greater the error introduced into defining the maximum velocity

Apical views are therefore the appropriate views for obtaining flow info for mitral and aortic valves.

Question 37

Parasternal long-axis planes are useful when interrogating the pulmonary artery or at times the tricuspid valve. Valvular insufficiencies are recorded in whatever plane aligns the color-flow jet direction with the spectral Doppler cursor.

Answer 37

Parasternal long-axis planes are useful when interrogating the pulmonary artery or at times the tricuspid valve. Valvular insufficiencies are recorded in whatever plane aligns the color-flow jet direction with the spectral Doppler cursor.

Question 38

When simply determining the presence or absence of a regurgitant jet or stenotic lesion is important, then parasternal images may provide that info. It is possible to interrogate the left atrium for instance from parasternal long-axis images and determine the extent of a regurgitant jet into the atrium.
What about measurement of regurgitant fractions, cardiac output, or pressure gradients?

Answer 38

Regurgitant fractions, cardiac output, or pressure gradients require parallel alignment with flow, and these are the planes described in the following sections

Question 39

Controls: cursor. A cursor is ….

Answer 39

placed along the predicted direct of flow to record velocities. The direction of flow can usually be determined with color-flow Doppler. Without color guidance however, the flow direction must be determined by interrogating the area carefully. Fig 3.38

Question 40

Gate: The gate is represented by a mark on the cursor line and corresponds to the sampling site. Fig 3.39. Its depth can be adjusted along the cursor with a track ball.

Answer 40

The gate is represented by a mark on the cursor line and corresponds to the sampling site. Fig 3.39. Its depth can be adjusted along te cursor with a track ball.

Question 41

Gate size: The …………………. can be adjusted to include more of less area. Increasing the gate size too much will lead to some ambiguity as to exact location of flow info and can introduce too much noise into the signal, but allow small regurgitant jets to be recorded with greater ease.

Answer 41

The sample volume size can be adjusted to include more of less area. Increasing the gate size too much will lead to some ambiguity as to exact location of flow info and can introduce too much noise into the signal, but allow small regurgitant jets to be recorded with greater ease.

Question 42

Angle correction: Value?

Answer 42

Most machines have a separate line originating from the Doppler cursor. Fig 3.38.
This is used to correct for angle when the Doppler cursor cannot be placed parallel to flow.
The equipment will take the angle into account when calculating flow velocity and display the pressure gradient accordingly.

It is always better to try to align the cursor as parallel to flow as possible instead of using the angle correction since flow velocity alignment error in the third dimension can be magnified with angle correction.

Question 43

Baseline: The baseline corresponds to …………. velocity. The gate in PW Doppler is represented by the baseline and flow moves up or down away from zero velocity. The baseline can be shifted up or down to unwrap mildly aliased signals. A baseline positioned at the top of the Doppler spectrum will only display flow ……… from the gate or transducer but at twice the velocity before aliasing occurs. The baseline may also be moved down on the spectrum.

Answer 43

The baseline corresponds to zero velocity. The gate in PW Doppler is represented by the baseline and flow moves up or down away from zero velocity. The baseline can be shifted up or down to unwrap mildly aliased signals. Fig 3.40. A baseline positioned at the top of the Doppler spectrum will only display flow away from the gate or transducer but at twice the velocity before aliasing occurs. The baseline may also be moved down on the spectrum.

Question 44

Aortic flow generally has an aliased signal. Why?

Answer 44

Since the Nyquist limit almost always is exceeded

Question 45

Scale: The range of velocities may be changed in both PW and CW displays. Increasing the scale (…………………………) setting will ……………….. the velocity limits on each side of the baseline and decreasing the scale will ……………. the velocity limits.

Answer 45

The range of velocities may be changed in both PW and CW displays. Increasing the scale (pulse repetion frequency (PRF) setting will increase the velocity limits on each side of the baseline and decreasing the scale will decrease the velocity limits. Fig 3.41

Question 46

The maximum velocity limit (Nyquist limit) in PW Doppler …………….. with lower frequency transducers or …………. sampling depth.

