Normal Chamber Quantitation Values
Ranges for normal dimensions of common structures are delineated in the table below. Note that though M-mode has long been used for measurement of LV dimensions, 2-D measurements are likely more reliable and are being used with increasing frequency as the standard measurements at many institutions. Further down the page we describe how to make these measurements.
PLAX Linear Measurements
Several parasternal linear measurements are made in end diastole to assess wall thickness and dimensions. One should avoid the papillary muscle and the RV portion of the septum if visiible.
The internal dimension in systole can be used to calculate fractional shortening, which here is 31%.
Both systolic and diastolic measurements can also be made using M Mode with care to align the cursor properly so it is perpendicular to the LV walls. Convention here is to measure leading edge to leading edge.
Ejection Fraction
4 Chamber Diastole
To calculate EF you will need to trace the LV in diastole and systole in both the 4 chamber and 2 chamber views making sure not to include papillary muscles or trabeculations.
From there the biplane method of disks is used to create volumes and determine the EF.
4 Chamber Systole
2 Chamber DIastole
EF is calculated as
(Diastolic Volume-Systolic Volume)/Diastolic Volume x 100%
Here it is 65%
2 Chamber Systole
LV Mass
Parasternal Short Axis - Mid LV
For LV mass you need to also trace the parasternal short axis
endocardial and epicardial borders. Try to avoid the papillary muscles and trabeculations.
LA Volume
4 Chamber Systole
For the LA volume you trace the LA in both the 4 and 2 chambers in ventricular systole. Be careful not to include the pulmonary veins which is a common error.
2 Chamber Systole
LA volume is calculated by taking both the area in the 4 chamber and 2 chamber view, multiplying them and then by 0.85 and dividing by the maximal length from each view (back wall to MV tips)
