User guide

78 Measurement publications and terminology
Delta Pressure: Delta Time (dP:dT) in
mmHg/s
Otto, C.M. Textbook of Clinical Echocardiography .
2nd ed., W.B. Saunders Company, (2000), 117,
118.
32 mmHg/time interval in seconds
E:A Ratio in cm/sec
E:A = velocity E/velocity A
E/Ea Ratio
Reynolds, Terry. The Echocardiographer’s Pocket
Reference
. 2nd ed., School of Cardiac Ultrasound,
Arizona Heart Institute, (2000), 225.
E Velocity/Ea velocity
where: E velocity = Mitral Valve E velocity
Ea = annular E velocity, also
known as: E prime
Effective Regurgitant Orifice (ERO) in
mm
2
Reynolds, Terry. The Echocardiographer’s Pocket
Reference
. 2nd ed., School of Cardiac Ultrasound,
Arizona Heart Institute, (2000), 455.
ERO = 6.28 (r
2
) * Va/MR Vel
where: r = radius
Va = aliasing velocity
Ejection Fraction (EF), percent
Oh, J.K., J.B. Seward, A.J. Tajik. The Echo Manual .
2nd ed., Lippincott, Williams, and Wilkins, (1999),
40.
EF = ((LVEDV – LVESV)/LVEDV) * 100%
where: EF = Ejection Fraction
LVEDV = Left Ventricular End
Diastolic Volume
LVESV = Left Ventricular End
Systolic Volume
Elapsed Time (ET) in msec
ET = time between velocity cursors in milliseconds
Heart Rate (HR) in bpm
HR = 3 digit value input by user or measured on
M Mode and Doppler image in one heart cycle
Interventricular Septum (IVS) Fractional
Thickening, percent
Laurenceau, J. L., M.C. Malergue. The Essentials of
Echocardiography
. Le Hague: Martinus Nijhoff,
(1981), 71.
IVSFT = ((IVSS – IVSD)/IVSD) * 100%
where: IVSS = Interventricular Septal
Thickness at Systole
IVSD = Interventricular Septal
Thickness at Diastole
Isovolumic Relaxation Time (IVRT) in msec
Reynolds, Terry. The Echocardiographer’s Pocket
Reference
. School of Cardiac Ultrasound, Arizona
Heart Institute, (1993), 146.
|time a - time b|
Left Atrium/Aorta (LA/Ao)
Feigenbaum, H. Echocardiography . Philadelphia:
Lea and Febiger, (1994), 206, Figure 4-49.
Left Ventricular End Volumes (Teichholz)
in ml
Teichholz, L.E., T. Kreulen, M.V. Herman, et. al.
“Problems in echocardiographic volume
determinations: echocardiographic-angiographic
correlations in the presence or absence of
asynergy.”
American Journal of Cardiology ,
(1976), 37:7.
LVESV = (7.0 * LVDS
3
)/(2.4 + LVDS)
where: LVESV = Left Ventricular End
Systolic Volume
LVDS = Left Ventricular Dimension
at Systole