Ch 15 Abnormal Doppler Patterns Flashcards
What is physiologic regurgitation?
It is trivial regurg - meaning it is a normal amount we expect to see in a normal healthy adult
Define valvular regurg?
Flow moving backwards through a valve, instead of forwards
Define valvular stenosis?
Flow being restricted from moving freely forward through a valve
Define intracardiac shunts?
Abnormal connections b/w areas of the heart that should NOT have communication b/w them
What 5 factors is it important to look at in terms of inspecting spectral doppler flow patterns?
-Speed
-Timing
-Intensity
-Shape
-Direction of blood flow
Why is speed important to look at when inspecting spectral doppler flow patterns: list 2 reasons why the normal values for valves should be memorized?
-Allows for recognition of one waveform vs another
-Allows for recognition of accelerated velocities
What can help determine the level of severity of regurgitation or stenosis?
Velocities - helps differentiate b/w mild, moderate + severe
(ex RVOT is smaller waveform compared to LVOT)
Do we need to know what mild, moderate + severe regurg or stenosis looks like right now in class?
No, just know the difference b/w trivial + very severe forms
Why is timing important to look at when inspecting spectral doppler flow patterns?
B/c we must understand exactly when each type of flow occurs during the cardiac cycle in order to make them recognizable
AR + MS both occur during diastole or systole?
Diastole
Does AR + MS both occur above or below the baseline?
Above
What is isovolumic relaxation time (IVRT)?
Time interval b/w AoV closure + MV opening
What is isovolumic contraction time (IVCT)?
Time interval b/w MV closure + AoV opening
Why is intensity important to look at when inspecting spectral doppler flow patterns?
B/c the more filled in + complete a doppler waveform is (higher amplitude), the more intense the level of flow is
Do doppler envelopes indicate a higher or lower intensity?
Higher - they are brighter + have more filling which indicates a higher level of severity
The more RBCs that get pushed through a valve, the higher or lower the amplitude of the signal?
Higher
Why is shape important to look at when inspecting spectral doppler flow patterns? List 2 reasons.
-B/c the normal contour of doppler waveforms of valves should be memorized, so when they differ they can be recognized
-Also assists in recognizing what type of flow is being visualized
AS + MR both occur during diastole or systole?
Systole
Does AS + MR both occur above or below the baseline?
Below
What is the normal velocity for the Ao?
1 m/s
Are AS jets usually more round or pointy?
Pointy
Do AS jets usually extend into the IVRT?
No, unlike the MR jet
Why is direction important to look at when inspecting spectral doppler flow patterns?
B/c normal directions for valves should be memorized, so when abnormal flow is visualized it is recognized
What is valvular regurg/insufficiency caused by?
-Congenital or acquired abnormalities of the valve leaflets
-Valve is not able to coapt (close) properly
Give an example of how abnormalities of associated supporting structures can cause regurg of an otherwise normal valve?
Ex: An enlarged Ao can cause a wide annulus, which then pulls the AoV apart + causes it to not be able to close as well anymore, resulting in Ao regurg
Is regurg always detectable via stethoscope?
No, echo is needed to find the origin of the murmur
How many imaging planes are needed to assess severity of regurg + stenosis?
Multiple
(stenosis - especially in the face of eccentric jets)
Is off-axis imaging allowed when trying to get a regurg or stenotic jet parallel to the u/s beam?
Yes
Contour of spectral doppler in regurg reflects the pressure difference b/w what?
B/w 2 chambers over the regurgitant flow period
In the presence of significant regurg, will the stroke volume across the valve increase or decrease?
Increase
Forward stroke volume is a combo of what 2 things?
Normal SV + regurgitant volume
In the presence of significant regurg, reversal of flow in the valves corresponds to what?
Their “inlets” + may be visualize with CD and spectral doppler
Where flow goes, pressure _____?
Follows
Excess flow will lead to increased or decreased pressure?
Increased
Increased volume + pressure will lead to what over time?
Chamber dilation
Having extra inflow coming into the heart will cause an increased preload or afterload?
Preload - b/c creates a higher volume in the LV
Before applying CD + spectral doppler, can we already become suspicious for the presence of regurg or stenosis?
Yes! M-mode + 2D imaging can give us signs before we turn on doppler to confirm regurg
Give an example of a structural abnormality that can be seen on an m-mode tracing that would make us suspicious of regurg?
Ex: AMVL fluttering due to AR
(image in slide shows the coaptation lines far apart in systole, when normally they should be closed with no gap present)
List 3 signs in 2D imaging that would make us suspicious of regurg?
-Chamber dilation (backflow of blood causes enlargement)
-Calcific changes (valves that can’t open properly m/c can’t close properly either)
-Prolapse (valve bowing/bending backwards causing leaks in valve)
What is valve prolapse?
A valve that bends further backward than it should, due to anomalous anatomical issues + allows for leaks
What 2 things are necessary to confirm the presence of valvular regurg?
-Spectral (CW) doppler
-CD
What should we automatically think about when we see chamber dilation + crunchy hyperechoic valves?
Dilation = regurg
Crunchy Valves = regurg + stenosis
MV prolapse is m/c in males or females?