Answer 46

The maximum velocity limit (Nyquist limit) in PW Doppler increases with lower frequency transducers or less sampling depth.

Question 47

Doppler gain: Similar to other gain controls; doppler gain increases or decreases image intensity. Increasing Doppler gain will …………….. the strength of the returning signal.

Answer 47

Similar to other gain controls; doppler gain increases or decreases image intensity. Increasing Doppler gain will increase the strength of the returning signal.

Turn the gain on high enough to be sure a complete envelope is recored, and then turn it down until associated noise and mirror image artifacts are minimized.

Question 48

Early systolic flow mapping within the pulmonary artery generally shows an aliased signal.

Answer 48

Early systolic flow mapping within the pulmonary artery generally shows an aliased signal.

Question 49

Wall filters: Value?

Answer 49

Doppler wall filters decrease the amount of low frequency noise that is recorded from moving structures such as cardiac walls and valves.

Question 50

What happens if the wall filter is turned up too high?

Answer 50

This eliminates the start and end of flow information, which is important in some applications.
Fig 3.42

Question 51

Sweep speed: same control as the one used for M-mode displays of the heart. Doppler signals can sweep across the display monitor at a rate of …?

Answer 51

25, 50, or 100 mm/sec.

Higher sweep speeds are used to measure time intervals with greater accuracy.

Question 52

Normal Doppler flow profiles and technique: Often several planes are available for recording flow, and each should be interrogated to assure the most accurate Doppler recordings. Doppler interrogation should be attempted in as many planes as possible.

Answer 52

Normal Doppler flow profiles and technique: Often several planes are available for recording flow, and each should be interrogated to assure the most accurate Doppler recordings. Doppler interrogation should be attempted in as many planes as possible.

Question 53

The decision to use PW versus CW Doppler depends upon?

Answer 53

The reason for flow interrogation and sometimes on the patient. Recording the highest flow velocity in an aorta or pulmonary artery can be obtained by placing a PW gate in the vessel distal to the valve. If a patient is uncooperative or there is a lot of cardiac motion, then CW Doppler cursor placed in line with flow in the artery will record the highest velocity without having to place a gate accurately.

With PW Doppler if the animal moves and the gate is inadvertently no longer where you think it is, other flow info will be erroneously displayed.
If there is outflow tract obstruction a CW gate will automatically record the highest flow.

A PW gate placed in the outflow tract will define the aliasing point (where obstruction starts) but will not provide max velocity info if the Nyquist limit is exceeded.

Question 54

PW Doppler is always necessary if location is important. This is true of most assessment of …

Answer 54

Diastolic flow and tissue Doppler studies.

Question 55

Always pay attention to where the Doppler cursor is placed. For instance, sometimes CW cursor placed in the aorta will inadvertently also cross over into the LA and record….

Answer 55

Mitral regurgitation flow leading to misleading and confusion info about what you think is aortic flow.

Question 56

Doppler interrogation:

For ………….. info: Use images that align the Doppler beam parallel with flow.

For …………….. info: Parallel alignment with flow is not necessary.

Answer 56

For quantitative info: Use images that align the Doppler beam parallel with flow.

For nonquantitative info: Parallel alignment with flow is not necessary.

Question 57

PW Doppler: Use when? (3)

Answer 57

Use when site specificity is necessary.
Use when flow is confusing.
Use with low velocity flow.

Question 58

CW Doppler: Use when? (2)

Answer 58

Use with high velocity flow.

Use when the animal is moving and the gate does not remain in place.

Question 59

Aortic flow: The optimal plane for recording accurate aortic flow is?

Answer 59

The apical 5-ch view or the subcostal 5-ch view.

The PW Doppler gate is positioned just distal to the aortic valve.
Fig 3.43, 3.44
Fan the transducer in and out of the imaging plane in order to satisfy yourself that the highest velocity is being recorded. Remember that the image seen on the monitor is 2D and the Doppler sound beam must interrogate the third dimension by moving side to side and up and down as you scan the aorta.

