Terason t3000 - Formulas Used in Echocardiography Measurements

Chapter 7 - Working With Measurements Measuring Cardiac Exams
Terason t3000 / Echo Ultrasound System User Guide 191
Formulas Used in Echocardiography Measurements
Formulas Used for Measurements in the 2D Window
2D Formulas
Name Variables Formula Units
LV Volume:
Method of
Disks, Biplane
a
di
: i
th
disk diameter of LV
apical 2-chamber (cm)
b
di
: i
th
disk diameter of LV
apical 4-chamber (cm)
L: chamber length from the
longer of A4c or A2c (cm)
20: number of disk segments
in ventricle
ml
LV Volume:
Method of
Disks, Single
Plane
a
di
: i
th
disk diameter of LV
apical 2- or 4-chamber
(cm)
L: chamber length of cavity
ml
Ejection
Fraction
Vs: LV volume systolic (ml)
Vd: LV volume diastolic (ml)
%
Stroke Volume V: LV volume (ml)
s: systole
d: diastole
ml
Cardiac Output SV: stroke volume (ml)
HR: heart rate (bpm)
l/min
Cardiac Index CO: Cardiac Output
BSA: body surface area (m
2
)
l/min/m
2
LV Mass A
1
: SAX epicardial diastolic
area (cm
2
)
A
2
: SAX endocardial diastolic
area (cm
2
)
L: apical length in diastole (cm)
t: mean myocardial thickness
g
cm
LV Mass Index LV: (g)
BSA: body surface area
m
2
Body Surface
Area
W: weight (range: 0.5–160 kg)
H: height (range: 150–204 cm)
m
2
Fractional Area
Change%
LVd: LV diastolic area (cm
2
)
LVs: LV systolic area (cm
2
)
%
Flow Area d: diameter (cm)
cm
2
V

4
---
20
i 1=

a
di
b
di
L
20
------
=
V

4
---
20
i 1=

a
2
di
L
20
------
=
EF
Vd Vs–
Vd
---------------------


100=
SV Vd Vs–=
CO
SV HR
1000
----------------------------=
CI
CO
BSA
------------=
LVMass 1.05
5
6
---
A
1
Lt+
5
6
---
A
2
L–


=
t
A
1

------


A
2

------


–


=
LVMI
LVMass
BSA
-----------------------=
BSA 0.007184 W
kg
0.425
H
cm
0.725
=
%FAC
LVd LVs–
LVd
----------------------------


100=
FlowArea 
d
2
4
-----


=