Ch 9 Apical Measurements Flashcards
What is the preferred method for 2D volume calculations, particularly LV EF + LA volume?
Biplane method of discs (modified simpson’s rule)
What is the biplane method of discs (modified simpson’s rule)?
Calculates ventricular volumes as a sum of a series of parallel slices (called discs) from the apex to base
List 2 advantages of using Simpson’s biplane method?
-2 planes of measurements give fewer assumptions about ventricular shape
-Changes in ventricular geometry caused by pathology won’t effect our accurate measurement of EF
(pathology such as Ao stenosis, volume overload + wall motion abnormalities due to MI or CAD)
Which views do we perform Simpson’s biplane measurements?
Zoomed up image of LV in AP4 + AP4
How do we get an EF by using Simpson’s biplane?
-By tracing the endocardial borders at end diastole + end systole
-Gives us an EF for AP4/AP2 + most importantly a biplane EF for both
List the 5 steps to perform a Simpson’s biplane measurement?
-Decrease depth + focus image on LV
-Place + set cursor on MV annulus
-Trace blood/tissue interface along endocardial border
-Place last cursor on lateral side of MV annulus
-Connect LV length line from MV annulus to apex of LV
Should AP4 + AP2 have very similar EFs?
Yes!
What is the normal range for end diastolic volume?
Women: 46-106 mL
Men: 62-150 mL
(males are larger b/c they have a bigger heart)
What is the normal range for end systolic volume?
Women: 14-42 mL
Men: 21-61 mL
What is the m/c used measurement for cardiac function?
LV EF
(EF = % of blood leaving heart during each contraction)
Formula for EF?
EF = (EDV - ESV) / EDV x 100
(this is the simplified version we use, the Simpson’s version is very complex)
Normal EF range?
Women: 54-74%
Men: 52-72%
How do we acquire a LA volume measurement?
-Measured at end systole in zoomed in AP4 + AP2
-Trace blood/tissue interface (endocardium) of LA
-Set first caliper under MV annulus, trace internal perimeter of LA + set second caliper under opposing annular side
-Adjust length line to be perpendicular to MV annulus, along length of LA
Upper normal limit for LA volume is what in men/women?
Men/women: 34 mL/m^2
List the ranges for a midly enlarged, moderately enlarged + severly enlarged LA volume in men/women?
Mild: 35-41 mL/m^2
Moderate: 42-48 mL/m^2
Severe: > 48 mL/m^2
Is LA volume indexed to BSA or gender?
BSA
What are some pathologies that could cause left atrial enlargement?
MV regurgitation
List 4 ways we can optimize our 2D image for best endocardial definition when we are going to do a Simpson’s biplane measurement?
-Gains
-Color maps/chroma maps
-Harmonics
-Dynamic range
Should pap muscles + trabeculations be ignored or included when doing a Simpson’s biplane measurement?
Ignored! Similar to how they are ignored in 2D linear measurements
(trace past the pap muscles b/c they are not the true LV wall + only exist in one plane)
How can we avoid LV shortening?
Drop down rib space or go more lateral if we are shortening the LV
Do diastole + systole measurements in AP4 + AP2 need to be performed in the same beat?
Yes!
LV length is perpendicular to what when doing a Simpson’s biplane measurement?
Base width - measured from center of MV annulus to LV apex
The length line variability b/w AP4 + AP2 should be what when doing a Simpson’s biplane?
<10%
Should the apex move much b/w diastole + systole when doing Simpson’s biplane measurements?
No!
EF variability b/w AP4 + AP2 should be within how many percentage points of each other when doing Simpson’s biplane measurements?
Within a few percentage points, unless WMAs are present
Are we allowed to “fudge” data when doing a Simpson’s biplane measurement?
NO, must get the entire LV in the sector and do it correctly. These are some of the most important images we take during an echo.
If we are foreshortening the LA, similar to the LV, how can we fix this?
-Drop down a rib space
-Angle slightly superior/inferior to ensure largest volume is assessed
The LA length is perpendicular to what structure when taking a left atrial volume measurement?
Perpendicular to the MV annular plane
Variability b/w AP4 + AP2 for left atrial volume measurements is what?
<5mm
LA length is measured from what 2 points when taking a LA volume measurement?
-From mid point of MV annulus
-To mid point of superior wall
Should we include the LA appendage or PVs in our LA volume measurement?
