Arterial Hemodynamis Class 8 Unit 16 COPY

Question 1

Systolic velocity is ________ than diastolic velocity

Answer 1

Higher

Question 2

Why is systolic velocity higher than diastolic velocity?

Answer 2

Because of the heart pumping in systole and flowing moving on it’s own momentum in diastole .

Question 3

Does systolic velocity increase or decrease, as the blood flows to the ankles?

Answer 3

It decreases.

Question 4

When viewing in ultrasound of the peripheral arterial flow, what characteristic is usually found within the waveform?

Answer 4

Peripheral arterial flow is pulsatile, due to the pumping of the heart.

Question 5

Doppler velocity waveforms demonstrate what?

Answer 5

Demonstrate velocity changes, throughout the cardiac cycle

Question 6

In the peripheral arteries (le and ue), how is the velocity pattern demonstrated on doppler?

Answer 6

Velocity pattern is forward in systole, with a sharp upstroke, and narrow peak, followed by a short reversal of flow.

(Looks more triaphasic )

Question 7

In the normal le and ue, flow reversal is primarily due to what?

Answer 7

The resistance of the distal vascular bed that the artery is feeding.

Question 8

In normal le and ue arteries, what is the resistance controlled by?

Answer 8

Arterioles

Question 9

During exercise, what happens to the arterioles?

Answer 9

Arterioles open, which causes the resistance to decrease, and increases the flow needed for the muscles to work.

Question 10

What determines the diastolic portion of the velocity waveform?

Answer 10

Resistance of distal vascular bed

Question 11

Is there a high or low resistance, in the vessels feeding the brain, kidney, and liver?

Answer 11

Low resistance

Question 12

Peripheral arteries normally _________ resistance at rest.

Answer 12

High

Question 13

Why do arterioles open?

Answer 13

to reduce resistance and increase flow as needed.

Question 14

When do arterioles open?

Answer 14

• During a proximal obstruction in the artery.
• inflammation
• exercise
• anything that may cause decreased peripheral resistance.

Question 15

Normal mean velocities in the peripheral arteries

These are not criteria, just average velocities

Answer 15

Come back to this and put the chart

Question 16

When do velocities usually change in the peripheral arteries?

Answer 16

Usually around the stenosis and occlusion

Question 17

What does peri-stenosis mean?

Answer 17

Around the stenosis

Question 18

During peri-stenotic flow changes, as velocity increases, pressure ____________ .

Answer 18

decreases

Question 19

During peri-stenotic flow changes, as velocity decrease distally, pressure _________.

Answer 19

increases

Question 20

In a peri- stenotic, when the velocity decreases , and pressure increases, is the pressure higher than the inflow (initial) pressure?

Answer 20

no, its not as high as the inflow pressure.

Question 21

arterial velocity changes & waveforms

Answer 21

come back to put the image

Question 22

what has to happen to the velocity in a artery, in order to say there is a stenosis in it?

Answer 22

velocity increases at least double the pre-stenosis.

Question 23

Is pre stenosis predictable?

Answer 23

no

Question 24

In pre stenosis, if there is a triphasic waveform on Doppler, what may this indicate?

Answer 24

minor stenosis, or good collateralss

Question 25

During pre stenosis, does the Doppler signal have diastolic flow?

Answer 25

no

Question 26

During pre stenosis, a biphasic or monophasic doppler signal indicates ____________.

Answer 26

proximal disease present

Question 27

When you turn on Doppler in the stenosis, how will the waveform look?

Answer 27

it will have a spectral broadening | put in image 11

Question 28

During post -stenosis, what happens to the velocities?

Answer 28

they decrease along the artery distal to the stenosis

Question 29

During post-stenosis, what is present on the doppler waveform?

Answer 29

- initially turbulence is present - may have reversed flow under the peak - feathered peak velocities in the peak (put image 12)

Question 30

how will you know if the stenosis is significant, when viewing the waveform on doppler?

Answer 30

when moving distal from the pre stenosis, if it shows biphasic or monophasic waveform, you know its a significant.

Question 31

List characteristics that a PRE -occlusive doppler waveform may have in ultrasound

Answer 31

- may have no diastolic flow - may have diastolic flow if good collaterals exist to the sample volume - velocity may be low

Question 32

List characteristics that IN - occlusion doppler waveform may have in ultrasound

Answer 32

- no doppler signal | - b- mode usually shows echoes

Question 33

List characteristics that POST occlusion doppler may have in ultrasound

Answer 33

- almost always has a monophasic shape | - low velocity

Question 34

In systole, the systolic portion of the wave indicates what?

Answer 34

indicates the inflow patency or obstruction

Question 35

what does a slow upstroke indicates in systole?

Answer 35

a significant proximal obstruction

Question 36

In diastole, the diastolic portion of the wave indicates what?

Answer 36

the resistance of the distal vascular bed

Question 37

what does a high resistance wave demonstrate?

Answer 37

the diastolic flow, which can be at the baseline or below the baseline

Question 38

what does a low resistance wave demonstrate?

Answer 38

- forward flow throughout the cycle, about the baseline | - indicates proximal obstruction or post exercise or meds

Question 39

which arteries are normally high resistance?

Answer 39

- le arteries - ue arteries - eca - sma

Question 40

which arteries are normally low resistance?

Answer 40

- ica - vert - celiac - renal

Question 41

What are some normal situations that change the resistance of the arterioles?

Answer 41

-exercise (changes arteries from high resistance to low resistance, so flow can increase and help muscles work) - eating ( changes the superior mesenteric artery from normally high resistance to low resistance to help digestion) - post ichemia (normal high resistance to low resistance ) we see this when you come in from cold and fingers, toes and cheeks, may be low resistance to encourage flow

Question 42

Peripheral arteries distal to a significant obstruction will become low resistance, due to what?

Answer 42

arterioles opening to encourage flow

Question 43

The CCA will change from low to high resistance, proximal to an _________ occlusion, due to distal resistance,

Answer 43

ICA

Question 44

ICA will change from a low to high resistance proximal to an intracranial ________ occlusion, due to distal resistance.

Answer 44

ICA

Question 45

terminology : waveform patterns

Answer 45

slide 20 post

Question 46

terminology:waveform patterns

Answer 46

slide 21 post

Question 47

The systolic portion of the arterial waveform is affected by what?

Answer 47

A proximal obstruction, which may cause it to have a slow upstroke.

Question 48

The diastolic portion of the arterial waveform, demonstrates what?

Answer 48

the distal resistance.

Question 49

What is a characteristic of a high resistance waveform?

Answer 49

have diastolic flow at or below the baseline

Question 50

What is a characteristic of a low resistance waveform?

Answer 50

have forward flow throughout the cardiac cycle

Question 51

Do velocities increase or decrease, from the aorta to the ankles ?

Answer 51

They decrease

Question 52

what type of a waveform should you see with a normal le doppler signal ?

Answer 52

triphasic signal

Question 53

The normal triaphasic signals can become biphasic or monophasic under what conditions?

Answer 53

- excercise - inflammation - proximal significant obstruction - close proximity occlusion.

Question 54

in stenos the velocity is at least ________ the pre stenosis velocity.

Answer 54

2 times

Question 55

what is the flow pattern for post stenotic ?

Answer 55

turbulence, and further downstream a change in the waveform shape

Question 56

what are some recognizable flow patterns in the waveforms?

Answer 56

- triphasic - biphasic - monophasic - stenotic - turbulent - staccato - pendulum - bruit