Females
Is a small degree of regurg normal + common?
Yes - no adverse clinical outcomes will occur
List 3 ways we can tell if regurg is only a trace amount (physiologic/trivial)?
-Restricted to the area immediately adjacent to the valve closure
-Short in duration
-Incomplete spectral envelope
What is the least common type of regurg to see in a normal patient?
AR
Does severe AR, MR + TR have waveforms that look more round or pointy?
Pointy
Does MV stenosis, AoV stenosis + PV regurg all have waveforms that look the same or different?
Same
What 3 things is valvular stenosis caused by?
-Congenital or acquired abnormalities of the valve leaflets
-Post inflammatory processes (rheumatic fever)
-Age related calcification
(causing valve to be unable to open completely)
What 2 things will be visible on spectral doppler if stenosis is present?
-Higher than normal velocities
-Larger pressure gradients
Will areas immediately before or after a stenotic valve be dilated?
After (following the valve)
Is preload or afterload increased with stenosis?
Afterload
What classic shape does a bicuspid AoV have?
Football shape
Another name for rheumatic fever?
Scarlet fever
What is m/c associated with rheumatic fever?
MV stenosis
(can affect any valve, but m/c MV)
Give an example of a structural abnormality that can be seen on an m-mode tracing that would make us suspicious of stenosis?
Ex: Lack of E/A peaks on MV tracing
(severe tracings would show no E/A wave)
List 4 signs in 2D imaging that would make us suspicious of stenosis?
-Hyperechoic or echogenic thick valve (calcific changes)
-Reduced excursion of valve
-Ventricular hypertrophy
-Possibly atrial dilation
List 2 things we would expect to see when we use spectral (CW) doppler + CD to confirm presence of stenosis?
-Expect turbulent flow
-Expect regurg (b/c valves that can’t open properly also can’t close properly)
What classic shape is the AMVL when rheumatic fever is present?
Hockey stick shaped (MV stenosis)
AoV + PV stenosis waveforms look similar along with TV + MV stenosis waveforms, what is the only difference?
Velocities - AoV + MV will have higher velocity waveforms
What is the small hyperechoic area in a AS waveform?
LVOT
Does PV stenosis have waveforms that look more round or pointy with higher velocities?
Round
Semilunar regurg looks somewhat like what?
Atrioventricular stenosis
(know cardiac timing by ECG to keep things clear)
Atrioventricular regurg looks somewhat like what?
Semilunar stenosis
(know cardiac timing by ECG to keep things clear)
Volumetric flow rate must be constant at all 3 locations of a stenosis, what are they?
-Proximal to stenosis
-At stenosis
-Distal to stenosis
(continuity rule)
Is blood created or destroyed as it flows through a vessel?
Neither!
(continuity rule)
Average flow speed at a stenosis must be greater or weaker than the prox + distal part of the stenosis?
Greater - so that the volumetric flow rate can remain constant through all parts of the vessel
(continuity rule)
What principle says “what goes in, must come out”
Continuity principle
The continuity equation can calculate what?
Valve areas of any annulus, but m/c used for AoV
List what the variables mean in the continuity equation: A2 = A1 x V1 / V2
A2: AVA (aortic valve area)
A1: LVOT diameter
V1: LVOT VTI (time velocity interval)
V2: Peak AoV VTI
(all obtained from PLAX)
Explain the bernoulli effect?
-Drop in pressure at a stenosis due to high velocities
-The pressure difference allows for fluid to accelerate into the stenosis + decelerate out to maintain energy balance
As flow energy increases, pressure energy ____?
Decreases
(bernoulli effect)
Pressure energy is converted into ____ energy?
Flow energy - upon entry of stenosis then convert’s back exiting stenosis
(bernoulli effect)
What type of doppler is used to calculate pressure gradients b/w chambers?
Spectral doppler - allows quantification of the pressure gradient for areas of narrowing, such as a calcific AoV
(bernoulli effect)
List what the variables mean in the simplified bernoulli equation: P = 4v^2
P = pressure gradient
V = velocity
Solving for the bernoulli equation gives us what?
The pressure difference b/w 2 chambers at a specific point in time
List 3 things that we estimate the max + mean pressure gradients for?
-Aortic + pulmonic stenosis
-LVOT obstruction
-Right ventricular systolic pressure (RVSP)
(these are bernoulli equation applications)
List the formula for RVSP?
RVSP = 4 (tricuspid regurgitant velocity)^2 + RA pressure
(P = 4V^2 + RAP)
RVSP is a routine measurement taken in the echo lab to calculate what?
Right sided pressures
RVSP is used clinically to determine what?
If there is pulmonary hypertension
(a common response to many chronic left sided cardiac diseases)
RAP is assigned based on the visualized level of what?
Level of collapse of the IVC + its widest diameter
“V” in the bernoulli equation is generated by what?
By the Vmax of TR peak velocity from CW doppler
If there are 2 jets (stenosis or regurg) present, does the severity automatically go up now?
Yes, severity goes up a tick b/c there are 2 jets. Must doppler both jets independently
(ex: trivial now becomes mild)