Question 60

A foreshortened LV chamber appears to have cursor alignment with flow, but the cursor is actually diagonal to the walls of the aorta. Obtain an apical image that shows an LV length about …….. as width (not possible in severely dilated hearts).

Answer 60

A foreshortened LV chamber appears to have cursor alignment with flow, but the cursor is actually diagonal to the walls of the aorta. Obtain an apical image that shows an LV length about twice as width (not possible in severely dilated hearts).

Question 61

Spectral Doppler: Aortic flow:

Imaging plane: left parasternal apical 5 ch vies
Place the gate distal to the aortic valve

Appearance:
Rapid acceleration
Slower deceleration
Asymmetric appearance
Flow starts toward the end of the QRS complex

Answer 61

Imaging plane: left parasternal apical 5 ch vies
Place the gate distal to the aortic valve

Appearance:
Rapid acceleration
Slower deceleration
Asymmetric appearance
Flow starts toward the end of the QRS complex

Question 62

Aortic flow appearance: Flow is away from the transducer so flow profiles are …….

Answer 62

Aortic flow appearance: Flow is away from the transducer so flow profiles are negative

Question 63

Aortic flow appearance: Flow starts toward the ……. of the QRS complex and ends just …… the T wave.

Answer 63

Aortic flow appearance: Flow starts toward the end of the QRS complex and ends just after the T wave.

Question 64

Aortic flow appearance. There is a ………… acceleration, and peak velocity is reahed within the first ……of systole.

Answer 64

Aortic flow appearance. There is a rapid acceleration, and peak velocity is reahed within the first third of systole.
There is very little spectral broadening with PW Doppler until just after peak velocity is reached.

Question 65

Aortic flow appearance: Flow decelerates ………… than it accelerated, giving the aortic flow profile an asymmetric appearance.

Answer 65

Flow decelerates slower than it accelerated, giving the aortic flow profile an asymmetric appearance.

Question 66

Aortic flow appearance: Sometimes diastolic upward flow is seen, and this is probably ………….. …………………….

Answer 66

Sometimes diastolic upward flow is seen, and this is probably mitral flow as the annulus moves toward the gate during contraction.

Question 67

Left ventricular outflow tract flow:

Imaging plane used: Flow within the LV outflow tract also uses….?

Answer 67

Apical 5 ch plane.

The gate is positioned just proximal to the aortic valve between the ventricular septum and the open anterior mitral valve leaflet.

If a discrete or dynamic subvalvular obstruction is suspect, move the gate up and down the outflow tract in order to record and localize any aliased signals.

Question 68

Left ventricular outflow tract flow:

Flow appearance?

Answer 68

Outflow tract flow profiles are negative and similar in appearance to aortic flow except that velocities are lower.
Neg and pos flow can be seen during diastole depending upon the gate position with respect to mitral inflow.

Question 69

Left ventricular outflow tract flow:
Flow appearance:
The further the gate moves away from the aortic valve the more …………. mitral flow is seen.

Answer 69

The further the gate moves away from the aortic valve the more upward mitral flow is seen.

Question 70

Pulmonary artery flow: Imaging plane used.

Pulmonary flow may be recorded from the…..?

Answer 70

1. Right parasternal oblique (modified) long-axis inflow outflow view of the LV with pulmonary artery view
2. Left parasternal short-axis plane with aorta and pulmonary artery,

or

3. Left parasternal cranial long-axis right ventricular outflow view.

Place the gate distal to the valve.

Fig 3.46.

Question 71

Pulmonary artery flow: Appearance?

Answer 71

Negative blood flow (away from the transducer)
Flow starts towed the end of the QRS complex and continues through the T wave.
Acceleration time is slower than in the aorta, and peak velocity is reached about midway during ejection.
Symmetrical and rounded profile
As with aortic flow: spectral broadening does not occur until after peak velocity ha been reached and flow begin to decelerate.

