Aortic Valve Disease Exam #2 Flashcards
2D and M-mode measurements are good for assessing what in regards to AS?
assessing its PRESENCE
NOT
its severity (it is unreliable for severity)
m-mode from SAX to assess AS can be unreliable. True or False do you need to see all 3 cusps or is just 2 ok
ALL 3!
also can’t be any wall motion or septal wall abnormalities
lastly, decreased SV can affect cusp separation
TTE Planimetry is unreliable to assess AS as well. Many factors can affect your assessment such as (3)
- not imaging at max stenosis
- not being parallel
- heavy calcification, acoustic shadowing, and reverb artifact may obscure cusps
this measurement can ONLY be obtained in cath lab
peak to peak av gradient (LV peak pressure and peak aortic pressure)
this measurement is usually lower (by as much as ________mmHg) than the peak instantaneous gradient. *hint its the only measurement that can only be obtained in cath lab
30 mmHg!
peak to peak av gradient
4xV2squared solves for what
it is the SIMPLIFIED Bernoulli equation used to calculate PEAK INSTANTANEOUS GRADIENT
*use only if LVOT or V1 value is LESS THAN 1.5 m/sec
If the LVOT velocity is greater than OR EQUAL TO 1.5 m/sec, use this equation to solve for PEAK INSTANTANEOUS AV GRADIENT
4x (V2 squared - V1 squared)
What pressure constitutes SEVERE AS (give peak gradient value and mean gradient value)
peak value is 80mmHg
mean value is 50mmHg
Peak gradient and peak instantaneous gradient are the same thing TRUE OR FALSE
TRUE
measures stroke distance
velocity time integral
stoke distance is what exactly?
it is the distance that the column of blood travels past the LVOT or AoV during one cardiac cycle
why is the continuity equation used? for what type of patients?
it is used to calculate AVA or aortic valve area. It is used to calculate AVA instead of peak and mean gradient IN PATIENTS WITH LOW CARDIAC OUTPUT!!!!
mean and peak gradient are not reliable in low cardiac patients
What could cause a low pressure gradient even if a patient had severe AS
significant MR could cause AoV peak velocity to be underestimated (one of many things)
With these conditions AI, Anemia, Pregnancy… they could do what and cause an error in what
cause an err0r in PG calculation (INCREASE FLOW RATES) across the aorta
continuity equation is effective in calculating what in patients with what? *providing there is no what?
calculating effective valve area in low cardiac output state
*providing NO VSD is present!!!
when you are measuring LVOT diameter, make sure you are parallel to what
parallel to AORTIC VALVE PLANE
when do you measure the LVOT diameter (what point during cardiac cycle)
MID-SYSTOLE
window to view the LVOT should be from where. there are 2
apical 5 chamber view and apical long view
what’s the advantage of a non imaging probe
higher sensitivity and better access between rib spaces
3 Doppler abnormalities that all occur in ______ that make timing and waveform key to identify when using a non imaging probe
aortic stenosis
mitral regurgitation
tricuspid regurgitation
jets mistaken for AS
sub aortic obstruction
mitral regurgitation
tricuspid regurgitation
ventricular septal defect
pulmonic artery stenosis
peripheral vascular stenosis
An MR jet is _______in comparison to an AS jet
peak velocity is higher (longer duration)
MR usually GREATER than 4 to 5 m/s
the velocity of tricuspid regurgitation usually displays
RESPIRATORY VARIATION
Situation: you’re having trouble measuring an LVOT diameter… this is impeding you from obtaining an accurate continuity equation…. what measurement should you use now?
DI or dimensionless index
AKA
VELOCITY RATIO
It is INDEPENDENT of CO (measurement)
DI
Dimensionless Index
aka
Velocity Ratio
DI =
VTILVOT / VTIA
AoV index =
AVA/BSA