NO!
What happens if the LA length is not measured perpendicular to the MV annular plane when taking a LA volume measurement?
It creates a region of dead space, underestimating the true LA volume
What happens if the LA is foreshortened + the LA length is not perpendicular to MV annular plane when taking a LA volume?
It creates 2 areas of dead space that is not calculated in the LA volume, therefore underestimating the true LA volume
What happens if we include a PV into our LA volume?
We will overestimate the size of the LA
When are the RA linear measurements done? What view are they done in?
-End systole
-AP4
(think any measurements of the atria are always done in systole)
How do we take an RA major dimension?
Measure length of atria from superior to inferior
How do we take an RA minor dimension?
Measure width from lateral RA wall to IAS at the mid atrial level (defined by half of the RA long axis/length)
What is the normal RA major dimension range?
Less than 5.3 cm
What is the normal RA minor dimension range?
Less than 4.4 cm
How to do an RA volume tracing?
-Perform in AP4
-Trace blood/tissue interface (endocardium)
-Start under TV annulus
-RA length done at center of area under the TV annulus to the superior RA wall
-RA length is perpendicular to TV annular plane
(currently the ASE recommended way to quantify RA volume)
Why is the RA volume not a biplane measurement?
B/c we don’t have a verified second plane for the RA
(is technically more of an area than a volume)
What is the RA volume abnormal cut off in men + women?
Women: > 33 mL/m^2
Men: >39 mL/m^2
If we can not visualize a structure that well, should we still measure it to get some data?
No, no data is better than wrong data
What does TAPSE stand for?
Tricuspid annular plane systolic excursion
What does TAPSE assess?
Quantification of RV systolic function
(it is used in tandem with other measurements to create a complete clinical picture)
In which view is TAPSE typically performed in?
AP4 usually, can be done in MOD AP4 depending on visibility + angulation to m-mode cursor
Where is the m-mode cursor placed when doing TAPSE?
-Placed through the anterior TV annulus
-In line with the plane in which the annulus will move most PERPENDICULAR to the cursor throughout the cardiac cycle
Which part of the TAPSE tracing is measured?
The brightest/most continuous line is measured
(via slope or inferior/superior length)
Which part of the cardiac cycle is the TAPSE measurement done in?
-From end diastole to end systole
-Begins at R wave on ECG
What is the TAPSE normal range?
> 1.7cm or 17mm
In which view is the RVD1 + RVD2 measurements taken in? What part of the cardiac cycle?
MOD AP4 at end diastole
Where is the RVD1/RVIDd measurement taken?
Basal 1/3 of the RV
(also called RV basal dimension)
Where is the RVD2 measurement taken?
Middle 1/3 of the RV, at the level of the pap muscles
(also called RV mid dimension)
Are the RVD1 + RVD2 measurements done inner to inner or outer to outer?
Inner to inner edge + parallel to TV annulus
Does the RV apex need to be seen when doing RVD1 + RVD2 measurements?
Yes
Do we do the RVD1 or RVD2 measurement in lab?
RVD1/RVIDd
What is the normal range for RV chamber size in RVD1?
2.5 - 4.1 cm
(RVD1 = RV basal diameter)
What is the normal range for RV chamber size in RVD2?
1.9 - 3.5 cm
(RVD2 = RV mid diameter)
What does “FAC” stand for?
Fractional area change
(think RV systolic function)
In which view is RV FAC obtained in?
MOD AP4 or AP4 view
What information does RV FAC provide to us?
Provides an estimate of global RV systolic function (RV EF adjacent)
In which part of the cardiac cycle is RV FAC done in?
Endocardial tracing measured at end diastole + end systole
How do we trace the RV FAC?
From TV annulus along the RV free wall to the apex + back to the annulus along the IVS
Is RV FAC or TAPSE a better assessment of RV global function?
FAC - provides greater detail
(TAPSE only measures RV function in a single dimension)
What is the equation for RV FAC?
RV FAC (%) = 100(EDA-ESA)/EDA
RV FAC reflects what 2 components of RV contraction?
Both longitudinal + radial components
Should we include or exclude the trabeculations in the RV during a RV FAC?
Include them in our measurement (ignore them)
What RV FAC % indicates RV systolic dysfunction?
RV FAC < 35%
Why is it not possible to volumetrically quantify the RV the same way as the LV?
B/c we do not have a verified second view/plane