Question 72

A good way to distinguish normal aortic from normal pulmonary flow on still images?

Answer 72

The symmetrical and rounded appearance of the pulmonary flow is different from the aortic flow.

Reduce vascular resistance is thought to be the reason for decreased acceleration time in the plum artery.

Question 73

Right ventricular outflow tract flow:

Which imaging plane should be used?

Answer 73

Any of the three views used to interrogate pulmonary artery flow.

The gate is positioned proximal to the pulmonic valve with the outflow tract between the right ventricular wall and septum

Question 74

Flow appearance: Right ventricular outflow Doppler recordings are similar to pulmonary artery flow except velocities are ……….

Answer 74

Flow appearance: Right ventricular outflow Doppler recordings are similar to pulmonary artery flow except velocities are lower.

Question 75

Transmitral flow: Imaging plane used: Left parasternal apical 4 and 5 ch planes are used to record LV inflow. Fig 3.49. The best flow profiles with highs velocities, least spectral broadening, and good definition to the E and A peaks should be looked for when deciding which imaging plane to use.

Answer 75

Imaging plane used: Left parasternal apical 4 and 5 ch planes are used to record LV inflow. Fig 3.49. The best flow profiles with highs velocities, least spectral broadening, and good definition to the E and A peaks should be looked for when deciding which imaging plane to use.

Question 76

Transmitral flow: Where should the sample gate be placed?

Answer 76

Where the tips of the leaflets when they are wide open. Fig 3.50, 3.51.
Fan the transducer in and out of the imaging plane using CF imaging if necessary until alignment is as good as possible.

Question 77

Transmitral flow: A mitral valve opening click should be clearly heard and a closing click should be barely heard. Lack of an opening sound suggests……. …..while a loud closing sound is usually heard when ………..?

Answer 77

……that the gate is too far into the left ventricle while a loud closing sound is usually heard when the gate is placed too close to the mitral annulus.

Question 78

Transmitral flow: Incorrect placement of the sample gate will alter the mitral flow profile dramatically and create the appearance of …….

Answer 78

diastolic dysfunction.

Question 79

Transmitral flow: Samples placed too close to the mitral annulus will typically decrease ……. velocities and ……….. times.

Answer 79

Samples placed too close to the mitral annulus will typically decrease E velocities and deceleration times.

Question 80

Spectral Doppler: Appearance?

Answer 80

Mitral valve flow profiles are positive and resemble the letter M similar to M-mode images of mitral valve motion. The two phases or inflow are recorded. E is higher than A
Separation of E and A depends upon heart rate.
Positive flow after A is secondary to annular movement.

Fig 3.52

Question 81

PW Doppler should be used to assess mitral inflow profiles. Problems using CW Doppler?

Answer 81

CW Doppler summates the velocities along the beam, and flow profiles do not differentiate between that found at the mitral leaflet tips or at the annulus.

Question 82

E peak corresponds to?

Answer 82

Rapid ventricular filling: oak early diastolic velocity.

Question 83

A peak corresponds to?

Answer 83

Atrial contraction. Upward motion just after the P wave on the ECG.

Question 84

LV inflow stops with onset of …………….. just after the beginning of ………………(ECG)

Answer 84

LV inflow stops with the onset of systole just after the beginning of the QRS complex.

Question 85

Closeness of the E and A peaks is dependent upon ………….

Answer 85

Closeness of the E and A peaks is dependent upon heart rate. Rapid heart rates will create more compact “Ms” and may even cause the two filling phases to overlap, and waveforms will be superimposed. Fig 3.53

This overlap generally will start to appear at HR approaching 125 beats per minute, and complete loss of separation will always be present when HR exceed 200 beats per minute. It is common for transmittal flow profiles in a cat to show summated E and A peaks.

Slow heart rates separate the two peaks dramatically. Fig 3.54

Question 86

The E peak is usually higher than the A peak in normal hearts. This creates an E:A ratio greater than ……..

Answer 86

The E peak is usually higher than the A peak in normal hearts. This creates an E:A ratio greater than one.

Question 87

Positive flow may be seen after the A wave and is thought to be secondary to …….

Answer 87

……. movement of the mitral annulus toward the sternum after the valve closes. This motion pushes blood toward the transducer and is recoded after diastole is conducted.

Question 88

Trans tricuspid flow: Imaging plane used: Can standard right parasternal apical 4 and 5 ch views be used?

Answer 88

Standard right parasternal apical 4 and 5 ch views of the heart usually do not align flow parallel to the Doppler sound beam. This rectified by moving the transducer cranial and dorsal on the thorax until the tricuspid valve is seen opening in an upward direction.

Question 89

Correct alignment of the tricuspid inflow can be seen in …………………….. (3)

Answer 89

1) Left parasternal plane between the apical 4 ch and
the transverse view
2) Left parasternal cranial (heart base) right atrium and auricle view,
3) Left parasternal transverse plane through the heart base.

Fig 3.55

Question 90

Tricuspid inflow: Place the gate at the tips of the tricuspid vale leaflets when they are wide open.

Answer 90

Fig 3.57

Try to obtain flow profiles in all planes and search for the flow profile showing the highest velocities for both phases of inflow with the least spectral broadening.

Question 91

Tricuspid inflow:
….. is usually higher than …… but may be reversed.

Beat to beat changes is velocity due to ………….

Answer 91

E is usually higher than A but may be reversed.

Beat to beat changes is velocity due to respiration.

Rapid ventricular filling phase resulting in an E peak and an A peak associated with atrial contraction as in mitral flow recordings.

Trans tricuspid flow/right ventricular inflow is positive and similar to transmitral flow.

Fig 3.58

Question 92

Inspiration increases peak flow velocities especially the ……. wave, so the E:A ratio increases with ………….. and decreases with ………………….

Answer 92

Inspiration increases peak flow velocities especially the E wave, so the E:A ratio increases with inspiration and decreases with expiration.

Question 93

E/A ratios can be less than ……. for trans tricuspid flow, and positive systolic flow after tricuspid valve closes may be ……. than those seen in transmittal flow tracings.

Answer 93

E/A ratios can be less than one for trans tricuspid flow, and positive systolic flow after the tricuspid valve closes may be greater than those seen in transmittal flow tracings.

Question 94

Pulmonary vein flow: Imaging plane used?

Answer 94

1) Right parasternal transverse images at the level of the left atrium and aorta
2) Right parasternal long-axis images
3) Left parasternal transverse images with left atrium and auricle.
Modified apical 4 ch views.
Fig 3.59

Use whichever plane aligns flow best along the Doppler cursor. This is always obtained using PW Doppler.

Question 95

When using the right parasternal transverse images at the level of the left atrium and aorta; it is important to have a clear view of interatrial septum?

Answer 95

It helps identify caudal vena cava flow on the right atrial side of the septum, which looks very similar to pulmonary venous flow.

Question 96

How can pulmonary venous flow be optimized?

Answer 96

Low tissue priority and low filter settings and low PRF will enhance visualization of this flow.

Tip the crystals up and down and sideways very slightly while on this transverse plane until color evidence of this flow is seen.

Question 97

Pulmonary venous flow: On left parasternal cranial transverse imaging planes: fan the transducer cranial and caudal until the ……is seen

Answer 97

…until the left auricle is seen. The veins will enter the left atrium fro the bottom and to the left side of the chamber.

Use CF imaging to display the veins.

Apical 4 ch imaging planes especially when the left atrium is dilated show the veins well.

Question 98

Pulmonary vein flow:

• Right or left parasternal views
• Lower PRF to appreciate color flow in the vein
• Place PW gate entirely in the vein

Answer 98

• Right or left parasternal views
• Lower PRF to appreciate color flow in the vein
• Place PW gate entirely in the vein

Question 99

Pulmonary venous flow:

Answer 99

The gate is placed entirely in the vein. It should not extend into the LA chamber. Fig 3.59.

Question 100

Flow appearance of the pulmonary venous flow?

Answer 100

Pulsatile and continuous.

Question 101

Most of left atrial filling occurs when?

Answer 101

During ventricular systole when the mitral valve is closed.

This creates a positive deflection on the spectral image, the “S” wave. Fig 3.60

Question 102

Systolic pulmonary venous flow can be biphasic. If it is the early phase, it is labeled ……………., while the second later phase is called …………..

Answer 102

Systolic pulmonary venous flow can be biphasic. If it is the early phase, it is labeled SE (liten nersänkt E9, while the second later phase is called SL (liten nersänkt L).

Question 103

During early diastole, while blood is flowing into the LV ch, there is a drop in LA pressure and blood is passively pulled into the LA as blood moves through the mitral valve into the LV ch.

Answer 103

During early diastole, while blood is flowing into the LV ch, there is a drop in LA pressure and blood is passively pulled into the LA as blood moves through the mitral valve into the LV ch. This phase of LA filling is the “D” wave and is also positive on the spectral image. Fig 3.60.

Question 104

Atrial contraction during the latter part of diastole causes flow to move backward into the veins because?

Answer 104

because there are no valves to prevent this. This A wave is referred to as the A wave, and is negative on the spectral display.
Fig 3.60.

Question 105

Isovolumic relaxation time (IVRT): which time is this?

Answer 105

The time that elapses from the end of ventricular ejection to the time the mitral valves open and diastolic flow into the LV begins. No change in volume occurs, and all valves are closed but pressures decrease and the myocardium relaxes.

Question 106

IVRT: Is recorded by placing a ……. gate or a …….. cursor in the LV outflow tract near the mitral valves and recording a portion of both aortic ejection flow and LV inflow (transmittal flow). Fig 3.61

Answer 106

Is recorded by placing a PW gate or a CW cursor in the LV outflow tract near the mitral valves and recording a portion of both aortic ejection flow and LV inflow (transmittal flow). Fig 3.61

Question 107

Which image views should be used?

Answer 107

1) Oblique modified left apical 4 2) or -5 ch views

that allow the cursor to cross over portions of the mitral valve and the LV outflow tract are ideal

Question 108

Which time interval corresponds to the IVRT?

Answer 108

The time interval from cessation of aortic flow to the beginning of mitral inflow.
Fig 3.62

Left ventricular inflow cannot begin until LV pressure crops below left atrial pressure and the mitral valve can open.

Question 109

IVRT: With the spectral baseline in the middle of the spectral image, ………….. aortic flow and …………….. transmittal flow should be seen.

Answer 109

With the spectral baseline in the middle of the spectral image, downward aortic flow and upward transmittal flow should be seen.

Question 110

IVRT: Ideally the end of systolic downward flow should show the line (click) that corresponds to ……………….

Answer 110

Ideally the end of systolic downward flow should show the line (click) that corresponds to aortic valve closure.

Question 111

IVRT: Upward mitral flow should have a clear starting point or can also have a click representing ………….

Answer 111

Upward mitral flow should have a clear starting point or can also have a click representing mitral valve opening.

The time period between these 2 points represents IVRT

Question 112

Left auricular flow: Imaging plane used?

Answer 112

Left cranial transverse view of the left auricle or modified apical 4 ch view, which are twisted and tipped slightly until the auricle is seen are used to record left auricular filling and emptying.

Question 113

Where should the gate be placed for left auricular flow assessment?

Answer 113

Place PW gate at junction of the left auricular appendage and the and left atrium. Fig 3.63.

Question 114

Left auricular flow: The baseline is placed in the middle of the spectral image. Filling of the LA and auricle during ventricular systole is displayed …………… the baseline. Fig 3.64.

Answer 114

Filling of the LA and auricle during ventricular systole is displayed above the baseline. Fig 3.64.
An ECG helps identify this systolic flow. Negative flow is displayed during atrial emptying late in diastole.
Sometimes there are other pos and neg flows on this spectral image so an ECG identifies the correct flow profiles to use.